- Email: [email protected]
Elevated CO2 affects anxiety but not a range of other behaviours in juvenile yellowtail kingfish
Journal Pre-proof Elevated CO2 affects anxiety but not a range of other behaviours in juvenile yellowtail kingfish Michael D. Jarrold, Megan J. Welch, Shannon J. McMahon, Tristan McArley, Bridie J.M. Allan, Sue-Ann Watson, Darren M. Parsons, Stephen M.J. Pether, Stephen Pope, Simon Nicol, Neville Smith, Neill Herbert, Philip L. Munday PII:
S0141-1136(19)30501-X
DOI:
https://doi.org/10.1016/j.marenvres.2019.104863
Reference:
MERE 104863
To appear in:
Marine Environmental Research
Received Date: 7 August 2019 Revised Date:
12 December 2019
Accepted Date: 14 December 2019
Please cite this article as: Jarrold, M.D., Welch, M.J., McMahon, S.J., McArley, T., Allan, B.J.M., Watson, S.-A., Parsons, D.M., Pether, S.M.J., Pope, S., Nicol, S., Smith, N., Herbert, N., Munday, P.L., Elevated CO2 affects anxiety but not a range of other behaviours in juvenile yellowtail kingfish, Marine Environmental Research (2020), doi: https://doi.org/10.1016/j.marenvres.2019.104863. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2019 Published by Elsevier Ltd.
Michael Jarrold: formal analysis, data curation, writing – original draft, Megan Welch: investigation, writing – review and editing, Shannon McMahon: investigation, writing – review and editing, Tristan McArley, investigation, data curation, formal analysis, writing – review and editing, Bridie Allan: investigation, writing – review and editing, Sue-Ann Watson: investigation, formal analysis, writing – review and editing, Darren M. Parsons: conceptualization, project administration, funding acquisition, writing – review and editing, Stephen Pether: methodology, investigation, project administration, writing – review and editing, Stephen Pope: methodology, investigation, writing – review and editing, Simon Nicol: conceptualization, funding acquisition, writing – review and editing, Neville Smith: conceptualization, funding acquisition, writing – review and editing, Neill Herbert: investigation, project administration, formal analysis, writing – review and editing Philip Munday: conceptualization, investigation, project administration, funding acquisition, supervision, writing – original draft
1
Elevated CO2 affects anxiety but not a range of other behaviours
2
in juvenile yellowtail kingfish
3 4 5
Running head: Elevated CO2 effects on kingfish behaviour
6 7
Michael D. Jarrold1, Megan J. Welch1, Shannon J. McMahon1, Tristan McArley2,
8
Bridie J.M. Allan1,3, Sue-Ann Watson1,4, Darren M. Parsons2,5, Stephen M.J. Pether6,
9
Stephen Pope5, Simon Nicol7, Neville Smith8, Neill Herbert2 & Philip L. Munday1*
10
1
11
University, Townsville, Queensland, 4811, Australia
12
2
13
3
Department of Marine Science, University of Otago, Dunedin 9016, New Zealand
14
4
Biodiversity and Geosciences Program, Museum of Tropical Queensland, Queensland
15
Museum, Townsville, Queensland, 4810, Australia
16
5
National Institute of Water and Atmospheric Research Ltd, Auckland, New Zealand
17
6
National Institute of Water and Atmospheric Research, Northland Marine Research Centre,
18
Station Road, Ruakaka 0116, New Zealand
19
7
Insitute for Applied Ecology, University of Canberra, ACT 2617, Australia
20
8
Oceanic Fisheries Programme, Pacific Community, CPS – B.P. D5 98848, Noumea, New
21
Caledonia
Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook
Leigh Marine Laboratory, The University of Auckland, Leigh 0985, New Zealand
22 23
*Corresponding author email: [email protected]
24 25 1
26
Abstract
27
Elevated seawater CO2 can cause a range of behavioural impairments in marine fishes.
28
However, most studies to date have been conducted on small benthic species and very little
29
is known about how higher oceanic CO2 levels could affect the behaviour of large pelagic
30
species. Here, we tested the effects of elevated CO2, and where possible the interacting
31
effects of high temperature, on a range of ecologically important behaviours (anxiety,
32
routine activity, behavioural lateralization and visual acuity) in juvenile yellowtail kingfish,
33
Seriola lalandi. Kingfish were reared from the egg stage to 25 days post-hatch in a full
34
factorial design of ambient and elevated CO2 (~500 and ~1000 μatm pCO2) and temperature
35
(21 °C and 25 °C). The effects of elevated CO2 were trait-specific with anxiety the only
36
behaviour significantly affected. Juvenile S. lalandi reared at elevated CO2 spent more time
37
in the dark zone during a standard black-white test, which is indicative of increased anxiety.
38
Exposure to high temperature had no significant effect on any of the behaviours tested.
39
Overall, our results suggest that juvenile S. lalandi are largely behaviourally tolerant to
40
future ocean acidification and warming. Given the ecological and economic importance of
41
large pelagic fish species more studies investigating the effect of future climate change are
42
urgently needed.
43 44
Keywords: anxiety, behavioural lateralization, vision, temperature, ocean acidification,
45
climate change, Seriola lalandi
2
46
Introduction
47
Rapidly increasing atmospheric carbon dioxide (CO2) levels are driving a reduction in
48
seawater pH, a process referred to as ‘ocean acidification’ (OA) (Doney et al., 2009; Orr et
49
al., 2005). Recently, atmospheric CO2 levels surpassed 415ppm for the first time in human
50
history (www.esrl.noaa.gov/gmd/ccgg/trends/), and based on the business-as-usual RCP8.5
51
emissions scenario could reach 1000 ppm by the end of the century (Meinshausen et al.,
52
2011). The partial pressure of CO2 (pCO2) at the ocean’s surface is in approximate gas
53
equilibrium with atmospheric CO2 and thus oceanic pCO2 is rising at the same rate as the
54
atmosphere (Doney et al., 2009). However, recent models suggest that seasonal pCO2 cycles
55
in oceans will increase in magnitude throughout the century due to the reduced buffering
56
capacity of acidified seawater (Gallego et al., 2018; Kwiatkowski and Orr, 2018; McNeil and
57
Sasse, 2016). Consequently, surface ocean pCO2 could exceed 1000 μatm for many months
58
each year well before the same average CO2 concentration occurs in the atmosphere
59
(Gallego et al., 2018; Kwiatkowski and Orr, 2018; McNeil and Sasse, 2016). The early life
60
stages of marine organisms are more susceptible to elevated CO2 than older age classes, at
61
least in part because of the relatively high energetic cost of regulating acid base balance
62
when body size is small (Brauner, 2009; Melzner et al., 2009). Indeed, many studies have
63
shown that exposure to elevated CO2 can negatively affect various traits in early life stages
64
across a range of marine taxa (Cattano et al., 2018; Przeslawski et al., 2015; Wittmann and
65
Pörtner, 2013).
66 67
One of the most unexpected impacts of exposure to elevated CO2 to be discovered in
68
marine organisms are effects on sensory systems and ecologically important behaviours
3
69
(Cattano et al., 2018; Clements and Hunt, 2015; Nagelkerken and Munday, 2016). Altered
70
behavioural responses at high CO2 have been observed in a variety of marine taxa, although
71
the majority of work has been conducted on small benthic fishes (Nagelkerken and Munday,
72
2016). For example, over 70 studies have shown that a range of behavioural responses, in
73
both tropical and temperate fish species, are altered under elevated CO2 levels, including
74
but not limited to: predator avoidance/prey detection behaviour, escape responses,
75
activity/anxiety levels, learning ability and lateralization (Cattano et al., 2018; Nagelkerken
76
and Munday, 2016). Behavioural impairments caused by exposure to elevated CO2 have
77
been linked to increased mortality of small juvenile fish in natural settings, inferring that
78
recruitment could be affected by projected future CO2 levels in the ocean (Chivers et al.,
79
2014; Munday et al., 2012, 2010). However, while behavioural impairments at elevated CO2
80
have been observed in a wide range of species, from coral reef fishes to salmon, it is also
81
apparent that not all behaviours are affected, there is interspecific variation in sensitivity,
82
and that some species are much less affected than others (Cattano et al., 2017; Ferrari et al.,
83
2011; Heinrich et al., 2016; Jarrold and Munday, 2018a; Jutfelt and Hedgärde, 2015;
84
Laubenstein et al., 2018; Schmidt et al., 2017; Sundin et al., 2017; Sundin and Jutfelt, 2015).
85 86
Large pelagic fishes perform fundamental ecological roles as the ocean’s top predators.
87
They influence the structure and functioning of marine ecosystems, exerting strong top-
88
down influences on marine food webs (Casini et al., 2009; Frank et al., 2005). Furthermore,
89
they are a critical food source for millions of people in coastal regions worldwide and
90
constitute a large proportion of wild-caught fisheries (FAO, 2016). Despite their high
91
ecological and economic importance, little is known about the potential impacts of ocean
92
acidification on populations of large pelagic fishes owing to the difficulties in rearing and 4
93
closing the life cycles of these species in captivity. It was initially suggested that pelagic fish
94
could be more susceptible to rising levels of ocean pCO2 owing to the relatively stable
95
environmental conditions they experience in open waters (Munday et al., 2008; Nilsson et
96
al., 2012), compared to fish from coastal waters which are subject to highly fluctuating
97
temperature and pH conditions (Hofmann et al., 2011). Nevertheless, the few studies that
98
have tested the effects of end of century projected pCO2 levels on the early life stages of
99
large pelagic fishes have found limited effects on survival, growth and swimming ability
100
(Bignami et al., 2014, 2013; Bromhead et al., 2015; Munday et al., 2016; Watson et al.,
101
2018). Whether or not elevated CO2 causes behavioural impairments in large pelagic fish is
102
largely unknown. To date, only a handful of studies have tested the effects of elevated CO2
103
on behavioural traits in large pelagic fish, with most testing swimming activity and reporting
104
minimal effects (Bignami et al., 2017, 2014; Laubenstein et al., 2018; Munday et al., 2016).
105 106
In addition to ocean acidification, higher concentrations of atmospheric CO2 cause more
107
heat to be retained within the atmosphere, most of which is absorbed by the oceans. For
108
ectothermic animals, such as fishes, temperature dictates metabolic performance and
109
bioenergetics (Enders and Boisclair, 2016; Killen et al., 2010; Sandersfeld et al., 2017). Thus,
110
changes in ambient temperature can affect behaviours, such as foraging and routine activity
111
levels, that are linked to bioenergetics (Allan et al., 2017; Jarrold and Munday, 2018a;
112
Nowicki et al., 2012; Scott et al., 2017; Watson et al., 2018). In some cases, elevated
113
temperature has been shown to have greater overall effects on behavioural responses
114
compared to elevated CO2, especially on behaviours linked to metabolic performance (Allan
115
et al., 2017; Jarrold and Munday, 2018a; Laubenstein et al., 2018; Sswat et al., 2018; Watson
116
et al., 2018). In other cases, significant synergistic and antagonistic interactions between 5
117
elevated CO2 and temperature have been observed (Domenici et al., 2014; Ferrari et al.,
118
2015; Pistevos et al., 2017). Collectively, these studies highlight the importance of studying
119
the combined effects of ocean acidification and ocean warming to accurately predict the
120
behavioural responses of marine fishes to future climate change and the associated
121
ecological consequences.
122 123
The aim of this study was to determine the effects of elevated CO2 and temperature on
124
behavioural responses during the early life history of a large pelagic fish species. To do this,
125
we used the yellowtail kingfish, Seriola lalandi, which has emerged as a potential model
126
species for testing the effects of environmental change on large pelagic fishes (Laubenstein
127
et al., 2018; Munday et al., 2016; Watson et al., 2018), because it is one of the few species
128
that can be reliably reared in captivity (Symonds et al., 2014). The effects of elevated CO2 on
129
behavioural responses of S. lalandi reported to date has been variable. Startle responses of
130
juvenile S. lalandi (18-22 days post hatch (dph)) were impaired by 985 μatm CO2 (Watson et
131
al., 2018), but there was no significant effect of elevated CO2 on activity, startle response
132
and phototaxis at 3 dph (Munday et al., 2016), suggesting that juveniles may be more
133
sensitive to elevated CO2 than very recently hatched larvae. Here, we tested the effects of
134
elevated CO2 on several previously untested behaviours (anxiety, behavioural lateralization
135
and visual acuity) in juvenile S. lalandi (18-25 dph). Preliminary testing using a two-channel
136
flume and a feeding trial found that juvenile kingfish did not respond to the chemical cues of
137
putative predators (juvenile hapuku, Polyprion oxygeneios, and larger juvenile kingfish),
138
therefore it was not possible to test if elevated CO2 affected olfactory response to predator
139
cues, as has been observed in some other fishes (e.g. Ou et al., 2015; Porteus et al., 2018;
140
Williams et al., 2019). Where possible, we also tested the interacting effects of elevated 6
141
temperature on the same behavioural traits. To achieve this, we reared juvenile S. lalandi at
142
current-day ambient CO2 levels (~500 μatm) and average summer temperature for the study
143
location (21°C), crossed with elevated CO2 (~1000 μatm) and temperature (25°C) based on
144
projections for the open ocean by the year 2100 under RCP 8.5 (Collins et al., 2013), and
145
tested behavioural responses using similar methods to previous studies.
146 147
Materials and Methods
148
Study location and species
149
This study focused on the New Zealand population of the yellowtail kingfish, Seriola lalandi,
150
and was conducted at the National Institute of Water and Atmospheric Research (NIWA)
151
Northland Marine Research Centre, Ruakaka, New Zealand. Seriola lalandi is a large coastal
152
pelagic fish with a circumglobal distribution in subtropical waters. In New Zealand waters it
153
reaches up to 1.7 m in length and over 50 kg in weight (McKenzie et al., 2014; Taylor and
154
Willis, 1998). It is a powerful swimmer adapted to a pelagic lifestyle and supports an
155
important recreational and commercial fishery in New Zealand, Australia, Japan and other
156
subtropical regions (McKenzie, 2014; Sicuro and Luzzana, 2016). Kingfish spawn pelagic eggs
157
that hatch within 2-3 days depending on temperature. Flexion in pelagic larvae occurs from
158
about 10 dph and they are metamorphosed juveniles around 20-23 dph (Symonds et al.,
159
2014; Watson et al., 2018). Juveniles have a pelagic lifestyle, often sheltering from large
160
predators under floating debris or weed (Roberts et al., 2015). Juveniles grow rapidly,
161
reaching approximately 0.5 m in length by one year of age in the wild (Stewart et al. 2004).
162 163
Broodstock, eggs and larval culture
7
164
Spawning stocks of S. lalandi were maintained outdoors in 20 m3 circular tanks. Each
165
broodstock tank contained between four and six locally sourced, wild-caught adult fish that
166
had been domesticated in tanks for up to 9 years (approximately equal sex ratio in each tank
167
as occurs in the wild (Poortenaar et al., 2001)). In the current study, experiments were
168
conducted in conjunction with a natural spawning event that occurred on the night of
169
23/01/2017 using eggs collected from four broodstock tanks. Parentage analysis showed
170
that a total of 5 adult females and 10 adult males contributed to the spawning (Munday et
171
al., 2019). Long-term mean summer temperatures for the region are 21°C (Shears and
172
Bowen, 2017), however, local ocean conditions vary naturally and ambient water
173
temperature was 19–20°C in the 5 days immediately prior to spawning and then dropped to
174
18.2°C on the night of spawning. Ambient seawater pHtotal and pCO2 were 7.91 and 589
175
µatm, respectively, in the broodstock tanks. Floating eggs from the four contributing tanks
176
were collected the morning after spawning, mixed, rinsed with oxygenated seawater for 5
177
min, and disinfected with Tosylchloramide (chloramine-T) at 50 ppm for 15 min. Eggs were
178
then rinsed with seawater and distributed into 24 conical 400 L incubation tanks at a density
179
of approximately 100,000 eggs per tank at 12:45h on 24/01/2017. The 400 L incubation
180
tanks were at the nominal CO2 levels and ambient ocean temperature (18.2 °C) at stocking.
181
Heating was turned on at 15:30 h and temperature was allowed to slowly rise to the
182
treatment set points of 21°C and 25°C overnight. Tanks received flow-through seawater at a
183
flow rate of 3 L min-1 with a photoperiod of 14 hours light and 10 hours dark. Eggs hatched
184
two days after stocking at 25°C and three days after stocking at 21°C and larvae were reared
185
for a further 1 day in the incubation tanks before transfer to grow-out tanks.
186
8
187
At 1 dph, larvae were transferred from their rearing tanks into 24 reciprocal grow-out tanks
188
at a density of approximately 45,000 larvae per tank (44,227 ± 2,152 mean ± SD). Grow-out
189
tanks were 1,500 L circular tanks with slightly sloping bottoms with a black internal surface.
190
Each grow-out tank received flow-through seawater at either 21 or 25°C with a photoperiod
191
of 14 hours light and 10 hours dark and at a flow rate of 3 L min-1 and gentle aeration. The
192
flow rates used here are within normal incubation and larvae rearing parameters (3-4 L min-
193
1
194
relatively low density in this trial (250 eggs L-1 c.f. 1,000 eggs L-1 for commercial production).
195
This flow rate also afforded greater margin for maintaining constant temperatures, while
196
providing gentle mixing of eggs and larvae. The overall hatch rates for this trial (76%) was
197
similar or better than those under normal operations (70% in 2019). Larvae were fed with
198
rotifers enriched with S.presso (INVE Aquaculture, Belgium) up to 4 times per day until 14
199
dph, transitioning to S.presso enriched Artemia up to 4 times per day from 11 dph until the
200
end of the experiment at 25dph. Tanks were siphoned daily to remove waste in order to
201
maintain good water quality. Each tank also had a surface skimmer to remove any excess
202
oils from enriched rotifers and Artemia. This study followed animal ethics guidelines at
203
James Cook University (JCU Animal Ethics number: A2357).
, 100-133 mins full turnover rate) for commercial production at NMRC, particularly for the
204 205
Experimental system and water chemistry
206
Seawater pumped from the ocean was filtered through mixed-media, bag filtered to 5 µm,
207
UV light treated to 150 mW.cm-2, heated to 21°C and delivered to large header tanks.
208
Oxygen diffusers in the header tanks maintained baseline minimum dissolved oxygen (100 %
209
saturation) and foam fractionators removed any additional organics. Seawater from each
210
header tank was gravity-fed into eight separate 100 L sump tanks where temperature was 9
211
maintained at ambient control 21°C or elevated to 25°C and CO2 was maintained at ambient
212
control (~500 µatm) or elevated (~1,000 µatm) CO2 in a fully-crossed 2 x 2 experimental
213
design with 2 replicate sumps for each treatment. Seawater from each of the eight
214
treatment sumps was pumped into three of the 400 L incubation tanks during the egg
215
incubation stage and three of the 1,500 L rearing tanks during the grow-out stage, so that
216
there were six replicate experimental tanks at each temperature and CO2 level throughout
217
the experiment.
218 219
Filtered seawater at ambient temperature was heated to 21°C by holding in a 4000L header
220
tank. This water was side streamed through a heat pump (Hot Water Heat Pumps
221
model 7GP35HC-3). This water was delivered to each sump, with each sump having a float
222
valve to maintain a full water level. Water for the 25°C treatment was heated further in the
223
sumps with electronic heaters (2 x Helios 2kW immersion heaters per sump) regulated by
224
Carel IR33 controllers (Carel Industries, Padova, Italy). Temperature was maintained within
225
±0.3°C of the setpoint in all treatments.
226 227
An aquarium pump (Hailea HX-6540) pumped water from each treatment sump to the
228
experimental rearing tanks containing kingfish eggs or larvae. A second aquarium pump
229
(AquaOne Maxi 103) in each sump ensured that the water was well mixed and served as the
230
dosing point for the elevated pCO2 treatments. Elevated pCO2 seawater was achieved by
231
dosing treatment sump tanks with CO2 to the desired pH set point using a pH computer
232
(Aqua Medic, Germany). CO2 was introduced to the pump inlet where it was immediately
233
dissolved by the impeller. A needle valve was used to regulate the flow of CO2 into the
234
powerhead to ensure a slow, steady stream of CO2 into the sump. This slow dosing and 10
235
rapid mixing in the treatment sump tanks ensured that each experimental rearing tank
236
received a steady supply of well-mixed water. All treatment sump tanks, and experimental
237
rearing tanks were housed in environmentally controlled rooms.
238 239
The pHtotal and temperature of each rearing tank were measured daily (SG8 SevenGo Pro,
240
Mettler Toledo, Switzerland). The pH electrode was calibrated with Tris buffers (Scripps
241
Institution of Oceanography, batch number 26). Water samples for total alkalinity (TA)
242
analysis were taken from all rearing tanks at 1, 11 and 21 dph. TA and salinity determination
243
was conducted by the University of Otago Research Centre for Oceanography, Dunedin,
244
New Zealand. Salinity was 35.6 (±0.01) during the experiment. Carbonate chemistry
245
parameters in each tank were calculated in CO2SYS using the measured values of pHtotal,
246
salinity, temperature and TA and the constants K1, K2 from Mehrbach et al. (Mehrbach et
247
al., 1973) refit by Dickson and Millero (Dickson and Millero, 1987), and Dickson et al.
248
(Dickson, 1990) for KHSO4. Seawater carbonate chemistry parameters are shown in Table 1.
249 250
Table 1. Experimental water chemistry. Mean (± S.D.) temperature, salinity, pHtotal, total
251
alkalinity and pCO2 in experiments with yellowtail kingfish (Seriola lalandi) eggs and larvae.
252
Temperature, salinity, pHtotal and total alkalinity were measured directly, pCO2 was
253
estimated from these parameters using CO2SYS. Raw data are available at the Tropical Data
254
Hub; http://doi.org/10.25903/5d54e90e5ce92.
255 Treatment
Treatment
Temperatu Salinity
CO2
temperature
re (°C)
Control
21 °C
21.1 (0.1)
pHtotal
Total alkalinity
pCO2 (µatm)
(µmol.kg-1 SW) 35.6
8.00
11
2318.8 (7.2)
462.0 (42.8)
Control
Elevated
Elevated
25 °C
21 °C
25 °C
24.8 (0.4)
21.1 (0.1)
24.9 (0.4)
(0.1)
(0.03)
35.6
7.94
(0.1)
(0.01)
35.6
7.72
(0.2)
(0.03)
35.6
7.70
(0.1)
(0.01)
2319.9 (7.7)
538.3 (15.6)
2319.0 (3.8)
959.8 (57.3)
2320.0 (6.2)
1010.6 (30.4)
256 257 258
Behavioural trials
259
Behaviours were tested in juvenile S. lalandi between 18-25 dph. The standard length of fish
260
tested ranged from 7.73 ± 1.20mm (mean ± SD) (21°C) to 11.15 ± 2.75mm (25°C) (there was
261
no effect of CO2 treatment on standard length (Watson et al., (2018)). Behavioural trials
262
were conducted at both ambient and elevated CO2 at 21°C and 25°C, except where specified
263
below where only one temperature treatment was tested for each CO2 level. The datasets
264
generated analysed during the current study are available from the corresponding author on
265
request or via the Tropical Research Data Hub (doi: 10.25903/5df17da5f534f).
266
Anxiety and activity trials
267
A light/dark preference (scototaxis) test was used to compare anxiety levels in juvenile S.
268
lalandi among treatments. The light/dark test is a standard method for measuring anxiety-
269
like behaviours in fish and has been validated by pharmacological studies (Maximino et al.,
270
2013, 2011; Mezzomo et al., 2016).In this test, an increase in dark compartment activity
271
(duration and/or entries) reflects increased anxiety, whereas an increase in white
272
compartment activity reflects reduced anxiety. Juvenile kingfish often shelter from large
12
273
predator under floating debris or weed (i.e. dark patches) and so this is an ecologically
274
relevant test for this species. The light/dark arena was a polyethylene tank (measuring 9.5
275
cm wide by 15.5 cm long and 7 cm deep), which had walls lined with black non-reflective
276
tape in one half and white non-reflective tape in the other half, split in the width of the
277
chamber. A barrier (24cm x 22cm x 25.5 cm (LxWxH)) was placed around the arena to
278
eliminate disturbance and to enable the camera (Cannon G15) to be dorsally positioned
279
above the chamber. At the start of each trail the chamber was filled to a depth of 1.5 cm
280
with 200 ml of water from the respective treatment water of the fish being tested, with
281
water being changed between trials. Fish were transferred into the chamber using a small
282
hand net to avoid food entering the testing arena. To standardise for location, fish were
283
placed in the centre of the arena in line with the dark/light divide to avoid an initial
284
preference for the light or dark zone. 72 fish were tested per treatment. Fish were filmed for
285
10.5 min. The first 2 minutes and last 30 seconds of each video were excluded to allow time
286
for the fish to adjust to the arena at the start of the trail and to allow recording error time in
287
manually stopping the camera. A 2 minute acclimation period is consistent with studies that
288
have validated the light/dark test for measuring anxiety in fish (Hamilton et al., 2014;
289
Maximino et al., 2013, 2011; Mezzomo et al., 2016). The amount of time spend in each zone
290
and routine activity in the arena were determined from the trimmed 8-minute video using
291
motion-tracking software (Lolitrack v4.1.0, Loligo Systems, Tjele, Denmark). Anxiety was
292
quantified as the percentage of time spent in the dark zone. We also quantified routine
293
activity as time active (%) and average swimming velocity (cm s-1). All videos were analysed
294
with the observer blind to treatment.
295 296 297 13
298
Behavioural lateralization
299
Lateralization in juvenile S. lalandi was determined using a detour test in a two-way T-maze
300
using methods similar to those described by Welch et al. (2014). The two-way T-maze
301
consisted of an experimental arena (60 x 30 x 20 cm, L x W x H), with a runway in the middle
302
(25 x 3 cm, L x W), and at both ends of the runway (3 cm ahead of the runway) an opaque
303
barrier (12 x 12 x 1 cm) was positioned perpendicular to the runway. The maze was filled to
304
a depth of 2 cm with respective treatment water of the fish being tested. To maintain
305
temperature and dissolved oxygen, the water was changed after each trial. A single fish was
306
placed at one end of the T-maze and given a 2 min habituation period, during which time it
307
could explore the apparatus. This amount of acclimation time is within the range normally
308
reported during lateralization trials, with many reporting significant effects (Hamilton et al.,
309
2017; Jarrold et al., 2017; Lopes et al., 2016; Näslund et al., 2015; Sundin and Jutfelt, 2015).
310
At the end of the habituation period the fish was gently guided into the runway using a flat,
311
black plastic board. This was repeated for a total of 10 runs. 50 fish per treatment were
312
tested. To account for any possible asymmetry in the maze, turns were recorded alternately
313
on the two ends of the runway. Turning preference (i.e. bias in left or right turns) at the
314
population level was assessed using the relative lateralization index (LR, from -100 to +100,
315
indicating complete preference for left and right turning, respectively) according to the
316
formula: LR = [(Turn to the right - Turn to the left) / (Turn to the right + Turn to the left)] *
317
100. The strength of lateralization (irrespective of its direction) was also assessed at the
318
individual-level using the absolute lateralization index LA (ranging from 0 (an individual that
319
turned in equal proportion to the right and to the left) to 100 (an individual that turned right
320
or left on all 10 trials)). Trials were filmed dorsally (Canon G15) and turning direction was
321
scored live with later video validation. The first direction turned when the fish exited the 14
322
runway was recorded. Lateralization trials were only conducted on fish reared at 25 °C as
323
those reared at 21°C were too small for the testing arena.
324 325 326 327 328
Vision
329
visually resolve fine scale detail on a moving background. Visual ability was measured via
330
the presence (or not) of an optomotor response to visual stimuli in a similar fashion to that
331
described by Herbert and Wells, (2002). The optomotor response is an innate behaviour
332
that enables sensory adept animals, including fish, to stabilise their view of and position in
333
the environment.
Changes in visual acuity were assessed by measuring the ability of juvenile S. lalandi to
334 335
The optomotor device consisted of a wooden cabinet with circular holes on the top that
336
provided the frame through which recording cameras and fish holding containers were
337
suspended. Individual juvenile S. lalandi were held in clear 50 mL plastic bottles, suspended
338
on monofilament fishing line 100 mm below a camera housed within a PVC pipe. This setup
339
allowed kingfish to be suspended within a striped rotating drum whilst the camera provided
340
a clear view of kingfish activity. The optomotor device comprised a circular drum (height =
341
215mm, diameter = 250mm) with a patterned paper strip of alternating black and white
342
vertical bars housed atop a motorised spinning plate. Motors were set to spin in a clockwise
343
direction, at a fixed rate of four revolutions min-1. The paper strips had a residual distance
344
(RD, linear distance from midpoint of the bottle to the patterned strips) of 105 mm and six
345
variants of the paper strips (with different bar widths) were used. The width of the black
346
and white bars was calculated to provide a subtended acuity angle of 2°, 3°, 4°, 6°, 8°, and
15
347
10°, assuming fish reacted to the stimulus across the residual distance. A white paper strip
348
with no black bars was used to provide a control condition (0° acuity angle).
349 350
Juvenile S. lalandi were transferred into test bottles containing water at the same CO2 and
351
temperature conditions as their source tank. Only fish reared at 21oC were tested as those
352
reared at 25oC were too fast for the apparatus. Fish were then exposed to all of the
353
patterned strips in turn by manually replacing the patterned strips between tests. At the
354
start of each test sequence, the camera and bottle on the PVC pipe were lowered into a
355
rotating optomotor device, and the fish was allowed to acclimate within stimulus-active
356
conditions for five minutes before data recording was initiated. Fish behaviour was digitally
357
recorded for three minutes, as well as observed in real-time. The behavioural response of
358
each fish was quantified using angular swimming velocity (net revolutions min-1) over a
359
three-minute observation period. Net revolutions min-1, either positive (clockwise) or
360
negative (anti-clockwise) were determined according to:
361
=
−
362 363
where T is the observation period of three minutes. The minimum acuity angle at which
364
optomotor responses were initiated (where revs min-1 first increased significantly from the
365
control 0° behaviour) was defined as the visual acuity threshold. A total of 9 and 8 fish were
366
examined in the ambient and elevated CO2 group respectively.
367 368 369 370
Statistical analysis 16
371
Anxiety trials
372
The effects of CO2 and temperature on percentage time spent in the black zone and
373
percentage time active (proportional data) were initially tested using generalized linear
374
mixed effects models (GLMMs) (family = binomial, link = logit). The effects of CO2 and
375
temperature treatment on velocity (right skewed continuous data) were also initially tested
376
using a GLMM (family = gamma, link = log). In all models CO2 and temperature were fixed
377
factors, standard length was included as a covariate and tank as a random factor. A range of
378
models were tested ranging from fully interactive to fully additive and the best one was
379
chosen based on Akaike information criterion (AIC). In all cases, the fully additive model
380
(Standard length+CO2+Temperature) came out as the best model. However, models were
381
under-dispersed and thus were re-run using a penalised quasi likelihood GLMM.
382 383 384
Behavioural lateralization
385
The effects of elevated CO2 on absolute and relative lateralization were tested using GLMMs
386
(family = binomial, link = logit) with rearing tank included as a random factor. The model for
387
absolute lateralization was weighted to the number of runs (10). The model for absolute
388
laterization was over-dispersed and thus re-run using a penalised quasi likelihood GLMM.
389
Finally, differences in the frequency distribution of relative lateralization scores between
390
ambient and elevated CO2 treatment was tested using a Kolmogorov-Smirnov test.
391 392 393
Vision
17
394
The effect of CO2 treatment on visual acuity was tested using a one-way repeated measures
395
ANOVA. Tank could not be included as a random factor due to the low level of replication in
396
this test.
397 398
Analysis packages
399
The LMM and GLMM analyses were conducted in R version 3.4.0 (R Core Team, 2017) using
400
the ‘lme4’,‘MASS’, ‘nlme’, ‘Car’ and ‘MuMin’ packages. The model outcomes presented
401
were obtained using the Anova function from the ‘Car’ package as opposed to the summary
402
function. This is because Type II testing was required as there were no significant
403
interactions present. The one-way repeated measures ANOVA was conducted in SPSS 25
404
(IBM, Armonk, USA). Please refer to the supplementary material to see all the models tested
405
and their outcomes.
406 407
Results
408
Anxiety trials
409
Percentage time spent in the black zone was significantly affected by CO2 treatment, with
410
fish reared under elevated CO2 spending 15.5% more time in the black zone compared with
411
control fish (Fig 1; χ2 = 3.91, df = 1, P = 0.048, effect size = 0.43 (Cohen’s d)). Temperature
412
treatment had no significant effect on percentage time spent in the black zone (χ2 = 0.37, df
413
= 1, P = 0.542). Finally, standard length had a significant effect on percentage time spent in
414
the black zone (χ2 = 12.21, df = 1, P < 0.001), with larger fish spending more time in the black
415
zone (R2 = 0.15, df = 1,142, P < 0.0001).
416
18
417
Active time ranged from 57.5 ± 3.2% in the ambient CO2 treatment at 21°C to 72.0 ± 3.0% in
418
the ambient CO2 treatment and 25°C (Fig 2A). Active time was not significantly affected by
419
either CO2 (χ2 = 0.039, df = 1, P = 0.844) or temperature (χ2 = 0.24, df = 1, P = 0.624)
420
treatment. Standard length had a significant effect on active time (χ2 = 15.47, df = 1, P <
421
0.0001), with larger fish spending a greater amount of time being active compared with
422
smaller fish (R2 = 0.16, df = 1,142, P < 0.0001).
423 424
Velocity ranged from 0.99 ± 0.05 cm s-1 in the ambient CO2 treatment at 21°C to 1.58 ± 0.16
425
cm s-1 in the ambient CO2 treatments at 25°C (Fig 2B). Velocity was not significantly affected
426
by either CO2 (χ2 = 0.470, df = 1, P = 0.493) or temperature (χ2 = 0.008, df = 1, P = 0.978)
427
treatment. Standard length had a significant effect on velocity (χ2 = 28.94, df = 1, P <
428
0.0001), with larger fish swimming at greater speeds (R2 = 0.25, df = 1,142, P < 0.0001).
429 430
431 19
432 433
Fig. 1. Effects of elevated CO2 and temperature on the percentage of time that juvenile yellowtail
434
kingfish, Seriola lalandi, spent in the black zone during the light/dark test (n = 36 per treatment).
435
Capital letters that differ represent significant differences between CO2 treatments. Bars represent
436
means ± 95% CI.
437 438
439 440 441
Fig. 2. Effects of elevated CO2 and temperature on (A) active time and (B) velocity of juvenile
442
yellowtail kingfish, S. lalandi, during the anxiety trials (n = 36 per treatment). Bars represent means ±
443
95% CI.
444 20
445 446 447 448 449
Behavioural lateralization
450
The S. lalandi used in this experiment were lateralized (mean absolute lateralization (LA) in
451
ambient fish = 44%), however, LA was not significantly different between the ambient and
452
elevated CO2 treatment (Fig 3a; χ2 = 2.96, df = 1, P = 0.085). Similarly, relative lateralization
453
(LR) was not significantly different between the ambient and elevated CO2 treatment (Fig 3b;
454
χ2 = 1.47, df = 1, P = 0.225). LR in the ambient and elevated CO2 treatments were -23.2 ±
455
6.3% and -31.6 ± 7.9% respectively. Finally, the frequency distribution of LR was not
456
significantly different between CO2 treatments (Fig 4; KS = 0.18, P = 0.393).
457 458
Fig 3. Effects of elevated CO2 on: (A) absolute lateralization (LA) and (B) relative lateralization (LR) in
459
juvenile yellowtail kingfish, S. lalandi (n = 50 per treatment) at elevated temperature (25°C).
460
Boxplots are sized according to the 25th and 75th quartiles, where the line identifies the median and
461
the whiskers indicate the minimum and maximum values. + signs represent means.
462 21
463 464
Fig 4. Frequency distributions for relative lateralization (LR) of juvenile S. lalandi at (A) ambient CO2
465
and (B) elevated CO2 at 25°C. Graphs show LR with positive and negative values indicating right and
466
left turns, respectively. The extreme values of -100indicate fish that turned in the same direction for
467
all 10 turns.
468 469 470 471
Vision CO2 treatment had no significant effect on visual acuity (Fig. 5; F = 0.053, df = 1, P = 0.821).
472
There was a significant effect of resolvable angle (Fig. 5; F = 23.96, df = 6, P < 0.001). The
473
number of net revolutions made by juvenile S. lalandi at resolvable angles greater than 6
474
degrees was significantly greater than those observed at angles less than 4 degrees (P <
475
0.05).
476 477
478 22
479 480
Fig 5. Effect of elevated CO2 on the visual acuity of juvenile S. lalandi at 21°C. White and grey points
481
represent ambient and elevated CO2 treatments respectively. Asterisks (*) represent a significant
482
difference from the control (0-degree background) within each of the CO2 treatments. Points
483
represent means ± 95% CI. Points are offset so that error bars can be clearly seen, reading were
484
taken at 0, 2, 3, 4, 6, 8 and 10 degrees.
485 486 487 488 489
Discussion More than 70 studies have shown that elevated CO2 can alter behavioural responses in
490
marine fishes (Munday et al., 2019). However, most studies have been conducted on small
491
benthic species and thus little is known about how predicted future CO2 levels might affect
492
the behaviours of large pelagic species. Even less is known about how elevated CO2 and
493
higher water temperatures may act concurrently on behavioural responses in large pelagic
494
fish. Here, we found that the effects of elevated CO2 on juvenile kingfish, Seriola lalandi,
495
were limited to anxiety. In contrast, elevated temperature had no significant effect on any
496
of the behaviours measured. Overall, our results suggest that juvenile yellowtail kingfish are
497
likely to be largely behaviourally tolerant to future ocean conditions.
498 499
Juvenile S. lalandi exhibited increased anxiety (or reduced boldness) when reared under
500
elevated CO2 conditions, spending a significantly greater proportion of time (+15.5%) in the
501
black zone during a standard light/dark test. Increased anxiety at elevated CO2 has also been
502
observed in Californian rockfish (Sebastes diploproa) using the light/dark test, although the
503
effect size was greater than observed in this study (Cohen’s d = 0.98) (Hamilton et al., 2014).
504
By contrast, another study that used the light/dark test reported no effect of elevated CO2
23
505
on anxiety in Californian blacksmiths (Chromis punctipinnis) (Kwan et al., 2017). Increased
506
anxiety has also been observed in three-spined stickleback (Gasterosteus aculeatus) (Jutfelt
507
et al., 2013) and barramundi (Lates calcarifer) (Rossi et al., 2015), in experimental tests
508
using a novel object and shelter test, respectively. Juvenile kingfish often hide from large
509
predators under floating debris or weed (dark patches). Thus, in a natural setting where
510
food availability is patchy and predators are present, this change in behaviour under
511
elevated CO2 might result in decreased foraging success due to more time spent hiding. This
512
could potentially impact growth and survival trajectories, although in a laboratory setting,
513
where food is available ad libitum, there appears to be limited effects of elevated CO2 on
514
growth and survival of S. lalandi early life stages (Watson et al., 2018). In contrast to anxiety,
515
no significant effect of elevated CO2 on routine activity was observed, which is consistent
516
with past works on the same species (Laubenstein et al., 2018; Munday et al., 2016) and
517
other pelagic species (Bignami et al., 2017, 2014)
518 519
In general, the reported effects of elevated CO2 on fish anxiety and activity are highly
520
variable, yet increased boldness/activity or no effects of elevated CO2 are most often
521
reported (Cattano et al., 2018). While species-specific responses may be partly responsible
522
for the lack of consistency between studies, methodological differences are also likely to be
523
an underlying factor. Indeed, our increased anxiety result contrasts with previous work on
524
the same species where no significant effect of elevated CO2 (1000 μatm) on boldness was
525
reported (Laubenstein et al., 2018). In the present study we used a light/dark test to
526
determine CO2 effects on anxiety, whereas an open field test was used by Laubenstein et al.
527
(2018), both of which are common methods for measuring anxiety in fish (Maximino et al.,
528
2010). Likewise, Hamilton et al. ( 2014) observed increased anxiety in juvenile Californian 24
529
rockfish reared under elevated CO2 (1125 μatm) in a light/dark test, but not in a shelter test.
530
These differing results between established anxiety tests highlight that care should be taken
531
when drawing conclusions about CO2 effects on behaviours, as a null effect could be related
532
to the methodology not being sensitive enough to detect differences as opposed to no
533
effects of elevated CO2. Open field tests with no stimulus, in particular, seem to give
534
extraordinarily variable results and are likely to be an unreliable test of elevated CO2 effects
535
on anxiety/activity (Munday et al., 2019). Future studies, especially those investigating
536
untested species or only one behaviour, should therefore consider using multiple methods
537
to test the same behaviour to more accurately assess behavioural sensitivity to ocean
538
acidification. Alternatively, a diverse range of behavioural responses could be tested.
539 540
In contrast to elevated CO2, high temperature had no effect on anxiety of juvenile S. lalandi,
541
which is consistent with a previous study on the same species (Laubenstein et al., 2018). We
542
also found no significant effect of high temperature on routine activity. This was surprising
543
as routine activity and temperature are often closely correlated, due to effects that
544
temperature has on metabolic rates and energy demands. For example, at high temperature
545
fish may increase their activity to locate more food so that they can offset the increased
546
metabolic costs associated with living at a higher temperatures (Biro et al., 2010).
547
Conversely, if temperatures are too high fish may reduce their activity as an energy-saving
548
strategy (Jarrold and Munday, 2018a; Johansen and Jones, 2011). Laubenstein et al. (2018)
549
documented a 20% increase in resting metabolic rates of juvenile S. lalandi reared at 25°C
550
compared with 21°C, demonstrating a greater cost of living at high temperature, in addition
551
to significantly increased (55%) activity. The reason for contrasting routine activity results
552
between studies is unclear but may be related to the methodological differences described 25
553
above (open field test vs. light/dark test). Indeed, there is a 10% difference in the
554
percentage of time fish were active at 25°C between studies, with Laubenstein et al. (2018)
555
reporting higher activity levels. Considering these two studies used similarly aged fish from
556
the same experiment, this variability may be driven by differences in anxiety related activity
557
between the two experimental setups (open field vs light/dark test). It may be that fish are
558
more anxious in an open field test, with no shelter or dark area, which could lead to
559
hyperactivity (Kysil et al., 2017; Maximino et al., 2010).
560 561
Behavioural lateralization has been linked to higher performance in cognitive tasks, visual
562
assessment, schooling behaviour and escape reactivity in other fish (Bisazza and Dadda,
563
2005; Dadda et al., 2010; Dadda and Bisazza, 2006; Sovrano et al., 1999). We detected no
564
significant effect of elevated CO2 on absolute lateralization (LA). However, there was trend
565
on increased LA at elevated CO2 compared to control conditions (54% vs. 44%). A significant
566
increase in LA was reported in small-spotted catsharks (Scyliorhinus canicula) (Green and
567
Jutfelt, 2014) and zebrafish (Danio rerio) (Vossen et al., 2016) at elevated CO2. However,
568
most studies have reported either decreased (e.g. Jutfelt et al., 2013; Maulvault et al.,
569
2018; Welch et al., 2014) or unchanged (e.g. Hamilton et al., 2017; Silva et al., 2018; Tix et
570
al., 2017) LA under elevated CO2. We also observed no significant effect of elevated CO2 on
571
relative lateralization (LR), although similarly to LA there was a trend of increased LR at
572
elevated CO2 compared to control conditions (-32% vs. -23%). Non-significant effects of
573
elevated CO2 on LR have been reported in a number of other species including blue rockfish,
574
damselfish species and Atlantic cod (Domenici et al., 2012; Hamilton et al., 2017; Jarrold et
575
al., 2017; Jutfelt and Hedgärde, 2015; Schmidt et al., 2017). Unfortunately, we were only
576
able to conduct lateralization trials on fish reared at elevated temperature (25°C) as those 26
577
reared under control temperature (21°C) were too small for the testing arena. Thus, we
578
cannot exclude the possibility that elevated temperature may have affected our observed
579
lateralization results. However, out of the few studies that have tested the combined effects
580
of elevated CO2 and temperature on behavioural lateralization none have reported a
581
significant effect of elevated temperature (in isolation or in combination with CO2) on LA
582
(Domenici et al., 2014; Jarrold and Munday, 2018b; Schmidt et al., 2017) and only one has
583
reported a significant interactive effect between CO2 and temperature on LR (Domenici et
584
al., 2014). Importantly, here we show that the more realistic future conditions of elevated
585
CO2 and temperature in combination had no significant effects on behavioural lateralization
586
in juvenile kingfish.
587 588
Fish rely on visual cues to provide accurate information about risk in both space and time
589
(Ferrari et al., 2010). Therefore, any impairment to the visual system could have important
590
consequences for individual performance. Using an optomotor test, we show that the visual
591
acuity of juvenile S. lalandi was unaffected by elevated CO2. These results contrast with
592
some previous work where negative effects of elevated CO2 on fish vision have been
593
reported. For example, Chung et al. (2014) found that continuous exposure to elevated CO2
594
slowed retinal function in a coral reef damselfish, potentially impairing the capacity of fish
595
to react to fast events. Indeed, experiments have shown that juvenile damselfish exposed to
596
elevated CO2 have reduced visual perception and are slower to react to a predator ambush
597
(Allan et al., 2013; Ferrari et al., 2012). More recently, fish reared in a mesocosm setup at
598
elevated CO2 (910 μatm) showed impaired visual function when the sense was tested in
599
isolation, although this negative effect was not present when fish were tested under a
600
higher level of ecological complexity (Goldenberg et al., 2018). It is possible that the low 27
601
level of replication used here (n = 8-9) could have limited our capacity to detect an effect,
602
although, Chung et al. (2014) used a lower level of replication (n = 5) and still observed
603
significant CO2 effects. It may also be possible that he ability of kingfish to maintain a
604
visually mediated optomotor response under elevated CO2 is linked to preserving fast
605
schooling reactions, a behaviour that is very important for the general success of this
606
species in the pelagic realm. To date, only a few studies have tested visual effects, and this is
607
the first study to use an optomotor test to compare visual acuity between treatments. More
608
studies are needed before any general trends regarding the effect of elevated CO2 on vision
609
can be established.
610 611 612
Here, we report that behavioural responses to elevated CO2 in juvenile S. lalandi are varied,
613
with anxiety the only behaviour to be significantly affected. Similar variability in behavioural
614
responses to elevated CO2 have been observed in other studies (Jarrold and Munday,
615
2018a; Schmidt et al., 2017; Sundin and Jutfelt, 2015). The behavioural changes observed in
616
fish at elevated CO2 appear to be caused by an interference with the GABAA receptor
617
(Nilsson et al., 2012), the primary inhibitory neurotransmitter receptor in the vertebrate
618
brain. The GABAA receptor is an ion-channel with conductance for Cl- and HCO3−. Under
619
elevated CO2, fishes increase intracellular and extracellular HCO3- concentrations, with a
620
corresponding decrease in Cl-, to prevent plasma and tissue acidosis (Baker et al., 2009;
621
Heuer and Grosell, 2014). This altered ion gradient is thought to turn some GABAA receptors
622
from inhibitory to excitatory, ultimately leading to behavioural impairments (Heuer et al.,
623
2016; Heuer and Grosell, 2014). Given the ubiquity of GABAA receptors in animal nervous
624
systems the underlying reason for why some behaviours are affected by elevated CO2 while 28
625
others are not is unclear. While methodological differences may potentially be a factor, it is
626
also possible that there are other physiological mechanisms responsible for causing
627
behavioural alterations in fish at elevated CO2. For example, altered stress hormone levels,
628
such as cortisol and serotonin, are known to directly correlate with activity and anxiety-
629
associated behaviours in fish (Cachat et al., 2010; Egan et al., 2009; Winberg and Nilsson,
630
1993) and a recent study has correlated changes in dopamine and serotonin concentration
631
in the brain with impaired mutualistic interactions in cleaner fishes under elevated CO2
632
(Paula et al., 2019). Alternatively, different sensory systems, and their associated
633
behaviours, may simply have different sensitivities to the altered Cl- and HCO3−
634
concentrations associated with elevated CO2. More studies that investigate the underlying
635
physiological mechanisms behind behavioural sensitivity and tolerance at elevated CO2 are
636
urgently needed. Results from such studies may help to explain why there has been so much
637
behaviour- and species-specific variation in behavioural responses to elevated CO2 observed
638
to date (Cattano et al., 2018).
639 640
In conclusion, the results of this study indicate that juvenile yellowtail kingfish are, in
641
general, behaviourally tolerant to projected near-future CO2 levels as only one behaviour
642
tested was affected. The limited effects of elevated CO2 on behaviours observed here is
643
consistent with past studies on the same species (Laubenstein et al., 2018; Munday et al.,
644
2016). Watson et al. (2018) observed negative effects on escape performance and
645
swimming ability in fish from the same experiment; however, it is important to note that the
646
purely decision/sensory based aspects of the fast starts (latency to react to the stimulus and
647
direction turned) were not affected by elevated CO2. Thus, for juvenile yellowtail kingfish it
648
appears that behaviours that are solely decision/sensory based are less sensitive to elevated 29
649
CO2 compared to those that are more closely linked to metabolic capacity. In general, these
650
results contrast with the expectation that large pelagic fish will be more susceptible to
651
elevated CO2, compared with benthic species, due to the relatively stable environment they
652
live in (Munday et al., 2008; Nilsson et al., 2012). It is possible that the behavioural tolerance
653
of large pelagic fish stems from the fact that they are physiologically adapted to cope with
654
high levels of metabolic CO2 due to their highly active lifestyle. Unfortunately, we were not
655
able to test the effects of high temperature on every behaviour due to logistical issues
656
relating to fish size. However, those behaviours that were tested (anxiety and activity)
657
showed no effects, indicating that juvenile yellowtail kingfish may be behaviourally tolerant
658
to temperature conditions predicted to occur by the year 2100. However, other recent
659
studies on juvenile kingfish have reported significant effects of elevated temperature on
660
some behaviours (routine activity and escape performance) and physiological traits
661
(metabolic rates and critical swimming speeds) (Laubenstein et al., 2018; Watson et al.,
662
2018). Taken together, these recent studies on yellowtail kingfish indicate that this species is
663
likely to be sensitive to future ocean conditions, especially ocean warming. Given the
664
ecological and economic importance of large pelagic fish species more studies investigating
665
the combined effects of elevated CO2 and temperature are urgently needed. Results from
666
such studies will be critical for implementing adaptation and mitigation responses relating
667
to fisheries management.
668 669
Acknowledgments: We thank Michael Exton, Simon Griffiths, David McQueen, Alvin
670
Setiawan, and Carly Wilson for assistance with fish husbandry and maintaining the
671
experiments. We thank Kim Currie and the University of Otago Research Centre for
672
Oceanography for water sample analysis. Finally, we thank Professor Rhondda Jones for 30
673
statistical support. This project was supported by funding from the South Pacific Regional
674
Environment Programme (SPREP) and the Pacific Community (SPC) Pacific Islands Ocean
675
Acidification Partnership (PIOAP). The PIOAP project was funded by the Government of New
676
Zealand and the Principality of Monaco (PIOAP). This project was also supported by funding
677
from the Australian Research Council (FT130100505), the ARC Centre of Excellence for Coral
678
Reef Studies, and NIWA.
679 680
References
681
Allan, B.J.M., Domenici, P., McCormick, M.I., Watson, S.-A., Munday, P.L., 2013. Elevated
682
CO2 affects predator-prey interactions through altered performance. PLoS One 8,
683
e58520. https://doi.org/10.1371/journal.pone.0058520.
684
Allan, B.J.M., Domenici, P., Watson, S.-A., Munday, P.L., McCormick, M.I., 2017. Warming
685
has a greater effect than elevated CO2 on predator–prey interactions in coral reef fish.
686
Proc. R. Soc. B Biol. Sci. 284, 20170784. https://doi.org/10.1098/rspb.2017.0784.
687
Baker, D.W., Matey, V., Huynh, K.T., Wilson, J.M., Morgan, J.D., Brauner, C.J., 2009.
688
Complete intracellular pH protection during extracellular pH depression is associated
689
with hypercarbia tolerance in white sturgeon, Acipenser transmontanus. Am. J. Physiol.
690
Regul. Integr. Comp. Physiol. 296, 1868–1880.
691
https://doi.org/10.1152/ajpregu.90767.2008.
692
Bignami, S., Sponaugle, S., Cowen, R.K., 2014. Effects of ocean acidification on the larvae of
693
a high-value pelagic fisheries species, Mahi-mahi Coryphaena hippurus. Aquat. Biol. 21,
694
249–260. https://doi.org/10.3354/ab00598.
695
Bignami, S., Sponaugle, S., Cowen, R.K., 2013. Response to ocean acidification in larvae of a
31
696
large tropical marine fish, Rachycentron canadum. Glob. Chang. Biol. 19, 996–1006.
697
https://doi.org/10.1111/gcb.12133.
698
Bignami, S., Sponaugle, S., Hauff, M., Cowen, R.K., 2017. Combined effects of elevated pCO2,
699
temperature, and starvation stress on larvae of a large tropical marine fish. ICES J. Mar.
700
Sci. 74, 1220–1229. https://doi.org/10.1093/icesjms/fsw216.
701
Biro, P.A., Beckmann, C., Stamps, J.A., 2010. Small within-day increases in temperature
702
affects boldness and alters personality in coral reef fish. Proc. R. Soc. B Biol. Sci. 277,
703
71–77. https://doi.org/10.1098/rspb.2009.1346.
704 705 706 707
Bisazza, A., Dadda, M., 2005. Enhanced schooling performance in lateralized fishes. Proc. R. Soc. B Biol. Sci. 272, 1677–1681. https://doi.org/10.1098/rspb.2005.3145. Brauner, C.J., 2009. Acid-base balance. In: Finn RN, Kapoor BG (eds) Fish larval physiology. Science Publishers, Enfield, NH, p 185–198. https://doi.org/10.1016/j.tree.2006.11.002
708
Bromhead, D., Scholey, V., Nicol, S., Margulies, D., Wexler, J., Stein, M., Hoyle, S., Lennert-
709
Cody, C., Williamson, J., Havenhand, J., Ilyina, T., Lehodey, P., 2015. The potential
710
impact of ocean acidification upon eggs and larvae of yellowfin tuna (Thunnus
711
albacares). Deep. Res. Part II Top. Stud. Oceanogr. 113, 268–279.
712
https://doi.org/10.1016/j.dsr2.2014.03.019.
713
Cachat, J., Stewart, A., Grossman, L., Gaikwad, S., Kadri, F., Chung, K.M., Wu, N., Wong, K.,
714
Roy, S., Suciu, C., Goodspeed, J., Elegante, M., Bartels, B., Elkhayat, S., Tien, D., Tan, J.,
715
Denmark, A., Gilder, T., Kyzar, E., Dileo, J., Frank, K., Chang, K., Utterback, E., Hart, P.,
716
Kalueff, A. V., 2010. Measuring behavioral and endocrine responses to novelty stress in
717
adult zebrafish. Nat. Protoc. 5, 1786–1799. https://doi.org/10.1038/nprot.2010.140.
718
Casini, M., Hjelm, J., Molinero, J.-C., Lovgren, J., Cardinale, M., Bartolino, V., Belgrano, A.,
719
Kornilovs, G., 2009. Trophic cascades promote threshold-like shifts in pelagic marine 32
720
ecosystems. Proc. Natl. Acad. Sci. USA 106, 197–202.
721
https://doi.org/10.1073/pnas.0806649105.
722
Cattano, C., Calò, A., Di Franco, A., Firmamento, R., Quattrocchi, F., Sdiri, K., Guidetti, P.,
723
Milazzo, M., 2017. Ocean acidification does not impair predator recognition but
724
increases juvenile growth in a temperate wrasse off CO2 seeps. Mar. Environ. Res. 132,
725
33–40. https://doi.org/10.1016/j.marenvres.2017.10.013.
726
Cattano, C., Claudet, J., Domenici, P., Milazzo, M., 2018. Living in a high CO2 world: a global
727
meta-analysis shows multiple trait-mediated responses of fish to ocean acidification.
728
Ecol. Monogr. 88, 320-335. https://doi.org/10.1002/ecm.1297.
729
Chivers, D.P., McCormick, M.I., Nilsson, G.E., Munday, P.L., Watson, S.-A., Meekan, M.G.,
730
Mitchell, M.D., Corkill, K.C., Ferrari, M.C.O., 2014. Impaired learning of predators and
731
lower prey survival under elevated CO2 : a consequence of neurotransmitter
732
interference. Glob. Chang. Biol. 20, 515–522. https://doi.org/10.1111/gcb.12291.
733
Chung, W.-S., Marshall, N.J., Watson, S.-A., Munday, P.L., Nilsson, G.E., 2014. Ocean
734
acidification slows retinal function in a damselfish through interference with GABAA
735
receptors. J. Exp. Biol. 217, 323–326. https://doi.org/10.1242/jeb.092478.
736
Clements, J.C., Hunt, H.L., 2015. Marine animal behaviour in a high CO2 ocean Marine animal
737
behaviour in a high CO 2 ocean. Mar. Ecol. Prog. Ser. 536, 259–279.
738
https://doi.org/10.3354/meps11426.
739
Collins, M., Knutti, R., Arblaster, J., Dufresne, J.-L., Fichefet, T., Friedlingstein, P., Gao, X.,
740
Gutowski, W.J., Johns, T., Krinner, G., Shongwe, M., Tebaldi, C., Weaver, A.J.,
741
Wehner, M., 2013. Long-term Climate Change: Projections, Commitments and
742
Irreversibility. In T. F. Stocker, D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J.
743
Boschung, A. Nauels, Y. Xia, V. Bex, & P. M. Midgley (Eds.), Climate change 2013: 33
744
The physical science basis. contribution of working group i to the fifth assessment
745
report of the intergovernmental panel on climate change (pp. 1029–1136). Cambridge,
746
UK and New York, NY: Cambridge University Press.
747
Dadda, M., Bisazza, A., 2006. Lateralized female topminnows can forage and attend to a
748
harassing male simultaneously. Behav. Ecol. 17, 358–363.
749
https://doi.org/10.1093/beheco/arj040.
750
Dadda, M., Koolhaas, W.H., Domenici, P., 2010. Behavioural asymmetry affects escape
751
performance in a teleost fish. Biol. Lett. 6, 414–417.
752
https://doi.org/10.1098/rsbl.2009.0904.
753
Dickson, A.G., 1990. Standard potential of the reaction: AgCl(s) + 1/2H2(g) = Ag(s) + HCl(aq),
754
and and the standard acidity constant of the ion HSO4− in synthetic sea water from
755
273.15 to 318.15 K. J. Chem. Thermodyn. 22, 113–127. https://doi.org/10.1016/0021-
756
9614(90)90074-Z.
757
Dickson, A.G., Millero, F.J., 1987. A comparison of the equilibrium constants for the
758
dissociation of carbonic acid in seawater media. Deep Sea Res. Part A. Oceanogr. Res.
759
Pap. 34, 1733–1743. https://doi.org/10.1016/0198-0149(87)90021-5.
760
Domenici, P., Allan, B., McCormick, M.I., Munday, P.L., 2012. Elevated carbon dioxide affects
761
behavioural lateralization in a coral reef fish. Biol. Lett. 8, 78–81.
762
https://doi.org/10.1098/rsbl.2011.0591.
763
Domenici, P., Allan, B.J.M., Watson, S.-A., McCormick, M.I., Munday, P.L., 2014. Shifting
764
from right to left: the combined effect of elevated CO2 and temperature on behavioural
765
lateralization in a coral reef fish. PLoS One 9, e87969.
766
https://doi.org/10.1371/journal.pone.0087969,
767
Doney, S.C., Fabry, V.J., Feely, R.A., Kleypas, J.A., 2009. Ocean Acidification: the other CO2 34
768
Problem. Ann. Rev. Mar. Sci. 1, 169–192.
769
https://doi.org/10.1146/annurev.marine.010908.163834.
770
Egan, R.J., Bergner, C.L., Hart, P.C., Cachat, J.M., Canavello, P.R., Elegante, M.F., Elkhayat,
771
S.I., Bartels, B.K., Tien, A.K., Tien, D.H., Mohnot, S., Beeson, E., Glasgow, E., Amri, H.,
772
Zukowska, Z., Kalueff, A. V., 2009. Understanding behavioral and physiological
773
phenotypes of stress and anxiety in zebrafish. Behav. Brain Res. 205, 38–44.
774
https://doi.org/10.1016/j.bbr.2009.06.022.
775
Enders, E.C., Boisclair, D., 2016. Effects of environmental fluctuations on fish metabolism:
776
Atlantic salmon Salmo salar as a case study. J. Fish Biol. 88, 344–358.
777
https://doi.org/10.1111/jfb.12786.
778 779 780
FAO. The State of World Fisheries and Aquaculture. Contributing to food security and nutrition for all; FAO: Rome, Italy, 2016. Ferrari, M.C.O., Dixson, D.L., Munday, P.L., Mccormick, M.I., Meekan, M.G., Sih, A., Chivers,
781
D.P., 2011. Intrageneric variation in antipredator responses of coral reef fishes affected
782
by ocean acidification: implications for climate change projections on marine
783
communities. Glob. Chang. Biol. 17, 2980–2986. https://doi.org/10.1111/j.1365-
784
2486.2011.02439.x.
785
Ferrari, M.C.O., McCormick, M.I., Munday, P.L., Meekan, M.G., Dixson, D.L., Lönnstedt, O.,
786
Chivers, D.P., 2012. Effects of ocean acidification on visual risk assessment in coral reef
787
fishes. Funct. Ecol. 26, 553–558. https://doi.org/10.1111/j.1365-2435.2011.01951.x.
788
Ferrari, M.C.O., Munday, P.L., Rummer, J.L., McCormick, M.I., Corkill, K., Watson, S.-A., Allan,
789
B.J.M., Meekan, M.G., Chivers, D.P., 2015. Interactive effects of ocean acidification and
790
rising sea temperatures alter predation rate and predator selectivity in reef fish
791
communities. Glob. Chang. Biol. 21, 1848–1855. https://doi.org/10.1111/gcb.12818. 35
792
Ferrari, M.C.O., Wisenden, B.D., Chivers, D.P., 2010. Chemical ecology of predator – prey
793
interactions in aquatic ecosystems: a review and prospectus. Canadain J. Zool. 724,
794
698–724. https://doi.org/10.1139/Z10-029.
795
Frank, K.T., Petrie, B., Choi, J.S., Leggett, W.C., 2005. Trophic cascades in a formerly cod-
796
dominated ecosystem. Science. 308, 1621–1623.
797
https://doi.org/10.1126/science.1113075.
798
Gallego, M.A., Timmermann, A., Friedrich, T., Zeebe, R.E., 2018. Drivers of future seasonal
799
cycle changes of oceanic pCO2. Biogeosciences 15, 5315–5327.
800
https://doi.org/10.5194/bg-2018-212.
801
Goldenberg, S.U., Nagelkerken, I., Marangon, E., Bonnet, A., Ferreira, C.M., Connell, S.D.,
802
2018. Ecological complexity buffers the impacts of future climate on marine
803
consumers. Nat. Clim. Chang. 8, 229–233. https://doi.org/10.1038/s41558-018-0086-0.
804
Green, L., Jutfelt, F., 2014. Elevated carbon dioxide alters the plasma composition and
805
behaviour of a shark. Biol. Lett. 10, 20140538. https://doi.org/10.1098/rsbl.2014.0538.
806
Hamilton, S.L., Logan, C.A., Fennie, H.W., Sogard, S.M., Barry, J.P., Makukhov, A.D., Tobosa,
807
L.R., Boyer, K., Lovera, C.F., Bernardi, G., 2017. Species-specific responses of juvenile
808
rockfish to elevated pCO2: from behavior to genomics. PLoS One 12, e0169670.
809
https://doi.org/10.1371/journal. pone.0169670.
810
Hamilton, T.J., Holcombe, A., Tresguerres, M., 2014. CO2-induced ocean acidification
811
increases anxiety in Rockfish via alteration of GABAA receptor functioning. Proc. R. Soc.
812
281, 20132509. https://doi.org/10.1098/rspb.2013.2509.
813
Heinrich, D.D.U., Watson, S.-A., Rummer, J.L., Brandl, S.J., Simpfendorfer, C.A., Heupel, M.R.,
814
Munday, P.L., 2016. Foraging behaviour of the epaulette shark Hemiscyllium ocellatum
815
is not affected by elevated CO2. ICES J. Mar. Sci. 73, 633–640. 36
816 817
https://doi.org/10.1093/icesjms/fss153. Herbert, N.A., Wells, R.M.G., 2002. The effect of strenuous exercise and β-adrenergic
818
blockade on the visual performance of juvenile rainbow trout, Oncorhynchus mykiss. J.
819
Comp. Physiol. B Biochem. Syst. Environ. Physiol. 172, 725–731.
820
https://doi.org/10.1007/s00360-002-0303-y.
821
Heuer, R.M., Grosell, M., 2014. Physiological impacts of elevated carbon dioxide and ocean
822
acidification on fish. Am. J. Physiol. Regul. Integr. Comp. Physiol. 307, R1061–R1084.
823
https://doi.org/10.1152/ajpregu.00064.2014.
824
Heuer, R.M., Welch, M.J., Rummer, J.L., Munday, P.L., Grosell, M., 2016. Altered brain ion
825
gradients following compensation for elevated CO2 are linked to behavioural
826
alterations in a coral reef fish. Sci. Rep. 6, 33216. https://doi.org/10.1038/srep33216.
827
Hofmann, G.E., Smith, J.E., Johnson, K.S., Send, U., Levin, L.A., Paytan, A., Price, N.N.,
828
Peterson, B., Takeshita, Y., Matson, P.G., Crook, E.D., Kroeker, K.J., Gambi, M.C., Rivest,
829
E.B., Frieder, C.A., Yu, P.C., Martz, T.R., 2011. High-frequency dynamics of ocean pH: a
830
multi-ecosystem comparison. PLoS One 6, e28983.
831
https://doi.org/10.1371/journal.pone.0028983.
832
Jarrold, M.D., Humphrey, C., McCormick, M.I., Munday, P.L., 2017. Diel CO2 cycles reduce
833
severity of behavioural abnormalities in coral reef fish under ocean acidification. Sci.
834
Rep. 7, 10153. https://doi.org/10.1038/s41598-017-10378-y.
835
Jarrold, M.D., Munday, P.L., 2018a. Elevated temperature does not substantially modify the
836
interactive effects between elevated CO2 and diel CO2 cycles on the survival, growth
837
and behavior of a coral reef fish. Front. Mar. Sci. 5, 458. doi:
838
10.3389/fmars.2018.00458. https://doi.org/10.3389/fmars.2018.00458.
839
Johansen, J.L., Jones, G.P., 2011. Increasing ocean temperature reduces the metabolic 37
840
performance and swimming ability of coral reef damselfishes. Glob. Chang. Biol. 17,
841
2971–2979. https://doi.org/10.1111/j.1365-2486.2011.02436.x.
842
Jutfelt, F., Bresolin de Souza, K., Vuylsteke, A., Sturve, J., 2013. Behavioural disturbances in a
843
temperate fish exposed to sustained high-CO2 Levels. PLoS One 8, e65825.
844
https://doi.org/10.1371/journal.pone.0065825.
845
Jutfelt, F., Hedgärde, M., 2015. Juvenile Atlantic cod behavior appears robust to near-future
846
CO2 levels. Front. Zool. 12, 11. doi: https://doi.org/10.1186/s12983-015-0104-2.
847
Killen, S.S., Atkinson, D., Glazier, D.S., 2010. The intraspecific scaling of metabolic rate with
848
body mass in fishes depends on lifestyle and temperature. Ecol. Lett. 13, 184–193.
849
https://doi.org/10.1111/j.1461-0248.2009.01415.x.
850
Kwan, G.T., Hamilton, T.J., Tresguerres, M., 2017. CO2-induced ocean acidification does not
851
affect individual or group behaviour in a temperate damselfish. R. Soc. Open Sci. 4,
852
170283. https://doi.org/10.1098/rsos.170283.
853
Kwiatkowski, L., Orr, J.C., 2018. Diverging seasonal extremes for ocean acidification during
854
the twenty-first century. Nat. Clim. Chang. 8, 141–145.
855
https://doi.org/10.1038/s41558-017-0054-0.
856
Kysil, E. V., Meshalkina, D.A., Frick, E.E., Echevarria, D.J., Rosemberg, D.B., Maximino, C.,
857
Lima, M.G., Abreu, M.S., Giacomini, A.C., Barcellos, L.J.G., Song, C., Kalueff, A. V., 2017.
858
Comparative analyses of zebrafish anxiety-like behavior using conflict-based novelty
859
tests. Zebrafish 14, 197–208. https://doi.org/10.1089/zeb.2016.1415.
860
Laubenstein, T., Rummer, J., Nicol, S., Parsons, D., Pether, S., Pope, S., Smith, N., Munday, P.,
861
2018. Correlated effects of ocean acidification and warming on behavioral and
862
metabolic traits of a large pelagic fish. Diversity 10, 35.
863
https://doi.org/10.3390/d10020035. 38
864
Lopes, A.F., Morais, P., Pimentel, M., Rosa, R., Munday, P.L., Goncalves, E.J., Faria, A.M.,
865
2016. Behavioural lateralization and shoaling cohesion of fish larvae altered under
866
ocean acidification. Mar. Biol. 163, 243. https://doi.org/10.1007/s00227-016-3026-4.
867
Maulvault, A.L., Santos, L.H.M.L.M., Paula, J.R., Camacho, C., Pissarra, V., Fogaça, F.,
868
Barbosa, V., Alves, R., Ferreira, P.P., Barceló, D., Rodriguez-Mozaz, S., Marques, A.,
869
Diniz, M., Rosa, R., 2018. Differential behavioural responses to venlafaxine exposure
870
route, warming and acidification in juvenile fish (Argyrosomus regius). Sci. Total
871
Environ. 634, 1136–1147. https://doi.org/10.1016/j.scitotenv.2018.04.015.
872
Maximino, C., da Silva, A.W.B., Gouveia, A., Herculano, A.M., 2011. Pharmacological analysis
873
of zebrafish (Danio rerio) scototaxis. Prog. Neuro-Psychopharmacology Biol. Psychiatry
874
35, 624–631. https://doi.org/10.1016/j.pnpbp.2011.01.006.
875
Maximino, C., de Brito, T.M., da Silva Batista, A.W., Herculano, A.M., Morato, S., Gouveia, A.,
876
2010. Measuring anxiety in zebrafish: a critical review. Behav. Brain Res. 214, 157–171.
877
https://doi.org/10.1016/j.bbr.2010.05.031.
878
Maximino, C., Puty, B., Benzecry, R., Araújo, J., Lima, M.G., De Jesus Oliveira Batista, E.,
879
Renata De Matos Oliveira, K., Crespo-Lopez, M.E., Herculano, A.M., 2013. Role of
880
serotonin in zebrafish (Danio rerio) anxiety: relationship with serotonin levels and
881
effect of buspirone, WAY 100635, SB 224289, fluoxetine and para-chlorophenylalanine
882
(pCPA) in two behavioral models. Neuropharmacology 71, 83–97.
883
https://doi.org/10.1016/j.neuropharm.2013.03.006.
884
McKenzie, J.R., 2014. Review of productivity parameters and stock assessment options for
885
kingfish (Seriola lalandi lalandi). New Zealand Fisheries Assessment Report 2014/04.
886
Ministry for Primary Industries, Wellington, New Zealand.
887
McKenzie, J.R., Smith, M., Watson, T., Francis, M., Ó Maolagáin, C., Poortenaar, C., 39
888
Holdsworth, J., 2014. Age, growth, maturity and natural mortality of New Zealand
889
kingfish (Seriola lalandi lalandi). Wellington, New Zealand: Ministry for Primary
890
Industries.
891
McNeil, B.I., Sasse, T.P., 2016. Future ocean hypercapnia driven by anthropogenic
892
amplification of the natural CO2 cycle. Nature 529, 383–386.
893
https://doi.org/10.1038/nature16156.
894
Mehrbach, C., Culberson, C.H., Hawley, J.E., Pytkowicz, R.M., 1973. Measurement of the
895
apparent dissociation constants of carbonic acid in seawater at atmospheric pressure.
896
Limnol. Oceanogr. 18, 897–907. https://doi.org/10.4319/lo.1973.18.6.0897.
897
Meinshausen, M., Smith, S.J., Calvin, K., Daniel, J.S., Kainuma, M.L.T., 2011. The RCP
898
greenhouse gas concentrations and their extensions from 1765 to 2300. Clim. Change
899
109, 213–241. https://doi.org/10.1007/s10584-011-0156-z.
900
Melzner, F., Gutowska, M.A., Langenbuch, M., Dupont, S., Lucassen, M., Thorndyke, M.C.,
901
Bleich, M., Portner, H.-O., 2009. Physiological basis for high CO2 tolerance in marine
902
ectothermic animals: pre-adaptation through lifestyle and ontogeny? Biogeosciences 6,
903
2313–2331. https://doi.org/10.5194/bg-6-2313-2009.
904
Mezzomo, N.J., Silveira, A., Giuliani, G.S., Quadros, V.A., Rosemberg, D.B., 2016. The role of
905
taurine on anxiety-like behaviors in zebrafish: a comparative study using the novel tank
906
and the light-dark tasks. Neurosci. Lett. 613, 19–24.
907
https://doi.org/10.1016/j.neulet.2015.12.037.
908
Munday, P.L., Dixson, D.L., McCormick, M.I., Meekan, M., Ferrari, M.C.O., Chivers, D.P.,
909
2010. Replenishment of fish populations is threatened by ocean acidification. Proc.
910
Natl. Acad. Sci. USA. 107, 12930–12934. https://doi.org/10.1073/pnas.1004519107.
911
Munday, Philip L, Jarrold, M.D., Nagelkerken, I., 2019. Ecological effects of elevated CO2 on 40
912
marine and freshwater fishes: from individual to community effects, Fish physiology
913
Carbon dioxide Vol 37 (Eds Grosell. M, Munday. P, Farrell. A and Brauner. C). Elseiver,
914
Amsterdam.
915
Munday, P.L., Jones, G.P., Pratchett, M.S., Williams, A.J., 2008. Climate change and the
916
future for coral reef fishes. Fish and Fish. 9, 261–285. https://doi.org/10.1111/j.1467-
917
2979.2008.00281.x.
918
Munday, P.L., McCormick, M.I., Meekan, M., Dixson, D.L., Watson, S.-A., Chivers, D.P.,
919
Ferrari, M.C.O., 2012. Selective mortality associated with variation in CO2 tolerance in a
920
marine fish. Ocean Acidif. 1, 1–5. https://doi.org/10.2478/oac-2012-0001.
921
Munday, Phillip L., Schunter, C., Allan, B.J.M., Nicol, S., Parsons, D.M., Pether, S.M.J., Pope,
922
S., Ravasi, T., Setiawan, A.N., Smith, N., Domingos, J.A., 2019. Testing the adaptive
923
potential of yellowtail kingfish to ocean warming and acidification. Front. Ecol. Evol. 7,
924
253. https://doi: 10.3389/fevo.2019.00253.
925
Munday, P.L., Watson, S.-A., Parsons, D.M., King, A., Barr, N.G., McLeod, I.M., Allan, B.J.M.,
926
Pether, S.M.J., 2016. Effects of elevated CO2 on early life history development of the
927
yellowtail kingfish, Seriola lalandi, a large pelagic fish. ICES J. Mar. Sci. 73, 641–649.
928
https://doi.org/10.1093/icesjms/fsv210.
929
Nagelkerken, I., Munday, P.L., 2016. Animal behaviour shapes the ecological effects of ocean
930
acidification and warming : moving from individual to community-level responses.
931
Glob. Chang. Biol. 22, 974–989. https://doi.org/10.1111/gcb.13167.
932
Näslund, J., Lindström, E., Lai, F., Jutfelt, F., 2015. Behavioural responses to simulated bird
933
attacks in marine three-spined sticklebacks after exposure to high CO2 levels. Mar
934
Freshwater Res. 66, 877–885. https://doi.org/10.1071/MF14144.
935
Nilsson, G.E., Dixson, D.L., Domenici, P., McCormick, M.I., Sørensen, C., Watson, S.-A., 41
936
Munday, P.L., 2012. Near-future carbon dioxide levels alter fish behaviour by
937
interfering with neurotransmitter function. Nat. Clim. Chang. 2, 201–204.
938
https://doi.org/10.1038/nclimate1352.
939
Nowicki, J.P., Miller, G.M., Munday, P.L., 2012. Interactive effects of elevated temperature
940
and CO2 on foraging behavior of juvenile coral reef fish. J. Exp. Mar. Bio. Ecol. 412, 46–
941
51. https://doi.org/10.1016/j.jembe.2011.10.020.
942
Orr, J.C., Fabry, V.J., Aumont, O., Bopp, L., Doney, S.C., Feely, R.A., Gnanadesikan, A.,
943
Gruber, N., Ishida, A., Joos, F., Key, R.M., Lindsay, K., Maier-Reimer, E., Matear, R.,
944
Monfray, P., Mouchet, A., Najjar, R.G., Plattner, G.K., Rodgers, K.B., Sabine, C.L.,
945
Sarmiento, J.L., Schlitzer, R., Slater, R.D., Totterdell, I.J., Weirig, M.F., Yamanaka, Y.,
946
Yool, A., 2005. Anthropogenic ocean acidification over the twenty-first century and its
947
impact on calcifying organisms. Nature 437, 681–686.
948
https://doi.org/10.1038/nature04095.
949
Ou, M., Hamilton, T.J., Eom, J., Lyall, E.M., Gallup, J., Jiang, A., Lee, J., Close, D.A., Yun, S.,
950
Brauner, C.J., 2015. Responses of pink salmon to CO2-induced aquatic acidification. Nat.
951
Clim. Chang. 5, 950–955. https://doi.org/10.1038/NCLIMATE2694.
952
Paula, J.R., Repolho, T., Pegado, M.R., Thörnqvist, P.-O., Bispo, R., Winberg, S., Munday, P.L.,
953
Rosa, R., 2019. Neurobiological and behavioural responses of cleaning mutualisms to
954
ocean warming and acidification. Sci. Rep. 9, 12728. https://doi.org/10.1038/s41598-
955
019-49086-0.
956
Pistevos, J.C.A., Nagelkerken, I., Rossi, T., Connell, S.D., 2017. Antagonistic effects of ocean
957
acidification and warming on hunting sharks. Oikos 126, 241–247.
958
https://doi.org/10.1111/oik.03182.
959
Poortenaar, C.., Hooker, S.., Sharp, N., 2001. Assessment of yellowtail kingfish (Seriola 42
960
lalandi lalandi) reproductive physiology, as a basis for aquaculture development.
961
Aquaculture. 201, 271–286. https://doi.org/10.1016/S0044-8486(01)00549-X.
962
Porteus, C.S., Hubbard, P.C., Uren Webster, T.M., van Aerle, R., Canário, A.V.M., Santos,
963
E.M., Wilson, R.W., 2018. Near-future CO2 levels impair the olfactory system of a
964
marine fish. Nat. Clim. Chang. 8, 737–743. https://doi.org/10.1038/s41558-018-0224-8.
965
Przeslawski, R., Byrne, M., Mellin, C., 2015. A review and meta-analysis of the effects of
966
multiple abiotic stressors on marine embryos and larvae. Glob. Chang. Biol. 21, 2122–
967
2140. https://doi.org/10.1111/gcb.12833.
968
R Core Team, 2017. R: A language and environment for statistical computing. R Foundation
969
for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/.
970
https://doi.org/10.1242/jeb.081984.
971
Roberts, D.D., Stewart, A.L., Struthers, C.D., 2015. The fishes of New Zealand. Volume four
972
systematic account pages 1153-1748. Te Papa Press, Wellington, New Zealand.
973
Rossi, T., Nagelkerken, I., Simpson, S.D., Pistevos, J.C.A., Watson, S.-A., Merillet, L., Fraser,
974
P., Munday, P.L., Connell, S.D., 2015. Ocean acidification boosts larval fish development
975
but reduces the window of opportunity for successful settlement. Proc. R. Soc. B Biol.
976
Sci. 282, 20151954. https://doi.org/10.1098/rspb.2015.1954.
977
Sandersfeld, T., Mark, F.C., Knust, R., 2017. Temperature-dependent metabolism in
978
Antarctic fish: do habitat temperature conditions affect thermal tolerance ranges?
979
Polar Biol. 40, 141–149. https://doi.org/10.1007/s00300-016-1934-x.
980
Schmidt, M., Gerlach, G., Leo, E., Kunz, K.L., Swoboda, S., Pörtner, H.O., Bock, C., Storch, D.,
981
2017. Impact of ocean warming and acidification on the behaviour of two co-occurring
982
gadid species, Boreogadus saida and Gadus morhua, from Svalbard. Mar. Ecol. Prog.
983
Ser. 571, 183–191. https://doi.org/10.3354/meps12130. 43
984
Scott, M., Heupel, M., Tobin, A., Pratchett, M., 2017. A large predatory reef fish species
985
moderates feeding and activity patterns in response to seasonal and latitudinal
986
temperature variation. Sci. Rep. 7, 12966. https://doi.org/10.1038/s41598-017-13277-
987
4.
988
Shears, N.T., Bowen, M.M., 2017. Half a century of coastal temperature records reveal
989
complex warming trends in western boundary currents. Sci. Rep. 7, 14527.
990
https://doi.org/10.1038/s41598-017-14944-2.
991
Sicuro, B., Luzzana, U., 2016. The state of Seriola spp. Other Than Yellowtail (S.
992
quinqueradiata) farming in the world. Rev. Fish. Sci. Aquac. 24, 314–325.
993
https://doi.org/10.1080/23308249.2016.1187583.
994
Silva, C.S.E., Lemos, M.F.L., Faria, A.M., Lopes, A.F., Mendes, S., Gonçalves, E.J., Novais, S.C.,
995
2018. Sand smelt ability to cope and recover from ocean’s elevated CO2 levels.
996
Ecotoxicol. Environ. Saf. 154, 302–310. https://doi.org/10.1016/j.ecoenv.2018.02.011.
997
Sovrano, V.A., Rainoldi, C., Bisazza, A., Vallortigara, G., 1999. Roots of brain specializations:
998
preferential left-eye use during mirror-image inspection in six species of teleost fish.
999
Behav. Brain Res. 106, 175–180. https://doi.org/10.1016/S0166-4328(99)00105-9.
1000
Sswat, M., Stiasny, M.H., Jutfelt, F., Riebesell, U., Clemmesen, C., 2018. Growth performance
1001
and survival of larval Atlantic herring, under the combined effects of elevated
1002
temperatures and CO2. PLoS Biol. 13, e0191947.
1003
https://doi.org/10.1371/journal.pone.0191947.
1004
Sundin, J., Amcoff, M., Mateos-González, F., Raby, G.D., Jutfelt, F., Clark, T.D., 2017. Long-
1005
term exposure to elevated carbon dioxide does not alter activity levels of a coral reef
1006
fish in response to predator chemical cues. Behav. Ecol. Sociobiol. 71.
1007
https://doi.org/10.1007/s00265-017-2337-x. 44
1008
Sundin, J., Jutfelt, F., 2015. 9–28 d of exposure to elevated pCO2 reduces avoidance of
1009
predator odour but had no effect on behavioural lateralization or swimming activity in
1010
a temperate wrasse (Ctenolabrus rupestris). ICES J. Mar. Sci. 73, 620-632.
1011
https://doi.org/10.1093/icesjms/fsv101.
1012
Symonds, J.E., Walker, S.P., Pether, S., Gublin, Y., McQueen, D., King, A., Irvine, G.W.,
1013
Setiawan, A.N., Forsythe, J.A., Bruce, M., 2014. Developing yellowtail kingfish (Seriola
1014
lalandi) and hapuku (Polyprion oxygeneios) for New Zealand aquaculture. New Zeal. J.
1015
Mar. Freshw. Res. 48, 371–384. https://doi.org/10.1080/00288330.2014.930050.
1016
Taylor, R.B., Willis, T.J., 1998. Relationships amongst length, weight and growth of north-
1017
eastern New Zealand reef fishes. Mar. Freshw. Res. 49, 255–260.
1018
https://doi.org/10.1071/MF97016.
1019
Tix, J.A., Hasler, C.T., Sullivan, C., Jeffrey, J.D., Suski, C.D., 2017. Elevated carbon dioxide has
1020
limited acute effects on Lepomis macrochirus behaviour. J. Fish Biol. 90, 751–772.
1021
https://doi.org/10.1111/jfb.13188.
1022
Vossen, L.E., Jutfelt, F., Cocco, A., Thörnqvist, P., Winberg, S., 2016. Zebra fish (Danio rerio)
1023
behaviour is largely unaffected by elevated pCO2. Conserv. Biol. 4, cow065.
1024
https://doi.org/10.1093/conphys/cow065.
1025
Watson, S.-A., Allan, B.J.M., Mcqueen, D.E., Nicol, S., Parsons, D.M., Pether, S.M.J., Pope, S.,
1026
Setiawan, A.N., Smith, N., Wilson, C., Munday, P.L., 2018. Ocean warming has a greater
1027
effect than acidification on the early life history development and swimming
1028
performance of a large circumglobal pelagic fish. Glob. Chang. Biol. 24, 4368-4385.
1029
https://doi.org/10.1111/gcb.14290.
1030 1031
Welch, M.J., Watson, S.-A., Welsh, J.Q., McCormick, M.I., Munday, P.L., 2014. Effects of elevated CO2 on fish behaviour undiminished by transgenerational acclimation. Nat. 45
1032 1033
Clim. Chang. 4, 1086–1089. https://doi.org/10.1038/nclimate2400. Williams, C.R., Dittman, A.H., McElhany, P., Busch, D.S., Maher, M.T., Bammler, T.K.,
1034
MacDonald, J.W., Gallagher, E.P., 2019. Elevated CO2 impairs olfactory-mediated neural
1035
and behavioral responses and gene expression in ocean-phase coho salmon
1036
(Oncorhynchus kisutch). Glob. Chang. Biol. 25, 963–977.
1037
https://doi.org/10.1111/gcb.14532.
1038
Winberg, S., Nilsson, G.E., 1993. Roles of brain monoamine neurotransmitters in agonistic
1039
behaviour and stress reactions, with particular reference to fish. Comp. Biochem.
1040
Physiol. Part C Comp. 106, 597–614. https://doi.org/10.1016/0742-8413(93)90216-8.
1041 1042
Wittmann, A.C., Pörtner, H., 2013. Sensitivities of extant animal taxa to ocean acidification. Nat. Clim. Chang. 3, 995–1001. https://doi.org/10.1038/nclimate1982.
1043 1044
46
Highlights
•
The effects of elevated CO2 on behaviours of kingfish were trait specific.
•
Elevated CO2 increased anxiety in kingfish.
•
Exposure to high temperature in isolation had no significant effect on any trait.
The authors declare no conflicts of interest.
S0141-1136(19)30501-X
DOI:
https://doi.org/10.1016/j.marenvres.2019.104863
Reference:
MERE 104863
To appear in:
Marine Environmental Research
Received Date: 7 August 2019 Revised Date:
12 December 2019
Accepted Date: 14 December 2019
Please cite this article as: Jarrold, M.D., Welch, M.J., McMahon, S.J., McArley, T., Allan, B.J.M., Watson, S.-A., Parsons, D.M., Pether, S.M.J., Pope, S., Nicol, S., Smith, N., Herbert, N., Munday, P.L., Elevated CO2 affects anxiety but not a range of other behaviours in juvenile yellowtail kingfish, Marine Environmental Research (2020), doi: https://doi.org/10.1016/j.marenvres.2019.104863. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2019 Published by Elsevier Ltd.
Michael Jarrold: formal analysis, data curation, writing – original draft, Megan Welch: investigation, writing – review and editing, Shannon McMahon: investigation, writing – review and editing, Tristan McArley, investigation, data curation, formal analysis, writing – review and editing, Bridie Allan: investigation, writing – review and editing, Sue-Ann Watson: investigation, formal analysis, writing – review and editing, Darren M. Parsons: conceptualization, project administration, funding acquisition, writing – review and editing, Stephen Pether: methodology, investigation, project administration, writing – review and editing, Stephen Pope: methodology, investigation, writing – review and editing, Simon Nicol: conceptualization, funding acquisition, writing – review and editing, Neville Smith: conceptualization, funding acquisition, writing – review and editing, Neill Herbert: investigation, project administration, formal analysis, writing – review and editing Philip Munday: conceptualization, investigation, project administration, funding acquisition, supervision, writing – original draft
1
Elevated CO2 affects anxiety but not a range of other behaviours
2
in juvenile yellowtail kingfish
3 4 5
Running head: Elevated CO2 effects on kingfish behaviour
6 7
Michael D. Jarrold1, Megan J. Welch1, Shannon J. McMahon1, Tristan McArley2,
8
Bridie J.M. Allan1,3, Sue-Ann Watson1,4, Darren M. Parsons2,5, Stephen M.J. Pether6,
9
Stephen Pope5, Simon Nicol7, Neville Smith8, Neill Herbert2 & Philip L. Munday1*
10
1
11
University, Townsville, Queensland, 4811, Australia
12
2
13
3
Department of Marine Science, University of Otago, Dunedin 9016, New Zealand
14
4
Biodiversity and Geosciences Program, Museum of Tropical Queensland, Queensland
15
Museum, Townsville, Queensland, 4810, Australia
16
5
National Institute of Water and Atmospheric Research Ltd, Auckland, New Zealand
17
6
National Institute of Water and Atmospheric Research, Northland Marine Research Centre,
18
Station Road, Ruakaka 0116, New Zealand
19
7
Insitute for Applied Ecology, University of Canberra, ACT 2617, Australia
20
8
Oceanic Fisheries Programme, Pacific Community, CPS – B.P. D5 98848, Noumea, New
21
Caledonia
Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook
Leigh Marine Laboratory, The University of Auckland, Leigh 0985, New Zealand
22 23
*Corresponding author email: [email protected]
24 25 1
26
Abstract
27
Elevated seawater CO2 can cause a range of behavioural impairments in marine fishes.
28
However, most studies to date have been conducted on small benthic species and very little
29
is known about how higher oceanic CO2 levels could affect the behaviour of large pelagic
30
species. Here, we tested the effects of elevated CO2, and where possible the interacting
31
effects of high temperature, on a range of ecologically important behaviours (anxiety,
32
routine activity, behavioural lateralization and visual acuity) in juvenile yellowtail kingfish,
33
Seriola lalandi. Kingfish were reared from the egg stage to 25 days post-hatch in a full
34
factorial design of ambient and elevated CO2 (~500 and ~1000 μatm pCO2) and temperature
35
(21 °C and 25 °C). The effects of elevated CO2 were trait-specific with anxiety the only
36
behaviour significantly affected. Juvenile S. lalandi reared at elevated CO2 spent more time
37
in the dark zone during a standard black-white test, which is indicative of increased anxiety.
38
Exposure to high temperature had no significant effect on any of the behaviours tested.
39
Overall, our results suggest that juvenile S. lalandi are largely behaviourally tolerant to
40
future ocean acidification and warming. Given the ecological and economic importance of
41
large pelagic fish species more studies investigating the effect of future climate change are
42
urgently needed.
43 44
Keywords: anxiety, behavioural lateralization, vision, temperature, ocean acidification,
45
climate change, Seriola lalandi
2
46
Introduction
47
Rapidly increasing atmospheric carbon dioxide (CO2) levels are driving a reduction in
48
seawater pH, a process referred to as ‘ocean acidification’ (OA) (Doney et al., 2009; Orr et
49
al., 2005). Recently, atmospheric CO2 levels surpassed 415ppm for the first time in human
50
history (www.esrl.noaa.gov/gmd/ccgg/trends/), and based on the business-as-usual RCP8.5
51
emissions scenario could reach 1000 ppm by the end of the century (Meinshausen et al.,
52
2011). The partial pressure of CO2 (pCO2) at the ocean’s surface is in approximate gas
53
equilibrium with atmospheric CO2 and thus oceanic pCO2 is rising at the same rate as the
54
atmosphere (Doney et al., 2009). However, recent models suggest that seasonal pCO2 cycles
55
in oceans will increase in magnitude throughout the century due to the reduced buffering
56
capacity of acidified seawater (Gallego et al., 2018; Kwiatkowski and Orr, 2018; McNeil and
57
Sasse, 2016). Consequently, surface ocean pCO2 could exceed 1000 μatm for many months
58
each year well before the same average CO2 concentration occurs in the atmosphere
59
(Gallego et al., 2018; Kwiatkowski and Orr, 2018; McNeil and Sasse, 2016). The early life
60
stages of marine organisms are more susceptible to elevated CO2 than older age classes, at
61
least in part because of the relatively high energetic cost of regulating acid base balance
62
when body size is small (Brauner, 2009; Melzner et al., 2009). Indeed, many studies have
63
shown that exposure to elevated CO2 can negatively affect various traits in early life stages
64
across a range of marine taxa (Cattano et al., 2018; Przeslawski et al., 2015; Wittmann and
65
Pörtner, 2013).
66 67
One of the most unexpected impacts of exposure to elevated CO2 to be discovered in
68
marine organisms are effects on sensory systems and ecologically important behaviours
3
69
(Cattano et al., 2018; Clements and Hunt, 2015; Nagelkerken and Munday, 2016). Altered
70
behavioural responses at high CO2 have been observed in a variety of marine taxa, although
71
the majority of work has been conducted on small benthic fishes (Nagelkerken and Munday,
72
2016). For example, over 70 studies have shown that a range of behavioural responses, in
73
both tropical and temperate fish species, are altered under elevated CO2 levels, including
74
but not limited to: predator avoidance/prey detection behaviour, escape responses,
75
activity/anxiety levels, learning ability and lateralization (Cattano et al., 2018; Nagelkerken
76
and Munday, 2016). Behavioural impairments caused by exposure to elevated CO2 have
77
been linked to increased mortality of small juvenile fish in natural settings, inferring that
78
recruitment could be affected by projected future CO2 levels in the ocean (Chivers et al.,
79
2014; Munday et al., 2012, 2010). However, while behavioural impairments at elevated CO2
80
have been observed in a wide range of species, from coral reef fishes to salmon, it is also
81
apparent that not all behaviours are affected, there is interspecific variation in sensitivity,
82
and that some species are much less affected than others (Cattano et al., 2017; Ferrari et al.,
83
2011; Heinrich et al., 2016; Jarrold and Munday, 2018a; Jutfelt and Hedgärde, 2015;
84
Laubenstein et al., 2018; Schmidt et al., 2017; Sundin et al., 2017; Sundin and Jutfelt, 2015).
85 86
Large pelagic fishes perform fundamental ecological roles as the ocean’s top predators.
87
They influence the structure and functioning of marine ecosystems, exerting strong top-
88
down influences on marine food webs (Casini et al., 2009; Frank et al., 2005). Furthermore,
89
they are a critical food source for millions of people in coastal regions worldwide and
90
constitute a large proportion of wild-caught fisheries (FAO, 2016). Despite their high
91
ecological and economic importance, little is known about the potential impacts of ocean
92
acidification on populations of large pelagic fishes owing to the difficulties in rearing and 4
93
closing the life cycles of these species in captivity. It was initially suggested that pelagic fish
94
could be more susceptible to rising levels of ocean pCO2 owing to the relatively stable
95
environmental conditions they experience in open waters (Munday et al., 2008; Nilsson et
96
al., 2012), compared to fish from coastal waters which are subject to highly fluctuating
97
temperature and pH conditions (Hofmann et al., 2011). Nevertheless, the few studies that
98
have tested the effects of end of century projected pCO2 levels on the early life stages of
99
large pelagic fishes have found limited effects on survival, growth and swimming ability
100
(Bignami et al., 2014, 2013; Bromhead et al., 2015; Munday et al., 2016; Watson et al.,
101
2018). Whether or not elevated CO2 causes behavioural impairments in large pelagic fish is
102
largely unknown. To date, only a handful of studies have tested the effects of elevated CO2
103
on behavioural traits in large pelagic fish, with most testing swimming activity and reporting
104
minimal effects (Bignami et al., 2017, 2014; Laubenstein et al., 2018; Munday et al., 2016).
105 106
In addition to ocean acidification, higher concentrations of atmospheric CO2 cause more
107
heat to be retained within the atmosphere, most of which is absorbed by the oceans. For
108
ectothermic animals, such as fishes, temperature dictates metabolic performance and
109
bioenergetics (Enders and Boisclair, 2016; Killen et al., 2010; Sandersfeld et al., 2017). Thus,
110
changes in ambient temperature can affect behaviours, such as foraging and routine activity
111
levels, that are linked to bioenergetics (Allan et al., 2017; Jarrold and Munday, 2018a;
112
Nowicki et al., 2012; Scott et al., 2017; Watson et al., 2018). In some cases, elevated
113
temperature has been shown to have greater overall effects on behavioural responses
114
compared to elevated CO2, especially on behaviours linked to metabolic performance (Allan
115
et al., 2017; Jarrold and Munday, 2018a; Laubenstein et al., 2018; Sswat et al., 2018; Watson
116
et al., 2018). In other cases, significant synergistic and antagonistic interactions between 5
117
elevated CO2 and temperature have been observed (Domenici et al., 2014; Ferrari et al.,
118
2015; Pistevos et al., 2017). Collectively, these studies highlight the importance of studying
119
the combined effects of ocean acidification and ocean warming to accurately predict the
120
behavioural responses of marine fishes to future climate change and the associated
121
ecological consequences.
122 123
The aim of this study was to determine the effects of elevated CO2 and temperature on
124
behavioural responses during the early life history of a large pelagic fish species. To do this,
125
we used the yellowtail kingfish, Seriola lalandi, which has emerged as a potential model
126
species for testing the effects of environmental change on large pelagic fishes (Laubenstein
127
et al., 2018; Munday et al., 2016; Watson et al., 2018), because it is one of the few species
128
that can be reliably reared in captivity (Symonds et al., 2014). The effects of elevated CO2 on
129
behavioural responses of S. lalandi reported to date has been variable. Startle responses of
130
juvenile S. lalandi (18-22 days post hatch (dph)) were impaired by 985 μatm CO2 (Watson et
131
al., 2018), but there was no significant effect of elevated CO2 on activity, startle response
132
and phototaxis at 3 dph (Munday et al., 2016), suggesting that juveniles may be more
133
sensitive to elevated CO2 than very recently hatched larvae. Here, we tested the effects of
134
elevated CO2 on several previously untested behaviours (anxiety, behavioural lateralization
135
and visual acuity) in juvenile S. lalandi (18-25 dph). Preliminary testing using a two-channel
136
flume and a feeding trial found that juvenile kingfish did not respond to the chemical cues of
137
putative predators (juvenile hapuku, Polyprion oxygeneios, and larger juvenile kingfish),
138
therefore it was not possible to test if elevated CO2 affected olfactory response to predator
139
cues, as has been observed in some other fishes (e.g. Ou et al., 2015; Porteus et al., 2018;
140
Williams et al., 2019). Where possible, we also tested the interacting effects of elevated 6
141
temperature on the same behavioural traits. To achieve this, we reared juvenile S. lalandi at
142
current-day ambient CO2 levels (~500 μatm) and average summer temperature for the study
143
location (21°C), crossed with elevated CO2 (~1000 μatm) and temperature (25°C) based on
144
projections for the open ocean by the year 2100 under RCP 8.5 (Collins et al., 2013), and
145
tested behavioural responses using similar methods to previous studies.
146 147
Materials and Methods
148
Study location and species
149
This study focused on the New Zealand population of the yellowtail kingfish, Seriola lalandi,
150
and was conducted at the National Institute of Water and Atmospheric Research (NIWA)
151
Northland Marine Research Centre, Ruakaka, New Zealand. Seriola lalandi is a large coastal
152
pelagic fish with a circumglobal distribution in subtropical waters. In New Zealand waters it
153
reaches up to 1.7 m in length and over 50 kg in weight (McKenzie et al., 2014; Taylor and
154
Willis, 1998). It is a powerful swimmer adapted to a pelagic lifestyle and supports an
155
important recreational and commercial fishery in New Zealand, Australia, Japan and other
156
subtropical regions (McKenzie, 2014; Sicuro and Luzzana, 2016). Kingfish spawn pelagic eggs
157
that hatch within 2-3 days depending on temperature. Flexion in pelagic larvae occurs from
158
about 10 dph and they are metamorphosed juveniles around 20-23 dph (Symonds et al.,
159
2014; Watson et al., 2018). Juveniles have a pelagic lifestyle, often sheltering from large
160
predators under floating debris or weed (Roberts et al., 2015). Juveniles grow rapidly,
161
reaching approximately 0.5 m in length by one year of age in the wild (Stewart et al. 2004).
162 163
Broodstock, eggs and larval culture
7
164
Spawning stocks of S. lalandi were maintained outdoors in 20 m3 circular tanks. Each
165
broodstock tank contained between four and six locally sourced, wild-caught adult fish that
166
had been domesticated in tanks for up to 9 years (approximately equal sex ratio in each tank
167
as occurs in the wild (Poortenaar et al., 2001)). In the current study, experiments were
168
conducted in conjunction with a natural spawning event that occurred on the night of
169
23/01/2017 using eggs collected from four broodstock tanks. Parentage analysis showed
170
that a total of 5 adult females and 10 adult males contributed to the spawning (Munday et
171
al., 2019). Long-term mean summer temperatures for the region are 21°C (Shears and
172
Bowen, 2017), however, local ocean conditions vary naturally and ambient water
173
temperature was 19–20°C in the 5 days immediately prior to spawning and then dropped to
174
18.2°C on the night of spawning. Ambient seawater pHtotal and pCO2 were 7.91 and 589
175
µatm, respectively, in the broodstock tanks. Floating eggs from the four contributing tanks
176
were collected the morning after spawning, mixed, rinsed with oxygenated seawater for 5
177
min, and disinfected with Tosylchloramide (chloramine-T) at 50 ppm for 15 min. Eggs were
178
then rinsed with seawater and distributed into 24 conical 400 L incubation tanks at a density
179
of approximately 100,000 eggs per tank at 12:45h on 24/01/2017. The 400 L incubation
180
tanks were at the nominal CO2 levels and ambient ocean temperature (18.2 °C) at stocking.
181
Heating was turned on at 15:30 h and temperature was allowed to slowly rise to the
182
treatment set points of 21°C and 25°C overnight. Tanks received flow-through seawater at a
183
flow rate of 3 L min-1 with a photoperiod of 14 hours light and 10 hours dark. Eggs hatched
184
two days after stocking at 25°C and three days after stocking at 21°C and larvae were reared
185
for a further 1 day in the incubation tanks before transfer to grow-out tanks.
186
8
187
At 1 dph, larvae were transferred from their rearing tanks into 24 reciprocal grow-out tanks
188
at a density of approximately 45,000 larvae per tank (44,227 ± 2,152 mean ± SD). Grow-out
189
tanks were 1,500 L circular tanks with slightly sloping bottoms with a black internal surface.
190
Each grow-out tank received flow-through seawater at either 21 or 25°C with a photoperiod
191
of 14 hours light and 10 hours dark and at a flow rate of 3 L min-1 and gentle aeration. The
192
flow rates used here are within normal incubation and larvae rearing parameters (3-4 L min-
193
1
194
relatively low density in this trial (250 eggs L-1 c.f. 1,000 eggs L-1 for commercial production).
195
This flow rate also afforded greater margin for maintaining constant temperatures, while
196
providing gentle mixing of eggs and larvae. The overall hatch rates for this trial (76%) was
197
similar or better than those under normal operations (70% in 2019). Larvae were fed with
198
rotifers enriched with S.presso (INVE Aquaculture, Belgium) up to 4 times per day until 14
199
dph, transitioning to S.presso enriched Artemia up to 4 times per day from 11 dph until the
200
end of the experiment at 25dph. Tanks were siphoned daily to remove waste in order to
201
maintain good water quality. Each tank also had a surface skimmer to remove any excess
202
oils from enriched rotifers and Artemia. This study followed animal ethics guidelines at
203
James Cook University (JCU Animal Ethics number: A2357).
, 100-133 mins full turnover rate) for commercial production at NMRC, particularly for the
204 205
Experimental system and water chemistry
206
Seawater pumped from the ocean was filtered through mixed-media, bag filtered to 5 µm,
207
UV light treated to 150 mW.cm-2, heated to 21°C and delivered to large header tanks.
208
Oxygen diffusers in the header tanks maintained baseline minimum dissolved oxygen (100 %
209
saturation) and foam fractionators removed any additional organics. Seawater from each
210
header tank was gravity-fed into eight separate 100 L sump tanks where temperature was 9
211
maintained at ambient control 21°C or elevated to 25°C and CO2 was maintained at ambient
212
control (~500 µatm) or elevated (~1,000 µatm) CO2 in a fully-crossed 2 x 2 experimental
213
design with 2 replicate sumps for each treatment. Seawater from each of the eight
214
treatment sumps was pumped into three of the 400 L incubation tanks during the egg
215
incubation stage and three of the 1,500 L rearing tanks during the grow-out stage, so that
216
there were six replicate experimental tanks at each temperature and CO2 level throughout
217
the experiment.
218 219
Filtered seawater at ambient temperature was heated to 21°C by holding in a 4000L header
220
tank. This water was side streamed through a heat pump (Hot Water Heat Pumps
221
model 7GP35HC-3). This water was delivered to each sump, with each sump having a float
222
valve to maintain a full water level. Water for the 25°C treatment was heated further in the
223
sumps with electronic heaters (2 x Helios 2kW immersion heaters per sump) regulated by
224
Carel IR33 controllers (Carel Industries, Padova, Italy). Temperature was maintained within
225
±0.3°C of the setpoint in all treatments.
226 227
An aquarium pump (Hailea HX-6540) pumped water from each treatment sump to the
228
experimental rearing tanks containing kingfish eggs or larvae. A second aquarium pump
229
(AquaOne Maxi 103) in each sump ensured that the water was well mixed and served as the
230
dosing point for the elevated pCO2 treatments. Elevated pCO2 seawater was achieved by
231
dosing treatment sump tanks with CO2 to the desired pH set point using a pH computer
232
(Aqua Medic, Germany). CO2 was introduced to the pump inlet where it was immediately
233
dissolved by the impeller. A needle valve was used to regulate the flow of CO2 into the
234
powerhead to ensure a slow, steady stream of CO2 into the sump. This slow dosing and 10
235
rapid mixing in the treatment sump tanks ensured that each experimental rearing tank
236
received a steady supply of well-mixed water. All treatment sump tanks, and experimental
237
rearing tanks were housed in environmentally controlled rooms.
238 239
The pHtotal and temperature of each rearing tank were measured daily (SG8 SevenGo Pro,
240
Mettler Toledo, Switzerland). The pH electrode was calibrated with Tris buffers (Scripps
241
Institution of Oceanography, batch number 26). Water samples for total alkalinity (TA)
242
analysis were taken from all rearing tanks at 1, 11 and 21 dph. TA and salinity determination
243
was conducted by the University of Otago Research Centre for Oceanography, Dunedin,
244
New Zealand. Salinity was 35.6 (±0.01) during the experiment. Carbonate chemistry
245
parameters in each tank were calculated in CO2SYS using the measured values of pHtotal,
246
salinity, temperature and TA and the constants K1, K2 from Mehrbach et al. (Mehrbach et
247
al., 1973) refit by Dickson and Millero (Dickson and Millero, 1987), and Dickson et al.
248
(Dickson, 1990) for KHSO4. Seawater carbonate chemistry parameters are shown in Table 1.
249 250
Table 1. Experimental water chemistry. Mean (± S.D.) temperature, salinity, pHtotal, total
251
alkalinity and pCO2 in experiments with yellowtail kingfish (Seriola lalandi) eggs and larvae.
252
Temperature, salinity, pHtotal and total alkalinity were measured directly, pCO2 was
253
estimated from these parameters using CO2SYS. Raw data are available at the Tropical Data
254
Hub; http://doi.org/10.25903/5d54e90e5ce92.
255 Treatment
Treatment
Temperatu Salinity
CO2
temperature
re (°C)
Control
21 °C
21.1 (0.1)
pHtotal
Total alkalinity
pCO2 (µatm)
(µmol.kg-1 SW) 35.6
8.00
11
2318.8 (7.2)
462.0 (42.8)
Control
Elevated
Elevated
25 °C
21 °C
25 °C
24.8 (0.4)
21.1 (0.1)
24.9 (0.4)
(0.1)
(0.03)
35.6
7.94
(0.1)
(0.01)
35.6
7.72
(0.2)
(0.03)
35.6
7.70
(0.1)
(0.01)
2319.9 (7.7)
538.3 (15.6)
2319.0 (3.8)
959.8 (57.3)
2320.0 (6.2)
1010.6 (30.4)
256 257 258
Behavioural trials
259
Behaviours were tested in juvenile S. lalandi between 18-25 dph. The standard length of fish
260
tested ranged from 7.73 ± 1.20mm (mean ± SD) (21°C) to 11.15 ± 2.75mm (25°C) (there was
261
no effect of CO2 treatment on standard length (Watson et al., (2018)). Behavioural trials
262
were conducted at both ambient and elevated CO2 at 21°C and 25°C, except where specified
263
below where only one temperature treatment was tested for each CO2 level. The datasets
264
generated analysed during the current study are available from the corresponding author on
265
request or via the Tropical Research Data Hub (doi: 10.25903/5df17da5f534f).
266
Anxiety and activity trials
267
A light/dark preference (scototaxis) test was used to compare anxiety levels in juvenile S.
268
lalandi among treatments. The light/dark test is a standard method for measuring anxiety-
269
like behaviours in fish and has been validated by pharmacological studies (Maximino et al.,
270
2013, 2011; Mezzomo et al., 2016).In this test, an increase in dark compartment activity
271
(duration and/or entries) reflects increased anxiety, whereas an increase in white
272
compartment activity reflects reduced anxiety. Juvenile kingfish often shelter from large
12
273
predator under floating debris or weed (i.e. dark patches) and so this is an ecologically
274
relevant test for this species. The light/dark arena was a polyethylene tank (measuring 9.5
275
cm wide by 15.5 cm long and 7 cm deep), which had walls lined with black non-reflective
276
tape in one half and white non-reflective tape in the other half, split in the width of the
277
chamber. A barrier (24cm x 22cm x 25.5 cm (LxWxH)) was placed around the arena to
278
eliminate disturbance and to enable the camera (Cannon G15) to be dorsally positioned
279
above the chamber. At the start of each trail the chamber was filled to a depth of 1.5 cm
280
with 200 ml of water from the respective treatment water of the fish being tested, with
281
water being changed between trials. Fish were transferred into the chamber using a small
282
hand net to avoid food entering the testing arena. To standardise for location, fish were
283
placed in the centre of the arena in line with the dark/light divide to avoid an initial
284
preference for the light or dark zone. 72 fish were tested per treatment. Fish were filmed for
285
10.5 min. The first 2 minutes and last 30 seconds of each video were excluded to allow time
286
for the fish to adjust to the arena at the start of the trail and to allow recording error time in
287
manually stopping the camera. A 2 minute acclimation period is consistent with studies that
288
have validated the light/dark test for measuring anxiety in fish (Hamilton et al., 2014;
289
Maximino et al., 2013, 2011; Mezzomo et al., 2016). The amount of time spend in each zone
290
and routine activity in the arena were determined from the trimmed 8-minute video using
291
motion-tracking software (Lolitrack v4.1.0, Loligo Systems, Tjele, Denmark). Anxiety was
292
quantified as the percentage of time spent in the dark zone. We also quantified routine
293
activity as time active (%) and average swimming velocity (cm s-1). All videos were analysed
294
with the observer blind to treatment.
295 296 297 13
298
Behavioural lateralization
299
Lateralization in juvenile S. lalandi was determined using a detour test in a two-way T-maze
300
using methods similar to those described by Welch et al. (2014). The two-way T-maze
301
consisted of an experimental arena (60 x 30 x 20 cm, L x W x H), with a runway in the middle
302
(25 x 3 cm, L x W), and at both ends of the runway (3 cm ahead of the runway) an opaque
303
barrier (12 x 12 x 1 cm) was positioned perpendicular to the runway. The maze was filled to
304
a depth of 2 cm with respective treatment water of the fish being tested. To maintain
305
temperature and dissolved oxygen, the water was changed after each trial. A single fish was
306
placed at one end of the T-maze and given a 2 min habituation period, during which time it
307
could explore the apparatus. This amount of acclimation time is within the range normally
308
reported during lateralization trials, with many reporting significant effects (Hamilton et al.,
309
2017; Jarrold et al., 2017; Lopes et al., 2016; Näslund et al., 2015; Sundin and Jutfelt, 2015).
310
At the end of the habituation period the fish was gently guided into the runway using a flat,
311
black plastic board. This was repeated for a total of 10 runs. 50 fish per treatment were
312
tested. To account for any possible asymmetry in the maze, turns were recorded alternately
313
on the two ends of the runway. Turning preference (i.e. bias in left or right turns) at the
314
population level was assessed using the relative lateralization index (LR, from -100 to +100,
315
indicating complete preference for left and right turning, respectively) according to the
316
formula: LR = [(Turn to the right - Turn to the left) / (Turn to the right + Turn to the left)] *
317
100. The strength of lateralization (irrespective of its direction) was also assessed at the
318
individual-level using the absolute lateralization index LA (ranging from 0 (an individual that
319
turned in equal proportion to the right and to the left) to 100 (an individual that turned right
320
or left on all 10 trials)). Trials were filmed dorsally (Canon G15) and turning direction was
321
scored live with later video validation. The first direction turned when the fish exited the 14
322
runway was recorded. Lateralization trials were only conducted on fish reared at 25 °C as
323
those reared at 21°C were too small for the testing arena.
324 325 326 327 328
Vision
329
visually resolve fine scale detail on a moving background. Visual ability was measured via
330
the presence (or not) of an optomotor response to visual stimuli in a similar fashion to that
331
described by Herbert and Wells, (2002). The optomotor response is an innate behaviour
332
that enables sensory adept animals, including fish, to stabilise their view of and position in
333
the environment.
Changes in visual acuity were assessed by measuring the ability of juvenile S. lalandi to
334 335
The optomotor device consisted of a wooden cabinet with circular holes on the top that
336
provided the frame through which recording cameras and fish holding containers were
337
suspended. Individual juvenile S. lalandi were held in clear 50 mL plastic bottles, suspended
338
on monofilament fishing line 100 mm below a camera housed within a PVC pipe. This setup
339
allowed kingfish to be suspended within a striped rotating drum whilst the camera provided
340
a clear view of kingfish activity. The optomotor device comprised a circular drum (height =
341
215mm, diameter = 250mm) with a patterned paper strip of alternating black and white
342
vertical bars housed atop a motorised spinning plate. Motors were set to spin in a clockwise
343
direction, at a fixed rate of four revolutions min-1. The paper strips had a residual distance
344
(RD, linear distance from midpoint of the bottle to the patterned strips) of 105 mm and six
345
variants of the paper strips (with different bar widths) were used. The width of the black
346
and white bars was calculated to provide a subtended acuity angle of 2°, 3°, 4°, 6°, 8°, and
15
347
10°, assuming fish reacted to the stimulus across the residual distance. A white paper strip
348
with no black bars was used to provide a control condition (0° acuity angle).
349 350
Juvenile S. lalandi were transferred into test bottles containing water at the same CO2 and
351
temperature conditions as their source tank. Only fish reared at 21oC were tested as those
352
reared at 25oC were too fast for the apparatus. Fish were then exposed to all of the
353
patterned strips in turn by manually replacing the patterned strips between tests. At the
354
start of each test sequence, the camera and bottle on the PVC pipe were lowered into a
355
rotating optomotor device, and the fish was allowed to acclimate within stimulus-active
356
conditions for five minutes before data recording was initiated. Fish behaviour was digitally
357
recorded for three minutes, as well as observed in real-time. The behavioural response of
358
each fish was quantified using angular swimming velocity (net revolutions min-1) over a
359
three-minute observation period. Net revolutions min-1, either positive (clockwise) or
360
negative (anti-clockwise) were determined according to:
361
=
−
362 363
where T is the observation period of three minutes. The minimum acuity angle at which
364
optomotor responses were initiated (where revs min-1 first increased significantly from the
365
control 0° behaviour) was defined as the visual acuity threshold. A total of 9 and 8 fish were
366
examined in the ambient and elevated CO2 group respectively.
367 368 369 370
Statistical analysis 16
371
Anxiety trials
372
The effects of CO2 and temperature on percentage time spent in the black zone and
373
percentage time active (proportional data) were initially tested using generalized linear
374
mixed effects models (GLMMs) (family = binomial, link = logit). The effects of CO2 and
375
temperature treatment on velocity (right skewed continuous data) were also initially tested
376
using a GLMM (family = gamma, link = log). In all models CO2 and temperature were fixed
377
factors, standard length was included as a covariate and tank as a random factor. A range of
378
models were tested ranging from fully interactive to fully additive and the best one was
379
chosen based on Akaike information criterion (AIC). In all cases, the fully additive model
380
(Standard length+CO2+Temperature) came out as the best model. However, models were
381
under-dispersed and thus were re-run using a penalised quasi likelihood GLMM.
382 383 384
Behavioural lateralization
385
The effects of elevated CO2 on absolute and relative lateralization were tested using GLMMs
386
(family = binomial, link = logit) with rearing tank included as a random factor. The model for
387
absolute lateralization was weighted to the number of runs (10). The model for absolute
388
laterization was over-dispersed and thus re-run using a penalised quasi likelihood GLMM.
389
Finally, differences in the frequency distribution of relative lateralization scores between
390
ambient and elevated CO2 treatment was tested using a Kolmogorov-Smirnov test.
391 392 393
Vision
17
394
The effect of CO2 treatment on visual acuity was tested using a one-way repeated measures
395
ANOVA. Tank could not be included as a random factor due to the low level of replication in
396
this test.
397 398
Analysis packages
399
The LMM and GLMM analyses were conducted in R version 3.4.0 (R Core Team, 2017) using
400
the ‘lme4’,‘MASS’, ‘nlme’, ‘Car’ and ‘MuMin’ packages. The model outcomes presented
401
were obtained using the Anova function from the ‘Car’ package as opposed to the summary
402
function. This is because Type II testing was required as there were no significant
403
interactions present. The one-way repeated measures ANOVA was conducted in SPSS 25
404
(IBM, Armonk, USA). Please refer to the supplementary material to see all the models tested
405
and their outcomes.
406 407
Results
408
Anxiety trials
409
Percentage time spent in the black zone was significantly affected by CO2 treatment, with
410
fish reared under elevated CO2 spending 15.5% more time in the black zone compared with
411
control fish (Fig 1; χ2 = 3.91, df = 1, P = 0.048, effect size = 0.43 (Cohen’s d)). Temperature
412
treatment had no significant effect on percentage time spent in the black zone (χ2 = 0.37, df
413
= 1, P = 0.542). Finally, standard length had a significant effect on percentage time spent in
414
the black zone (χ2 = 12.21, df = 1, P < 0.001), with larger fish spending more time in the black
415
zone (R2 = 0.15, df = 1,142, P < 0.0001).
416
18
417
Active time ranged from 57.5 ± 3.2% in the ambient CO2 treatment at 21°C to 72.0 ± 3.0% in
418
the ambient CO2 treatment and 25°C (Fig 2A). Active time was not significantly affected by
419
either CO2 (χ2 = 0.039, df = 1, P = 0.844) or temperature (χ2 = 0.24, df = 1, P = 0.624)
420
treatment. Standard length had a significant effect on active time (χ2 = 15.47, df = 1, P <
421
0.0001), with larger fish spending a greater amount of time being active compared with
422
smaller fish (R2 = 0.16, df = 1,142, P < 0.0001).
423 424
Velocity ranged from 0.99 ± 0.05 cm s-1 in the ambient CO2 treatment at 21°C to 1.58 ± 0.16
425
cm s-1 in the ambient CO2 treatments at 25°C (Fig 2B). Velocity was not significantly affected
426
by either CO2 (χ2 = 0.470, df = 1, P = 0.493) or temperature (χ2 = 0.008, df = 1, P = 0.978)
427
treatment. Standard length had a significant effect on velocity (χ2 = 28.94, df = 1, P <
428
0.0001), with larger fish swimming at greater speeds (R2 = 0.25, df = 1,142, P < 0.0001).
429 430
431 19
432 433
Fig. 1. Effects of elevated CO2 and temperature on the percentage of time that juvenile yellowtail
434
kingfish, Seriola lalandi, spent in the black zone during the light/dark test (n = 36 per treatment).
435
Capital letters that differ represent significant differences between CO2 treatments. Bars represent
436
means ± 95% CI.
437 438
439 440 441
Fig. 2. Effects of elevated CO2 and temperature on (A) active time and (B) velocity of juvenile
442
yellowtail kingfish, S. lalandi, during the anxiety trials (n = 36 per treatment). Bars represent means ±
443
95% CI.
444 20
445 446 447 448 449
Behavioural lateralization
450
The S. lalandi used in this experiment were lateralized (mean absolute lateralization (LA) in
451
ambient fish = 44%), however, LA was not significantly different between the ambient and
452
elevated CO2 treatment (Fig 3a; χ2 = 2.96, df = 1, P = 0.085). Similarly, relative lateralization
453
(LR) was not significantly different between the ambient and elevated CO2 treatment (Fig 3b;
454
χ2 = 1.47, df = 1, P = 0.225). LR in the ambient and elevated CO2 treatments were -23.2 ±
455
6.3% and -31.6 ± 7.9% respectively. Finally, the frequency distribution of LR was not
456
significantly different between CO2 treatments (Fig 4; KS = 0.18, P = 0.393).
457 458
Fig 3. Effects of elevated CO2 on: (A) absolute lateralization (LA) and (B) relative lateralization (LR) in
459
juvenile yellowtail kingfish, S. lalandi (n = 50 per treatment) at elevated temperature (25°C).
460
Boxplots are sized according to the 25th and 75th quartiles, where the line identifies the median and
461
the whiskers indicate the minimum and maximum values. + signs represent means.
462 21
463 464
Fig 4. Frequency distributions for relative lateralization (LR) of juvenile S. lalandi at (A) ambient CO2
465
and (B) elevated CO2 at 25°C. Graphs show LR with positive and negative values indicating right and
466
left turns, respectively. The extreme values of -100indicate fish that turned in the same direction for
467
all 10 turns.
468 469 470 471
Vision CO2 treatment had no significant effect on visual acuity (Fig. 5; F = 0.053, df = 1, P = 0.821).
472
There was a significant effect of resolvable angle (Fig. 5; F = 23.96, df = 6, P < 0.001). The
473
number of net revolutions made by juvenile S. lalandi at resolvable angles greater than 6
474
degrees was significantly greater than those observed at angles less than 4 degrees (P <
475
0.05).
476 477
478 22
479 480
Fig 5. Effect of elevated CO2 on the visual acuity of juvenile S. lalandi at 21°C. White and grey points
481
represent ambient and elevated CO2 treatments respectively. Asterisks (*) represent a significant
482
difference from the control (0-degree background) within each of the CO2 treatments. Points
483
represent means ± 95% CI. Points are offset so that error bars can be clearly seen, reading were
484
taken at 0, 2, 3, 4, 6, 8 and 10 degrees.
485 486 487 488 489
Discussion More than 70 studies have shown that elevated CO2 can alter behavioural responses in
490
marine fishes (Munday et al., 2019). However, most studies have been conducted on small
491
benthic species and thus little is known about how predicted future CO2 levels might affect
492
the behaviours of large pelagic species. Even less is known about how elevated CO2 and
493
higher water temperatures may act concurrently on behavioural responses in large pelagic
494
fish. Here, we found that the effects of elevated CO2 on juvenile kingfish, Seriola lalandi,
495
were limited to anxiety. In contrast, elevated temperature had no significant effect on any
496
of the behaviours measured. Overall, our results suggest that juvenile yellowtail kingfish are
497
likely to be largely behaviourally tolerant to future ocean conditions.
498 499
Juvenile S. lalandi exhibited increased anxiety (or reduced boldness) when reared under
500
elevated CO2 conditions, spending a significantly greater proportion of time (+15.5%) in the
501
black zone during a standard light/dark test. Increased anxiety at elevated CO2 has also been
502
observed in Californian rockfish (Sebastes diploproa) using the light/dark test, although the
503
effect size was greater than observed in this study (Cohen’s d = 0.98) (Hamilton et al., 2014).
504
By contrast, another study that used the light/dark test reported no effect of elevated CO2
23
505
on anxiety in Californian blacksmiths (Chromis punctipinnis) (Kwan et al., 2017). Increased
506
anxiety has also been observed in three-spined stickleback (Gasterosteus aculeatus) (Jutfelt
507
et al., 2013) and barramundi (Lates calcarifer) (Rossi et al., 2015), in experimental tests
508
using a novel object and shelter test, respectively. Juvenile kingfish often hide from large
509
predators under floating debris or weed (dark patches). Thus, in a natural setting where
510
food availability is patchy and predators are present, this change in behaviour under
511
elevated CO2 might result in decreased foraging success due to more time spent hiding. This
512
could potentially impact growth and survival trajectories, although in a laboratory setting,
513
where food is available ad libitum, there appears to be limited effects of elevated CO2 on
514
growth and survival of S. lalandi early life stages (Watson et al., 2018). In contrast to anxiety,
515
no significant effect of elevated CO2 on routine activity was observed, which is consistent
516
with past works on the same species (Laubenstein et al., 2018; Munday et al., 2016) and
517
other pelagic species (Bignami et al., 2017, 2014)
518 519
In general, the reported effects of elevated CO2 on fish anxiety and activity are highly
520
variable, yet increased boldness/activity or no effects of elevated CO2 are most often
521
reported (Cattano et al., 2018). While species-specific responses may be partly responsible
522
for the lack of consistency between studies, methodological differences are also likely to be
523
an underlying factor. Indeed, our increased anxiety result contrasts with previous work on
524
the same species where no significant effect of elevated CO2 (1000 μatm) on boldness was
525
reported (Laubenstein et al., 2018). In the present study we used a light/dark test to
526
determine CO2 effects on anxiety, whereas an open field test was used by Laubenstein et al.
527
(2018), both of which are common methods for measuring anxiety in fish (Maximino et al.,
528
2010). Likewise, Hamilton et al. ( 2014) observed increased anxiety in juvenile Californian 24
529
rockfish reared under elevated CO2 (1125 μatm) in a light/dark test, but not in a shelter test.
530
These differing results between established anxiety tests highlight that care should be taken
531
when drawing conclusions about CO2 effects on behaviours, as a null effect could be related
532
to the methodology not being sensitive enough to detect differences as opposed to no
533
effects of elevated CO2. Open field tests with no stimulus, in particular, seem to give
534
extraordinarily variable results and are likely to be an unreliable test of elevated CO2 effects
535
on anxiety/activity (Munday et al., 2019). Future studies, especially those investigating
536
untested species or only one behaviour, should therefore consider using multiple methods
537
to test the same behaviour to more accurately assess behavioural sensitivity to ocean
538
acidification. Alternatively, a diverse range of behavioural responses could be tested.
539 540
In contrast to elevated CO2, high temperature had no effect on anxiety of juvenile S. lalandi,
541
which is consistent with a previous study on the same species (Laubenstein et al., 2018). We
542
also found no significant effect of high temperature on routine activity. This was surprising
543
as routine activity and temperature are often closely correlated, due to effects that
544
temperature has on metabolic rates and energy demands. For example, at high temperature
545
fish may increase their activity to locate more food so that they can offset the increased
546
metabolic costs associated with living at a higher temperatures (Biro et al., 2010).
547
Conversely, if temperatures are too high fish may reduce their activity as an energy-saving
548
strategy (Jarrold and Munday, 2018a; Johansen and Jones, 2011). Laubenstein et al. (2018)
549
documented a 20% increase in resting metabolic rates of juvenile S. lalandi reared at 25°C
550
compared with 21°C, demonstrating a greater cost of living at high temperature, in addition
551
to significantly increased (55%) activity. The reason for contrasting routine activity results
552
between studies is unclear but may be related to the methodological differences described 25
553
above (open field test vs. light/dark test). Indeed, there is a 10% difference in the
554
percentage of time fish were active at 25°C between studies, with Laubenstein et al. (2018)
555
reporting higher activity levels. Considering these two studies used similarly aged fish from
556
the same experiment, this variability may be driven by differences in anxiety related activity
557
between the two experimental setups (open field vs light/dark test). It may be that fish are
558
more anxious in an open field test, with no shelter or dark area, which could lead to
559
hyperactivity (Kysil et al., 2017; Maximino et al., 2010).
560 561
Behavioural lateralization has been linked to higher performance in cognitive tasks, visual
562
assessment, schooling behaviour and escape reactivity in other fish (Bisazza and Dadda,
563
2005; Dadda et al., 2010; Dadda and Bisazza, 2006; Sovrano et al., 1999). We detected no
564
significant effect of elevated CO2 on absolute lateralization (LA). However, there was trend
565
on increased LA at elevated CO2 compared to control conditions (54% vs. 44%). A significant
566
increase in LA was reported in small-spotted catsharks (Scyliorhinus canicula) (Green and
567
Jutfelt, 2014) and zebrafish (Danio rerio) (Vossen et al., 2016) at elevated CO2. However,
568
most studies have reported either decreased (e.g. Jutfelt et al., 2013; Maulvault et al.,
569
2018; Welch et al., 2014) or unchanged (e.g. Hamilton et al., 2017; Silva et al., 2018; Tix et
570
al., 2017) LA under elevated CO2. We also observed no significant effect of elevated CO2 on
571
relative lateralization (LR), although similarly to LA there was a trend of increased LR at
572
elevated CO2 compared to control conditions (-32% vs. -23%). Non-significant effects of
573
elevated CO2 on LR have been reported in a number of other species including blue rockfish,
574
damselfish species and Atlantic cod (Domenici et al., 2012; Hamilton et al., 2017; Jarrold et
575
al., 2017; Jutfelt and Hedgärde, 2015; Schmidt et al., 2017). Unfortunately, we were only
576
able to conduct lateralization trials on fish reared at elevated temperature (25°C) as those 26
577
reared under control temperature (21°C) were too small for the testing arena. Thus, we
578
cannot exclude the possibility that elevated temperature may have affected our observed
579
lateralization results. However, out of the few studies that have tested the combined effects
580
of elevated CO2 and temperature on behavioural lateralization none have reported a
581
significant effect of elevated temperature (in isolation or in combination with CO2) on LA
582
(Domenici et al., 2014; Jarrold and Munday, 2018b; Schmidt et al., 2017) and only one has
583
reported a significant interactive effect between CO2 and temperature on LR (Domenici et
584
al., 2014). Importantly, here we show that the more realistic future conditions of elevated
585
CO2 and temperature in combination had no significant effects on behavioural lateralization
586
in juvenile kingfish.
587 588
Fish rely on visual cues to provide accurate information about risk in both space and time
589
(Ferrari et al., 2010). Therefore, any impairment to the visual system could have important
590
consequences for individual performance. Using an optomotor test, we show that the visual
591
acuity of juvenile S. lalandi was unaffected by elevated CO2. These results contrast with
592
some previous work where negative effects of elevated CO2 on fish vision have been
593
reported. For example, Chung et al. (2014) found that continuous exposure to elevated CO2
594
slowed retinal function in a coral reef damselfish, potentially impairing the capacity of fish
595
to react to fast events. Indeed, experiments have shown that juvenile damselfish exposed to
596
elevated CO2 have reduced visual perception and are slower to react to a predator ambush
597
(Allan et al., 2013; Ferrari et al., 2012). More recently, fish reared in a mesocosm setup at
598
elevated CO2 (910 μatm) showed impaired visual function when the sense was tested in
599
isolation, although this negative effect was not present when fish were tested under a
600
higher level of ecological complexity (Goldenberg et al., 2018). It is possible that the low 27
601
level of replication used here (n = 8-9) could have limited our capacity to detect an effect,
602
although, Chung et al. (2014) used a lower level of replication (n = 5) and still observed
603
significant CO2 effects. It may also be possible that he ability of kingfish to maintain a
604
visually mediated optomotor response under elevated CO2 is linked to preserving fast
605
schooling reactions, a behaviour that is very important for the general success of this
606
species in the pelagic realm. To date, only a few studies have tested visual effects, and this is
607
the first study to use an optomotor test to compare visual acuity between treatments. More
608
studies are needed before any general trends regarding the effect of elevated CO2 on vision
609
can be established.
610 611 612
Here, we report that behavioural responses to elevated CO2 in juvenile S. lalandi are varied,
613
with anxiety the only behaviour to be significantly affected. Similar variability in behavioural
614
responses to elevated CO2 have been observed in other studies (Jarrold and Munday,
615
2018a; Schmidt et al., 2017; Sundin and Jutfelt, 2015). The behavioural changes observed in
616
fish at elevated CO2 appear to be caused by an interference with the GABAA receptor
617
(Nilsson et al., 2012), the primary inhibitory neurotransmitter receptor in the vertebrate
618
brain. The GABAA receptor is an ion-channel with conductance for Cl- and HCO3−. Under
619
elevated CO2, fishes increase intracellular and extracellular HCO3- concentrations, with a
620
corresponding decrease in Cl-, to prevent plasma and tissue acidosis (Baker et al., 2009;
621
Heuer and Grosell, 2014). This altered ion gradient is thought to turn some GABAA receptors
622
from inhibitory to excitatory, ultimately leading to behavioural impairments (Heuer et al.,
623
2016; Heuer and Grosell, 2014). Given the ubiquity of GABAA receptors in animal nervous
624
systems the underlying reason for why some behaviours are affected by elevated CO2 while 28
625
others are not is unclear. While methodological differences may potentially be a factor, it is
626
also possible that there are other physiological mechanisms responsible for causing
627
behavioural alterations in fish at elevated CO2. For example, altered stress hormone levels,
628
such as cortisol and serotonin, are known to directly correlate with activity and anxiety-
629
associated behaviours in fish (Cachat et al., 2010; Egan et al., 2009; Winberg and Nilsson,
630
1993) and a recent study has correlated changes in dopamine and serotonin concentration
631
in the brain with impaired mutualistic interactions in cleaner fishes under elevated CO2
632
(Paula et al., 2019). Alternatively, different sensory systems, and their associated
633
behaviours, may simply have different sensitivities to the altered Cl- and HCO3−
634
concentrations associated with elevated CO2. More studies that investigate the underlying
635
physiological mechanisms behind behavioural sensitivity and tolerance at elevated CO2 are
636
urgently needed. Results from such studies may help to explain why there has been so much
637
behaviour- and species-specific variation in behavioural responses to elevated CO2 observed
638
to date (Cattano et al., 2018).
639 640
In conclusion, the results of this study indicate that juvenile yellowtail kingfish are, in
641
general, behaviourally tolerant to projected near-future CO2 levels as only one behaviour
642
tested was affected. The limited effects of elevated CO2 on behaviours observed here is
643
consistent with past studies on the same species (Laubenstein et al., 2018; Munday et al.,
644
2016). Watson et al. (2018) observed negative effects on escape performance and
645
swimming ability in fish from the same experiment; however, it is important to note that the
646
purely decision/sensory based aspects of the fast starts (latency to react to the stimulus and
647
direction turned) were not affected by elevated CO2. Thus, for juvenile yellowtail kingfish it
648
appears that behaviours that are solely decision/sensory based are less sensitive to elevated 29
649
CO2 compared to those that are more closely linked to metabolic capacity. In general, these
650
results contrast with the expectation that large pelagic fish will be more susceptible to
651
elevated CO2, compared with benthic species, due to the relatively stable environment they
652
live in (Munday et al., 2008; Nilsson et al., 2012). It is possible that the behavioural tolerance
653
of large pelagic fish stems from the fact that they are physiologically adapted to cope with
654
high levels of metabolic CO2 due to their highly active lifestyle. Unfortunately, we were not
655
able to test the effects of high temperature on every behaviour due to logistical issues
656
relating to fish size. However, those behaviours that were tested (anxiety and activity)
657
showed no effects, indicating that juvenile yellowtail kingfish may be behaviourally tolerant
658
to temperature conditions predicted to occur by the year 2100. However, other recent
659
studies on juvenile kingfish have reported significant effects of elevated temperature on
660
some behaviours (routine activity and escape performance) and physiological traits
661
(metabolic rates and critical swimming speeds) (Laubenstein et al., 2018; Watson et al.,
662
2018). Taken together, these recent studies on yellowtail kingfish indicate that this species is
663
likely to be sensitive to future ocean conditions, especially ocean warming. Given the
664
ecological and economic importance of large pelagic fish species more studies investigating
665
the combined effects of elevated CO2 and temperature are urgently needed. Results from
666
such studies will be critical for implementing adaptation and mitigation responses relating
667
to fisheries management.
668 669
Acknowledgments: We thank Michael Exton, Simon Griffiths, David McQueen, Alvin
670
Setiawan, and Carly Wilson for assistance with fish husbandry and maintaining the
671
experiments. We thank Kim Currie and the University of Otago Research Centre for
672
Oceanography for water sample analysis. Finally, we thank Professor Rhondda Jones for 30
673
statistical support. This project was supported by funding from the South Pacific Regional
674
Environment Programme (SPREP) and the Pacific Community (SPC) Pacific Islands Ocean
675
Acidification Partnership (PIOAP). The PIOAP project was funded by the Government of New
676
Zealand and the Principality of Monaco (PIOAP). This project was also supported by funding
677
from the Australian Research Council (FT130100505), the ARC Centre of Excellence for Coral
678
Reef Studies, and NIWA.
679 680
References
681
Allan, B.J.M., Domenici, P., McCormick, M.I., Watson, S.-A., Munday, P.L., 2013. Elevated
682
CO2 affects predator-prey interactions through altered performance. PLoS One 8,
683
e58520. https://doi.org/10.1371/journal.pone.0058520.
684
Allan, B.J.M., Domenici, P., Watson, S.-A., Munday, P.L., McCormick, M.I., 2017. Warming
685
has a greater effect than elevated CO2 on predator–prey interactions in coral reef fish.
686
Proc. R. Soc. B Biol. Sci. 284, 20170784. https://doi.org/10.1098/rspb.2017.0784.
687
Baker, D.W., Matey, V., Huynh, K.T., Wilson, J.M., Morgan, J.D., Brauner, C.J., 2009.
688
Complete intracellular pH protection during extracellular pH depression is associated
689
with hypercarbia tolerance in white sturgeon, Acipenser transmontanus. Am. J. Physiol.
690
Regul. Integr. Comp. Physiol. 296, 1868–1880.
691
https://doi.org/10.1152/ajpregu.90767.2008.
692
Bignami, S., Sponaugle, S., Cowen, R.K., 2014. Effects of ocean acidification on the larvae of
693
a high-value pelagic fisheries species, Mahi-mahi Coryphaena hippurus. Aquat. Biol. 21,
694
249–260. https://doi.org/10.3354/ab00598.
695
Bignami, S., Sponaugle, S., Cowen, R.K., 2013. Response to ocean acidification in larvae of a
31
696
large tropical marine fish, Rachycentron canadum. Glob. Chang. Biol. 19, 996–1006.
697
https://doi.org/10.1111/gcb.12133.
698
Bignami, S., Sponaugle, S., Hauff, M., Cowen, R.K., 2017. Combined effects of elevated pCO2,
699
temperature, and starvation stress on larvae of a large tropical marine fish. ICES J. Mar.
700
Sci. 74, 1220–1229. https://doi.org/10.1093/icesjms/fsw216.
701
Biro, P.A., Beckmann, C., Stamps, J.A., 2010. Small within-day increases in temperature
702
affects boldness and alters personality in coral reef fish. Proc. R. Soc. B Biol. Sci. 277,
703
71–77. https://doi.org/10.1098/rspb.2009.1346.
704 705 706 707
Bisazza, A., Dadda, M., 2005. Enhanced schooling performance in lateralized fishes. Proc. R. Soc. B Biol. Sci. 272, 1677–1681. https://doi.org/10.1098/rspb.2005.3145. Brauner, C.J., 2009. Acid-base balance. In: Finn RN, Kapoor BG (eds) Fish larval physiology. Science Publishers, Enfield, NH, p 185–198. https://doi.org/10.1016/j.tree.2006.11.002
708
Bromhead, D., Scholey, V., Nicol, S., Margulies, D., Wexler, J., Stein, M., Hoyle, S., Lennert-
709
Cody, C., Williamson, J., Havenhand, J., Ilyina, T., Lehodey, P., 2015. The potential
710
impact of ocean acidification upon eggs and larvae of yellowfin tuna (Thunnus
711
albacares). Deep. Res. Part II Top. Stud. Oceanogr. 113, 268–279.
712
https://doi.org/10.1016/j.dsr2.2014.03.019.
713
Cachat, J., Stewart, A., Grossman, L., Gaikwad, S., Kadri, F., Chung, K.M., Wu, N., Wong, K.,
714
Roy, S., Suciu, C., Goodspeed, J., Elegante, M., Bartels, B., Elkhayat, S., Tien, D., Tan, J.,
715
Denmark, A., Gilder, T., Kyzar, E., Dileo, J., Frank, K., Chang, K., Utterback, E., Hart, P.,
716
Kalueff, A. V., 2010. Measuring behavioral and endocrine responses to novelty stress in
717
adult zebrafish. Nat. Protoc. 5, 1786–1799. https://doi.org/10.1038/nprot.2010.140.
718
Casini, M., Hjelm, J., Molinero, J.-C., Lovgren, J., Cardinale, M., Bartolino, V., Belgrano, A.,
719
Kornilovs, G., 2009. Trophic cascades promote threshold-like shifts in pelagic marine 32
720
ecosystems. Proc. Natl. Acad. Sci. USA 106, 197–202.
721
https://doi.org/10.1073/pnas.0806649105.
722
Cattano, C., Calò, A., Di Franco, A., Firmamento, R., Quattrocchi, F., Sdiri, K., Guidetti, P.,
723
Milazzo, M., 2017. Ocean acidification does not impair predator recognition but
724
increases juvenile growth in a temperate wrasse off CO2 seeps. Mar. Environ. Res. 132,
725
33–40. https://doi.org/10.1016/j.marenvres.2017.10.013.
726
Cattano, C., Claudet, J., Domenici, P., Milazzo, M., 2018. Living in a high CO2 world: a global
727
meta-analysis shows multiple trait-mediated responses of fish to ocean acidification.
728
Ecol. Monogr. 88, 320-335. https://doi.org/10.1002/ecm.1297.
729
Chivers, D.P., McCormick, M.I., Nilsson, G.E., Munday, P.L., Watson, S.-A., Meekan, M.G.,
730
Mitchell, M.D., Corkill, K.C., Ferrari, M.C.O., 2014. Impaired learning of predators and
731
lower prey survival under elevated CO2 : a consequence of neurotransmitter
732
interference. Glob. Chang. Biol. 20, 515–522. https://doi.org/10.1111/gcb.12291.
733
Chung, W.-S., Marshall, N.J., Watson, S.-A., Munday, P.L., Nilsson, G.E., 2014. Ocean
734
acidification slows retinal function in a damselfish through interference with GABAA
735
receptors. J. Exp. Biol. 217, 323–326. https://doi.org/10.1242/jeb.092478.
736
Clements, J.C., Hunt, H.L., 2015. Marine animal behaviour in a high CO2 ocean Marine animal
737
behaviour in a high CO 2 ocean. Mar. Ecol. Prog. Ser. 536, 259–279.
738
https://doi.org/10.3354/meps11426.
739
Collins, M., Knutti, R., Arblaster, J., Dufresne, J.-L., Fichefet, T., Friedlingstein, P., Gao, X.,
740
Gutowski, W.J., Johns, T., Krinner, G., Shongwe, M., Tebaldi, C., Weaver, A.J.,
741
Wehner, M., 2013. Long-term Climate Change: Projections, Commitments and
742
Irreversibility. In T. F. Stocker, D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J.
743
Boschung, A. Nauels, Y. Xia, V. Bex, & P. M. Midgley (Eds.), Climate change 2013: 33
744
The physical science basis. contribution of working group i to the fifth assessment
745
report of the intergovernmental panel on climate change (pp. 1029–1136). Cambridge,
746
UK and New York, NY: Cambridge University Press.
747
Dadda, M., Bisazza, A., 2006. Lateralized female topminnows can forage and attend to a
748
harassing male simultaneously. Behav. Ecol. 17, 358–363.
749
https://doi.org/10.1093/beheco/arj040.
750
Dadda, M., Koolhaas, W.H., Domenici, P., 2010. Behavioural asymmetry affects escape
751
performance in a teleost fish. Biol. Lett. 6, 414–417.
752
https://doi.org/10.1098/rsbl.2009.0904.
753
Dickson, A.G., 1990. Standard potential of the reaction: AgCl(s) + 1/2H2(g) = Ag(s) + HCl(aq),
754
and and the standard acidity constant of the ion HSO4− in synthetic sea water from
755
273.15 to 318.15 K. J. Chem. Thermodyn. 22, 113–127. https://doi.org/10.1016/0021-
756
9614(90)90074-Z.
757
Dickson, A.G., Millero, F.J., 1987. A comparison of the equilibrium constants for the
758
dissociation of carbonic acid in seawater media. Deep Sea Res. Part A. Oceanogr. Res.
759
Pap. 34, 1733–1743. https://doi.org/10.1016/0198-0149(87)90021-5.
760
Domenici, P., Allan, B., McCormick, M.I., Munday, P.L., 2012. Elevated carbon dioxide affects
761
behavioural lateralization in a coral reef fish. Biol. Lett. 8, 78–81.
762
https://doi.org/10.1098/rsbl.2011.0591.
763
Domenici, P., Allan, B.J.M., Watson, S.-A., McCormick, M.I., Munday, P.L., 2014. Shifting
764
from right to left: the combined effect of elevated CO2 and temperature on behavioural
765
lateralization in a coral reef fish. PLoS One 9, e87969.
766
https://doi.org/10.1371/journal.pone.0087969,
767
Doney, S.C., Fabry, V.J., Feely, R.A., Kleypas, J.A., 2009. Ocean Acidification: the other CO2 34
768
Problem. Ann. Rev. Mar. Sci. 1, 169–192.
769
https://doi.org/10.1146/annurev.marine.010908.163834.
770
Egan, R.J., Bergner, C.L., Hart, P.C., Cachat, J.M., Canavello, P.R., Elegante, M.F., Elkhayat,
771
S.I., Bartels, B.K., Tien, A.K., Tien, D.H., Mohnot, S., Beeson, E., Glasgow, E., Amri, H.,
772
Zukowska, Z., Kalueff, A. V., 2009. Understanding behavioral and physiological
773
phenotypes of stress and anxiety in zebrafish. Behav. Brain Res. 205, 38–44.
774
https://doi.org/10.1016/j.bbr.2009.06.022.
775
Enders, E.C., Boisclair, D., 2016. Effects of environmental fluctuations on fish metabolism:
776
Atlantic salmon Salmo salar as a case study. J. Fish Biol. 88, 344–358.
777
https://doi.org/10.1111/jfb.12786.
778 779 780
FAO. The State of World Fisheries and Aquaculture. Contributing to food security and nutrition for all; FAO: Rome, Italy, 2016. Ferrari, M.C.O., Dixson, D.L., Munday, P.L., Mccormick, M.I., Meekan, M.G., Sih, A., Chivers,
781
D.P., 2011. Intrageneric variation in antipredator responses of coral reef fishes affected
782
by ocean acidification: implications for climate change projections on marine
783
communities. Glob. Chang. Biol. 17, 2980–2986. https://doi.org/10.1111/j.1365-
784
2486.2011.02439.x.
785
Ferrari, M.C.O., McCormick, M.I., Munday, P.L., Meekan, M.G., Dixson, D.L., Lönnstedt, O.,
786
Chivers, D.P., 2012. Effects of ocean acidification on visual risk assessment in coral reef
787
fishes. Funct. Ecol. 26, 553–558. https://doi.org/10.1111/j.1365-2435.2011.01951.x.
788
Ferrari, M.C.O., Munday, P.L., Rummer, J.L., McCormick, M.I., Corkill, K., Watson, S.-A., Allan,
789
B.J.M., Meekan, M.G., Chivers, D.P., 2015. Interactive effects of ocean acidification and
790
rising sea temperatures alter predation rate and predator selectivity in reef fish
791
communities. Glob. Chang. Biol. 21, 1848–1855. https://doi.org/10.1111/gcb.12818. 35
792
Ferrari, M.C.O., Wisenden, B.D., Chivers, D.P., 2010. Chemical ecology of predator – prey
793
interactions in aquatic ecosystems: a review and prospectus. Canadain J. Zool. 724,
794
698–724. https://doi.org/10.1139/Z10-029.
795
Frank, K.T., Petrie, B., Choi, J.S., Leggett, W.C., 2005. Trophic cascades in a formerly cod-
796
dominated ecosystem. Science. 308, 1621–1623.
797
https://doi.org/10.1126/science.1113075.
798
Gallego, M.A., Timmermann, A., Friedrich, T., Zeebe, R.E., 2018. Drivers of future seasonal
799
cycle changes of oceanic pCO2. Biogeosciences 15, 5315–5327.
800
https://doi.org/10.5194/bg-2018-212.
801
Goldenberg, S.U., Nagelkerken, I., Marangon, E., Bonnet, A., Ferreira, C.M., Connell, S.D.,
802
2018. Ecological complexity buffers the impacts of future climate on marine
803
consumers. Nat. Clim. Chang. 8, 229–233. https://doi.org/10.1038/s41558-018-0086-0.
804
Green, L., Jutfelt, F., 2014. Elevated carbon dioxide alters the plasma composition and
805
behaviour of a shark. Biol. Lett. 10, 20140538. https://doi.org/10.1098/rsbl.2014.0538.
806
Hamilton, S.L., Logan, C.A., Fennie, H.W., Sogard, S.M., Barry, J.P., Makukhov, A.D., Tobosa,
807
L.R., Boyer, K., Lovera, C.F., Bernardi, G., 2017. Species-specific responses of juvenile
808
rockfish to elevated pCO2: from behavior to genomics. PLoS One 12, e0169670.
809
https://doi.org/10.1371/journal. pone.0169670.
810
Hamilton, T.J., Holcombe, A., Tresguerres, M., 2014. CO2-induced ocean acidification
811
increases anxiety in Rockfish via alteration of GABAA receptor functioning. Proc. R. Soc.
812
281, 20132509. https://doi.org/10.1098/rspb.2013.2509.
813
Heinrich, D.D.U., Watson, S.-A., Rummer, J.L., Brandl, S.J., Simpfendorfer, C.A., Heupel, M.R.,
814
Munday, P.L., 2016. Foraging behaviour of the epaulette shark Hemiscyllium ocellatum
815
is not affected by elevated CO2. ICES J. Mar. Sci. 73, 633–640. 36
816 817
https://doi.org/10.1093/icesjms/fss153. Herbert, N.A., Wells, R.M.G., 2002. The effect of strenuous exercise and β-adrenergic
818
blockade on the visual performance of juvenile rainbow trout, Oncorhynchus mykiss. J.
819
Comp. Physiol. B Biochem. Syst. Environ. Physiol. 172, 725–731.
820
https://doi.org/10.1007/s00360-002-0303-y.
821
Heuer, R.M., Grosell, M., 2014. Physiological impacts of elevated carbon dioxide and ocean
822
acidification on fish. Am. J. Physiol. Regul. Integr. Comp. Physiol. 307, R1061–R1084.
823
https://doi.org/10.1152/ajpregu.00064.2014.
824
Heuer, R.M., Welch, M.J., Rummer, J.L., Munday, P.L., Grosell, M., 2016. Altered brain ion
825
gradients following compensation for elevated CO2 are linked to behavioural
826
alterations in a coral reef fish. Sci. Rep. 6, 33216. https://doi.org/10.1038/srep33216.
827
Hofmann, G.E., Smith, J.E., Johnson, K.S., Send, U., Levin, L.A., Paytan, A., Price, N.N.,
828
Peterson, B., Takeshita, Y., Matson, P.G., Crook, E.D., Kroeker, K.J., Gambi, M.C., Rivest,
829
E.B., Frieder, C.A., Yu, P.C., Martz, T.R., 2011. High-frequency dynamics of ocean pH: a
830
multi-ecosystem comparison. PLoS One 6, e28983.
831
https://doi.org/10.1371/journal.pone.0028983.
832
Jarrold, M.D., Humphrey, C., McCormick, M.I., Munday, P.L., 2017. Diel CO2 cycles reduce
833
severity of behavioural abnormalities in coral reef fish under ocean acidification. Sci.
834
Rep. 7, 10153. https://doi.org/10.1038/s41598-017-10378-y.
835
Jarrold, M.D., Munday, P.L., 2018a. Elevated temperature does not substantially modify the
836
interactive effects between elevated CO2 and diel CO2 cycles on the survival, growth
837
and behavior of a coral reef fish. Front. Mar. Sci. 5, 458. doi:
838
10.3389/fmars.2018.00458. https://doi.org/10.3389/fmars.2018.00458.
839
Johansen, J.L., Jones, G.P., 2011. Increasing ocean temperature reduces the metabolic 37
840
performance and swimming ability of coral reef damselfishes. Glob. Chang. Biol. 17,
841
2971–2979. https://doi.org/10.1111/j.1365-2486.2011.02436.x.
842
Jutfelt, F., Bresolin de Souza, K., Vuylsteke, A., Sturve, J., 2013. Behavioural disturbances in a
843
temperate fish exposed to sustained high-CO2 Levels. PLoS One 8, e65825.
844
https://doi.org/10.1371/journal.pone.0065825.
845
Jutfelt, F., Hedgärde, M., 2015. Juvenile Atlantic cod behavior appears robust to near-future
846
CO2 levels. Front. Zool. 12, 11. doi: https://doi.org/10.1186/s12983-015-0104-2.
847
Killen, S.S., Atkinson, D., Glazier, D.S., 2010. The intraspecific scaling of metabolic rate with
848
body mass in fishes depends on lifestyle and temperature. Ecol. Lett. 13, 184–193.
849
https://doi.org/10.1111/j.1461-0248.2009.01415.x.
850
Kwan, G.T., Hamilton, T.J., Tresguerres, M., 2017. CO2-induced ocean acidification does not
851
affect individual or group behaviour in a temperate damselfish. R. Soc. Open Sci. 4,
852
170283. https://doi.org/10.1098/rsos.170283.
853
Kwiatkowski, L., Orr, J.C., 2018. Diverging seasonal extremes for ocean acidification during
854
the twenty-first century. Nat. Clim. Chang. 8, 141–145.
855
https://doi.org/10.1038/s41558-017-0054-0.
856
Kysil, E. V., Meshalkina, D.A., Frick, E.E., Echevarria, D.J., Rosemberg, D.B., Maximino, C.,
857
Lima, M.G., Abreu, M.S., Giacomini, A.C., Barcellos, L.J.G., Song, C., Kalueff, A. V., 2017.
858
Comparative analyses of zebrafish anxiety-like behavior using conflict-based novelty
859
tests. Zebrafish 14, 197–208. https://doi.org/10.1089/zeb.2016.1415.
860
Laubenstein, T., Rummer, J., Nicol, S., Parsons, D., Pether, S., Pope, S., Smith, N., Munday, P.,
861
2018. Correlated effects of ocean acidification and warming on behavioral and
862
metabolic traits of a large pelagic fish. Diversity 10, 35.
863
https://doi.org/10.3390/d10020035. 38
864
Lopes, A.F., Morais, P., Pimentel, M., Rosa, R., Munday, P.L., Goncalves, E.J., Faria, A.M.,
865
2016. Behavioural lateralization and shoaling cohesion of fish larvae altered under
866
ocean acidification. Mar. Biol. 163, 243. https://doi.org/10.1007/s00227-016-3026-4.
867
Maulvault, A.L., Santos, L.H.M.L.M., Paula, J.R., Camacho, C., Pissarra, V., Fogaça, F.,
868
Barbosa, V., Alves, R., Ferreira, P.P., Barceló, D., Rodriguez-Mozaz, S., Marques, A.,
869
Diniz, M., Rosa, R., 2018. Differential behavioural responses to venlafaxine exposure
870
route, warming and acidification in juvenile fish (Argyrosomus regius). Sci. Total
871
Environ. 634, 1136–1147. https://doi.org/10.1016/j.scitotenv.2018.04.015.
872
Maximino, C., da Silva, A.W.B., Gouveia, A., Herculano, A.M., 2011. Pharmacological analysis
873
of zebrafish (Danio rerio) scototaxis. Prog. Neuro-Psychopharmacology Biol. Psychiatry
874
35, 624–631. https://doi.org/10.1016/j.pnpbp.2011.01.006.
875
Maximino, C., de Brito, T.M., da Silva Batista, A.W., Herculano, A.M., Morato, S., Gouveia, A.,
876
2010. Measuring anxiety in zebrafish: a critical review. Behav. Brain Res. 214, 157–171.
877
https://doi.org/10.1016/j.bbr.2010.05.031.
878
Maximino, C., Puty, B., Benzecry, R., Araújo, J., Lima, M.G., De Jesus Oliveira Batista, E.,
879
Renata De Matos Oliveira, K., Crespo-Lopez, M.E., Herculano, A.M., 2013. Role of
880
serotonin in zebrafish (Danio rerio) anxiety: relationship with serotonin levels and
881
effect of buspirone, WAY 100635, SB 224289, fluoxetine and para-chlorophenylalanine
882
(pCPA) in two behavioral models. Neuropharmacology 71, 83–97.
883
https://doi.org/10.1016/j.neuropharm.2013.03.006.
884
McKenzie, J.R., 2014. Review of productivity parameters and stock assessment options for
885
kingfish (Seriola lalandi lalandi). New Zealand Fisheries Assessment Report 2014/04.
886
Ministry for Primary Industries, Wellington, New Zealand.
887
McKenzie, J.R., Smith, M., Watson, T., Francis, M., Ó Maolagáin, C., Poortenaar, C., 39
888
Holdsworth, J., 2014. Age, growth, maturity and natural mortality of New Zealand
889
kingfish (Seriola lalandi lalandi). Wellington, New Zealand: Ministry for Primary
890
Industries.
891
McNeil, B.I., Sasse, T.P., 2016. Future ocean hypercapnia driven by anthropogenic
892
amplification of the natural CO2 cycle. Nature 529, 383–386.
893
https://doi.org/10.1038/nature16156.
894
Mehrbach, C., Culberson, C.H., Hawley, J.E., Pytkowicz, R.M., 1973. Measurement of the
895
apparent dissociation constants of carbonic acid in seawater at atmospheric pressure.
896
Limnol. Oceanogr. 18, 897–907. https://doi.org/10.4319/lo.1973.18.6.0897.
897
Meinshausen, M., Smith, S.J., Calvin, K., Daniel, J.S., Kainuma, M.L.T., 2011. The RCP
898
greenhouse gas concentrations and their extensions from 1765 to 2300. Clim. Change
899
109, 213–241. https://doi.org/10.1007/s10584-011-0156-z.
900
Melzner, F., Gutowska, M.A., Langenbuch, M., Dupont, S., Lucassen, M., Thorndyke, M.C.,
901
Bleich, M., Portner, H.-O., 2009. Physiological basis for high CO2 tolerance in marine
902
ectothermic animals: pre-adaptation through lifestyle and ontogeny? Biogeosciences 6,
903
2313–2331. https://doi.org/10.5194/bg-6-2313-2009.
904
Mezzomo, N.J., Silveira, A., Giuliani, G.S., Quadros, V.A., Rosemberg, D.B., 2016. The role of
905
taurine on anxiety-like behaviors in zebrafish: a comparative study using the novel tank
906
and the light-dark tasks. Neurosci. Lett. 613, 19–24.
907
https://doi.org/10.1016/j.neulet.2015.12.037.
908
Munday, P.L., Dixson, D.L., McCormick, M.I., Meekan, M., Ferrari, M.C.O., Chivers, D.P.,
909
2010. Replenishment of fish populations is threatened by ocean acidification. Proc.
910
Natl. Acad. Sci. USA. 107, 12930–12934. https://doi.org/10.1073/pnas.1004519107.
911
Munday, Philip L, Jarrold, M.D., Nagelkerken, I., 2019. Ecological effects of elevated CO2 on 40
912
marine and freshwater fishes: from individual to community effects, Fish physiology
913
Carbon dioxide Vol 37 (Eds Grosell. M, Munday. P, Farrell. A and Brauner. C). Elseiver,
914
Amsterdam.
915
Munday, P.L., Jones, G.P., Pratchett, M.S., Williams, A.J., 2008. Climate change and the
916
future for coral reef fishes. Fish and Fish. 9, 261–285. https://doi.org/10.1111/j.1467-
917
2979.2008.00281.x.
918
Munday, P.L., McCormick, M.I., Meekan, M., Dixson, D.L., Watson, S.-A., Chivers, D.P.,
919
Ferrari, M.C.O., 2012. Selective mortality associated with variation in CO2 tolerance in a
920
marine fish. Ocean Acidif. 1, 1–5. https://doi.org/10.2478/oac-2012-0001.
921
Munday, Phillip L., Schunter, C., Allan, B.J.M., Nicol, S., Parsons, D.M., Pether, S.M.J., Pope,
922
S., Ravasi, T., Setiawan, A.N., Smith, N., Domingos, J.A., 2019. Testing the adaptive
923
potential of yellowtail kingfish to ocean warming and acidification. Front. Ecol. Evol. 7,
924
253. https://doi: 10.3389/fevo.2019.00253.
925
Munday, P.L., Watson, S.-A., Parsons, D.M., King, A., Barr, N.G., McLeod, I.M., Allan, B.J.M.,
926
Pether, S.M.J., 2016. Effects of elevated CO2 on early life history development of the
927
yellowtail kingfish, Seriola lalandi, a large pelagic fish. ICES J. Mar. Sci. 73, 641–649.
928
https://doi.org/10.1093/icesjms/fsv210.
929
Nagelkerken, I., Munday, P.L., 2016. Animal behaviour shapes the ecological effects of ocean
930
acidification and warming : moving from individual to community-level responses.
931
Glob. Chang. Biol. 22, 974–989. https://doi.org/10.1111/gcb.13167.
932
Näslund, J., Lindström, E., Lai, F., Jutfelt, F., 2015. Behavioural responses to simulated bird
933
attacks in marine three-spined sticklebacks after exposure to high CO2 levels. Mar
934
Freshwater Res. 66, 877–885. https://doi.org/10.1071/MF14144.
935
Nilsson, G.E., Dixson, D.L., Domenici, P., McCormick, M.I., Sørensen, C., Watson, S.-A., 41
936
Munday, P.L., 2012. Near-future carbon dioxide levels alter fish behaviour by
937
interfering with neurotransmitter function. Nat. Clim. Chang. 2, 201–204.
938
https://doi.org/10.1038/nclimate1352.
939
Nowicki, J.P., Miller, G.M., Munday, P.L., 2012. Interactive effects of elevated temperature
940
and CO2 on foraging behavior of juvenile coral reef fish. J. Exp. Mar. Bio. Ecol. 412, 46–
941
51. https://doi.org/10.1016/j.jembe.2011.10.020.
942
Orr, J.C., Fabry, V.J., Aumont, O., Bopp, L., Doney, S.C., Feely, R.A., Gnanadesikan, A.,
943
Gruber, N., Ishida, A., Joos, F., Key, R.M., Lindsay, K., Maier-Reimer, E., Matear, R.,
944
Monfray, P., Mouchet, A., Najjar, R.G., Plattner, G.K., Rodgers, K.B., Sabine, C.L.,
945
Sarmiento, J.L., Schlitzer, R., Slater, R.D., Totterdell, I.J., Weirig, M.F., Yamanaka, Y.,
946
Yool, A., 2005. Anthropogenic ocean acidification over the twenty-first century and its
947
impact on calcifying organisms. Nature 437, 681–686.
948
https://doi.org/10.1038/nature04095.
949
Ou, M., Hamilton, T.J., Eom, J., Lyall, E.M., Gallup, J., Jiang, A., Lee, J., Close, D.A., Yun, S.,
950
Brauner, C.J., 2015. Responses of pink salmon to CO2-induced aquatic acidification. Nat.
951
Clim. Chang. 5, 950–955. https://doi.org/10.1038/NCLIMATE2694.
952
Paula, J.R., Repolho, T., Pegado, M.R., Thörnqvist, P.-O., Bispo, R., Winberg, S., Munday, P.L.,
953
Rosa, R., 2019. Neurobiological and behavioural responses of cleaning mutualisms to
954
ocean warming and acidification. Sci. Rep. 9, 12728. https://doi.org/10.1038/s41598-
955
019-49086-0.
956
Pistevos, J.C.A., Nagelkerken, I., Rossi, T., Connell, S.D., 2017. Antagonistic effects of ocean
957
acidification and warming on hunting sharks. Oikos 126, 241–247.
958
https://doi.org/10.1111/oik.03182.
959
Poortenaar, C.., Hooker, S.., Sharp, N., 2001. Assessment of yellowtail kingfish (Seriola 42
960
lalandi lalandi) reproductive physiology, as a basis for aquaculture development.
961
Aquaculture. 201, 271–286. https://doi.org/10.1016/S0044-8486(01)00549-X.
962
Porteus, C.S., Hubbard, P.C., Uren Webster, T.M., van Aerle, R., Canário, A.V.M., Santos,
963
E.M., Wilson, R.W., 2018. Near-future CO2 levels impair the olfactory system of a
964
marine fish. Nat. Clim. Chang. 8, 737–743. https://doi.org/10.1038/s41558-018-0224-8.
965
Przeslawski, R., Byrne, M., Mellin, C., 2015. A review and meta-analysis of the effects of
966
multiple abiotic stressors on marine embryos and larvae. Glob. Chang. Biol. 21, 2122–
967
2140. https://doi.org/10.1111/gcb.12833.
968
R Core Team, 2017. R: A language and environment for statistical computing. R Foundation
969
for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/.
970
https://doi.org/10.1242/jeb.081984.
971
Roberts, D.D., Stewart, A.L., Struthers, C.D., 2015. The fishes of New Zealand. Volume four
972
systematic account pages 1153-1748. Te Papa Press, Wellington, New Zealand.
973
Rossi, T., Nagelkerken, I., Simpson, S.D., Pistevos, J.C.A., Watson, S.-A., Merillet, L., Fraser,
974
P., Munday, P.L., Connell, S.D., 2015. Ocean acidification boosts larval fish development
975
but reduces the window of opportunity for successful settlement. Proc. R. Soc. B Biol.
976
Sci. 282, 20151954. https://doi.org/10.1098/rspb.2015.1954.
977
Sandersfeld, T., Mark, F.C., Knust, R., 2017. Temperature-dependent metabolism in
978
Antarctic fish: do habitat temperature conditions affect thermal tolerance ranges?
979
Polar Biol. 40, 141–149. https://doi.org/10.1007/s00300-016-1934-x.
980
Schmidt, M., Gerlach, G., Leo, E., Kunz, K.L., Swoboda, S., Pörtner, H.O., Bock, C., Storch, D.,
981
2017. Impact of ocean warming and acidification on the behaviour of two co-occurring
982
gadid species, Boreogadus saida and Gadus morhua, from Svalbard. Mar. Ecol. Prog.
983
Ser. 571, 183–191. https://doi.org/10.3354/meps12130. 43
984
Scott, M., Heupel, M., Tobin, A., Pratchett, M., 2017. A large predatory reef fish species
985
moderates feeding and activity patterns in response to seasonal and latitudinal
986
temperature variation. Sci. Rep. 7, 12966. https://doi.org/10.1038/s41598-017-13277-
987
4.
988
Shears, N.T., Bowen, M.M., 2017. Half a century of coastal temperature records reveal
989
complex warming trends in western boundary currents. Sci. Rep. 7, 14527.
990
https://doi.org/10.1038/s41598-017-14944-2.
991
Sicuro, B., Luzzana, U., 2016. The state of Seriola spp. Other Than Yellowtail (S.
992
quinqueradiata) farming in the world. Rev. Fish. Sci. Aquac. 24, 314–325.
993
https://doi.org/10.1080/23308249.2016.1187583.
994
Silva, C.S.E., Lemos, M.F.L., Faria, A.M., Lopes, A.F., Mendes, S., Gonçalves, E.J., Novais, S.C.,
995
2018. Sand smelt ability to cope and recover from ocean’s elevated CO2 levels.
996
Ecotoxicol. Environ. Saf. 154, 302–310. https://doi.org/10.1016/j.ecoenv.2018.02.011.
997
Sovrano, V.A., Rainoldi, C., Bisazza, A., Vallortigara, G., 1999. Roots of brain specializations:
998
preferential left-eye use during mirror-image inspection in six species of teleost fish.
999
Behav. Brain Res. 106, 175–180. https://doi.org/10.1016/S0166-4328(99)00105-9.
1000
Sswat, M., Stiasny, M.H., Jutfelt, F., Riebesell, U., Clemmesen, C., 2018. Growth performance
1001
and survival of larval Atlantic herring, under the combined effects of elevated
1002
temperatures and CO2. PLoS Biol. 13, e0191947.
1003
https://doi.org/10.1371/journal.pone.0191947.
1004
Sundin, J., Amcoff, M., Mateos-González, F., Raby, G.D., Jutfelt, F., Clark, T.D., 2017. Long-
1005
term exposure to elevated carbon dioxide does not alter activity levels of a coral reef
1006
fish in response to predator chemical cues. Behav. Ecol. Sociobiol. 71.
1007
https://doi.org/10.1007/s00265-017-2337-x. 44
1008
Sundin, J., Jutfelt, F., 2015. 9–28 d of exposure to elevated pCO2 reduces avoidance of
1009
predator odour but had no effect on behavioural lateralization or swimming activity in
1010
a temperate wrasse (Ctenolabrus rupestris). ICES J. Mar. Sci. 73, 620-632.
1011
https://doi.org/10.1093/icesjms/fsv101.
1012
Symonds, J.E., Walker, S.P., Pether, S., Gublin, Y., McQueen, D., King, A., Irvine, G.W.,
1013
Setiawan, A.N., Forsythe, J.A., Bruce, M., 2014. Developing yellowtail kingfish (Seriola
1014
lalandi) and hapuku (Polyprion oxygeneios) for New Zealand aquaculture. New Zeal. J.
1015
Mar. Freshw. Res. 48, 371–384. https://doi.org/10.1080/00288330.2014.930050.
1016
Taylor, R.B., Willis, T.J., 1998. Relationships amongst length, weight and growth of north-
1017
eastern New Zealand reef fishes. Mar. Freshw. Res. 49, 255–260.
1018
https://doi.org/10.1071/MF97016.
1019
Tix, J.A., Hasler, C.T., Sullivan, C., Jeffrey, J.D., Suski, C.D., 2017. Elevated carbon dioxide has
1020
limited acute effects on Lepomis macrochirus behaviour. J. Fish Biol. 90, 751–772.
1021
https://doi.org/10.1111/jfb.13188.
1022
Vossen, L.E., Jutfelt, F., Cocco, A., Thörnqvist, P., Winberg, S., 2016. Zebra fish (Danio rerio)
1023
behaviour is largely unaffected by elevated pCO2. Conserv. Biol. 4, cow065.
1024
https://doi.org/10.1093/conphys/cow065.
1025
Watson, S.-A., Allan, B.J.M., Mcqueen, D.E., Nicol, S., Parsons, D.M., Pether, S.M.J., Pope, S.,
1026
Setiawan, A.N., Smith, N., Wilson, C., Munday, P.L., 2018. Ocean warming has a greater
1027
effect than acidification on the early life history development and swimming
1028
performance of a large circumglobal pelagic fish. Glob. Chang. Biol. 24, 4368-4385.
1029
https://doi.org/10.1111/gcb.14290.
1030 1031
Welch, M.J., Watson, S.-A., Welsh, J.Q., McCormick, M.I., Munday, P.L., 2014. Effects of elevated CO2 on fish behaviour undiminished by transgenerational acclimation. Nat. 45
1032 1033
Clim. Chang. 4, 1086–1089. https://doi.org/10.1038/nclimate2400. Williams, C.R., Dittman, A.H., McElhany, P., Busch, D.S., Maher, M.T., Bammler, T.K.,
1034
MacDonald, J.W., Gallagher, E.P., 2019. Elevated CO2 impairs olfactory-mediated neural
1035
and behavioral responses and gene expression in ocean-phase coho salmon
1036
(Oncorhynchus kisutch). Glob. Chang. Biol. 25, 963–977.
1037
https://doi.org/10.1111/gcb.14532.
1038
Winberg, S., Nilsson, G.E., 1993. Roles of brain monoamine neurotransmitters in agonistic
1039
behaviour and stress reactions, with particular reference to fish. Comp. Biochem.
1040
Physiol. Part C Comp. 106, 597–614. https://doi.org/10.1016/0742-8413(93)90216-8.
1041 1042
Wittmann, A.C., Pörtner, H., 2013. Sensitivities of extant animal taxa to ocean acidification. Nat. Clim. Chang. 3, 995–1001. https://doi.org/10.1038/nclimate1982.
1043 1044
46
Highlights
•
The effects of elevated CO2 on behaviours of kingfish were trait specific.
•
Elevated CO2 increased anxiety in kingfish.
•
Exposure to high temperature in isolation had no significant effect on any trait.
The authors declare no conflicts of interest.