Use of hedgerows as a key element of badger (Meles meles) behaviour in Ireland

Mammalian Biology 81 (2016) 104–110

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Original Investigation

Use of hedgerows as a key element of badger (Meles meles) behaviour in Ireland John O’Brien ∗ , Stephen Elliott, Thomas J. Hayden School of Biology and Environmental Sciences, University College Dublin, Belfield, Dublin 4, Ireland

a r t i c l e

i n f o

Article history: Received 3 April 2015 Accepted 14 October 2015 Handled by Adriano Martinoli Available online 21 October 2015 Keywords: Badger Hedgerows Foraging behaviour Setts Latrines

a b s t r a c t Human modification of landscapes is one of the greatest threats facing biodiversity worldwide and conversion of native habitat to agricultural land is widely perceived as contributing significantly to biodiversity declines. However, some species have proven to be adaptable to human-induced habitat change. Here, we show that over the course of the relatively short period of co-existence between badgers (Meles meles) and humans in Ireland, badgers have adapted to using the man-made field boundaries that have replaced native woodland. Our study population, which was located in an intensively managed agricultural landscape, predominantly located their setts and latrines in or alongside hedgerows. In addition, for the first time, we show that badgers selectively foraged along field boundaries, with this behaviour perhaps linked to a greater diversity of dietary items in hedgerows and the potential cover from perceived threats offered by dense undergrowth. This preferential use of man-made landscape features has implications for how we assess habitat use in this species and perhaps also for modelling studies of bovine tuberculosis transmission in agricultural landscapes. © 2015 Deutsche Gesellschaft für Säugetierkunde. Published by Elsevier GmbH. All rights reserved.

Introduction Much is made of the negative impact humans have in terms of modifying natural habitats, which tends to have dire consequences for wildlife (e.g. Sanderson et al., 2002; Leu et al., 2008; Newbold et al., 2014). However, over time, some species can adapt to these human impacts and a certain degree of co-existence can develop (e.g. Mavatur and Singh, 2010; Carter et al., 2012). In protected areas, where human impacts can be managed, the potential for human-wildlife conflict can be minimised, whereas in agricultural landscapes the human-wildlife interface is broad and the degree to which adaptations to human impacts can evolve is an important facet of conservation biology research for fauna in such landscapes (Carlson, 1985; Wright et al., 2012). Here, we examine how European badgers (Meles meles) have adapted their behaviour to modification of the Irish landscape by humans, with a particular focus on their preference for foraging along hedgerows (which are man-made constructions) and for locating setts and latrines in them. Although the timing of human arrival on Irish shores following extensive Midlandian (80,000–13,000 years BP) glacial coverage

∗ Corresponding author at: Brannoxtown, Trim, Co. Meath, Ireland. Tel.: +353 86 231 0395. E-mail address: [email protected] (J. O’Brien).

cannot be determined exactly, evidence suggests that humans were established on the island by the mid-Mesolithic (∼7500 years BP, Woodman, 1986). The earliest evidence for a field-based agricultural system in Ireland comes from the Céide Fields in western Ireland that date to about 5700 years BP (Caulfield et al., 1998). Extensive modification of the Irish landscape for agricultural purposes (both arable and pastoral) only began in the late 12th century and intensified in the 17th and 18th centuries, culminating in the early 20th century when less than 2% of the country is estimated to have been covered by forest (Smith et al., 2011; O’Hanlon, 2012). Despite considerable evolutions in agricultural practices in Ireland, pre-Christian field layouts persist in many areas of Ireland suggesting that the field boundaries in Ireland, and the hedgerows that define them, are very stable through time. Genetic and archaeological evidence seems to indicate that badgers only colonised Ireland following the arrival of humans and, in fact, were probably introduced by early human colonists (Frantz et al., 2014). Thus, badgers on the island of Ireland have evolved in concert with humans, adapting to increasingly pervasive anthropogenic impacts. Badgers in Ireland are generalist foragers, varying their diets across seasons and with earthworms forming an important though not predominant element of the diet (Cleary et al., 2009, 2011). Earthworm abundance tends to be higher on pasture fields compared to other land use types such as arable or forest (Cuendet, 1996), so farming practices may have a direct impact on badgers in terms of foraging behaviour. We have previously shown that

http://dx.doi.org/10.1016/j.mambio.2015.10.004 1616-5047/© 2015 Deutsche Gesellschaft für Säugetierkunde. Published by Elsevier GmbH. All rights reserved.

J. O’Brien et al. / Mammalian Biology 81 (2016) 104–110

badgers in Ireland largely avoid arable fields and actively select pasture fields when foraging (Elliott et al., 2015). Furthermore, hedgerows provide a broader diversity of potential foods compared to open fields (e.g. Thomas and Marshall, 1999; Facey et al., 2014) and we have also shown that badgers actively forage in hedgerows (Elliott et al., 2015). We hypothesised that our study badgers would selectively forage along field margins. We anticipated that such a pattern would occur because field boundaries would provide a greater diversity of potential dietary items than field centres (e.g. Thomas and Marshall, 1999; Facey et al., 2014), hedgerows would offer a degree of security and shelter to hide from threats such as humans and dogs (e.g. Hilty and Merenlender, 2004) and may act both as convenient landscape markers and impediments to free movement and, under some circumstances, the shade provided by trees and dense shrubs would generate an amenable microclimate that would favour earthworms (Hauser, 1993). Badger setts are important resources within a badger group’s territory (Macdonald et al., 2004), evidenced by their long-term persistence and use in the landscape and the considerable energetic investment spent by badgers in maintaining them (Stewart et al., 2001). Likewise, at least in medium to high density populations, badgers invest significant time in replenishing their network of latrines – preferred points for scent-marking, urination and faecal deposition that have a function in territorial defence and advertisement of reproductive status (Buesching and Macdonald, 2001) – which can have a significant impact on their nightly behavioural patterns (Loureiro et al., 2009). Hedgerows have already been reported as being important habitats for the location of badger setts in Ireland (Smal, 1995) and the UK (Hazel and French, 2000), and for latrine sites (Brown, 1993; Macdonald et al., 2004; Delahay et al., 2007; Balestrieri et al., 2011). We were interested in determining if such patterns of hedgerow use in terms of sett and latrine locations also occurred in our study population which, if combined with our investigation of selective foraging along field boundaries, would reinforce the importance of these man-made habitat features in the ecology of Irish badgers.

Material and methods Study area Our study area was located approximately 32 km north-east of the city of Dublin in eastern Ireland (53◦ 30 N, 6◦ 35 W) and covered approximately 11.36 km2 . The landscape is typical of rural areas in eastern Ireland with managed pasture predominating area coverage (74% overall – beef ∼27%, dairy ∼13%, sheep ∼5%, horses ∼4%, mixed ∼25%), interspersed with tracts of arable land (18% – wheat, oats and barley), particularly low woodland coverage (0.45%), and houses, farmyards and gardens (2%) concentrated along road margins. Since practically all field boundaries, roads, tracks and river banks in the study area featured a hedgerow, we did not classify these features separately in our analyses. The only exception was the area surrounding the Teagasc Agricultural Research Centre (TARC, Fig. 1A and B), where many of the original hedgerows had been removed and replaced with sheep wire or single-strand electric fencing to delimit fields (and we discuss this exception further in the discussion of our results). Hedgerows constituted 3% of the study area (i.e. greatly exceeding woodland coverage) and comprised mostly hawthorn (Crataegus monogyna), interspersed with trees such as ash (Fraxinus excelsior) and beech (Fagus sylvatica), with hedgerows in Meath having a mean width of 2.2 m [proportions of hedgerows in different width classes: <1 m = 0.02; 1–2 m = 0.39; 2–3 m = 0.49; >3 m = 0.1] and a density of 7.26 km/km2 , with most exceeding 2.5 m in height (Smith et al., 2011).

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A cull carried out by the Irish Department of Agriculture (December 1998 to January 1999) as part of their bovine tuberculosis control regime after our fieldwork had ceased indicated a minimum badger density in the study area of approximately 2 badgers/km2 , suggesting a population size of approximately 22–25 badgers in the study area, although it should be noted that estimates from a single trapping event can considerably underestimate badger numbers (Byrne et al., 2012; Noonan et al., 2015). A comprehensive survey of a non-culled population in similar habitat in Northern Ireland also estimated a mean badger density of 2.04 badgers/km2 (95% CI 0.68–3.41) (Reid et al., 2012) based on a mean social group size of 4.27 badgers/main sett (95% CI 3.65–4.89). Radiotelemetry and sett and latrine surveys The study area was first surveyed for badger setts in late 1994 and then in conjunction with bi-annual latrine bait-marking surveys. Latrine/sett surveys were carried out over a four-week period on seven separate occasions during the study period (Spring and Autumn in 1995, 1996 and 1997 and the Spring of 1998). Surveys involved walking the study area in daylight searching for both latrines and setts, and the area covered progressively increased with each survey (see Supplementary Material). We categorised setts as either main, annex, subsidiary or outlier following Thornton (1988). Bait-marking followed the protocol of Kruuk (1978), except our bait consisted of a chocolate/peanut base in which coloured plastic pellets (Athlone Extrusions Ltd.) were mixed – we acknowledge that nowadays chocolate is not considered a suitable bait for wildlife. Latrines presenting more than one colour pellet were considered boundary latrines, latrines with a unique colour pellet were considered hinterland, and latrines with no bait were termed ‘unbaited’ (Kilshaw et al., 2009). Radiotracking was carried out between February 1996 and May 1998. Badgers were captured in cage traps and anaesthetised by intra-muscular injection of 20 mg/kg ketamine hydrochloride (nowadays, a lower dose in conjunction with other agents is recommended, e.g. McLaren et al., 2005) under licence from the Office of Public Works, in association with the Department of Agriculture, Forestry & Food and according to the ethical standards of University College Dublin. Captured badgers were aged according to toothwear (da Silva and Macdonald, 1989) as adult (>2 years) and subadult (<2 years). Ten badgers (five males and five females) were radiotracked for various timeframes in the study period (see Supplementary Material and Elliott et al., 2015) using Yagi antennae and observed using hand-held night-vision monoculars. Tracking was typically carried out between 22:00 and 04:00 during which locations (fixes) and behaviour were recorded every 10 min, but tracking effort varied from night to night depending on how quickly a badger was located, if telemetry signals were lost or if a session had to end prematurely. Since radiotracked badgers were under continuous observation, we could characterise foraging behaviour as being typified by active searching in a meandering pathway, accompanied by audible lipsmacking noises. Our use of night-vision and the open nature of the landscape meant that both location (and behaviour) could be determined accurately so we did not generate error polygons around fixes. We only used fixes attributed to foraging activity in our analyses, so our results only pertain to that behaviour. Although this dataset is over 15 years old, since habitat structure and farming practices have changed little over the intervening years both within the study area and regionally (O’Brien, pers. obs.), we assert that our findings are still relevant today. Analysis Foraging fixes, setts and latrines were overlaid on a habitat raster in ArcMap 10.2.1 (ESRI, 2014). We selected fields where badgers

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Fig. 1. (A) Distribution of main (circles), subsidiary (asterisks), outlier (triangles) and annex (squares) setts in the study area. (B) Distribution of latrines in the study area, with shared (boundary) latrines overlaid with a diamond. Letters denote main setts: B = Blue, B/G = Blue-Green, Br = Brien, G = Green, Gr = Grange, R = Red, W = White, Y = Yellow. TARC = Teagasc Agricultural Research Centre.

Results Over 50% of all foraging fixes occurred within 20 m of a field boundary (see Fig. 2), while almost 60% of DISTANCE RATIO values of foraging fixes were less than 0.2 (which indicates close proximity to field edges whilst taking account of field size) (see Fig. 3). Both mean and median DISTANCE RATIO values for foraging fixes in individual fields differed significantly from random points (Wilcoxon test: Means W = 206, z = −4.93, p < 0.001; Medians W = 350, z = −3.79, p < 0.001). Thus, there was a very clear propensity for badgers to forage close to the hedgerows that typically

700 600 500 Frequency

400 300 200 100 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 >100

were observed foraging to assess spatial variation in field use. For each of the foraging fixes in those fields we calculated a DISTANCE RATIO of distance (in metres) to nearest field boundary divided by the distance to the field centroid and, in so doing, we accounted for variability in the size of fields. We then generated 100 randomly located fixes for each field in ArcMap 10.2.1 (ESRI, 2014) and calculated the DISTANCE RATIO for each of the random fixes in the same way. The mean and median DISTANCE RATIOS for both actual and random fixes for all selected fields were then compared using a Wilcoxon matched pair rank test. To investigate what factors might contribute to variability in DISTANCE RATIO, we conducted a generalised linear mixed effects model (GLMM) using the nlme package in R (R Core Team, 2014). We defined badger identity and field identity as random effects, DISTANCE RATIO as the response variable and SEX, AGE, FIELD TYPE (i.e. arable or pasture, since we have previously shown differential selectivity for habitat in this study population, Elliott et al., 2015) and DISTANCE TO SETT (i.e. distance of each foraging fix to the main sett of the badger to which the fix is attributed) as the fixed effects. Following Feore and Montgomery (1999), we employed a log-likelihood (G) goodness of fit analysis to evaluate if particular habitats were selected for both sett and latrine locations based on a habitat utilisation/availability comparison, while a Bonferroni Z approach (Beyers et al., 1994) was used to assess habitat preferences.

Distance to hedgerow (m) Fig. 2. Frequency distribution of foraging fixes in relation to distance in metres to the nearest hedgerow against random values (dotted line). Random values are represented by a dotted line.

bordered fields, and there was no difference in this behaviour between males and females (paired t test: Means t = −0.57, p = 0.29; Medians t = −1.64, p = 0.06) or between adults and juveniles (paired t test: Means t = 1.03, p = 0.16; Medians t = 0.65, p = 0.26). Neither the mean or median DISTANCE RATIO values differed between pasture and arable fields (t test: Means t = 1.57, p > 0.05; Medians t = 1.68, p > 0.05). Our GLMM corroborated these findings, with neither AGE, SEX nor FIELD TYPE contributing to the variability observed in DISTANCE RATIO values. DISTANCE TO SETT was the only fixed effect in our GLMM that impacted on the variability of the response variable, and its contribution was significant (p < 0.01). There were 8 main setts in the study area (see Fig. 1A), complemented by 16 other setts (2 annex, 5 subsidiary and 9 outlier), giving a main sett density of 0.71/km2 and an overall sett density of 2.14/km2 . Main setts had a mean 3.63 (±2.00) used entrances, 1.38 (±1.18) partially used entrances and 3.75 (±1.60) disused entrances. One main sett (Blue) was abandoned during the study period (in the winter of 1997), after having been illegally dug out

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Table 1 Sett distribution according to habitat type. Habitat type

Area (ha)a

Proportion of area

No. setts

Proportion of setts

Expected no. setts

Woodland Pasture fields Arable fields Hedgerows Quarry

50.83 8472.73 2083.72 341.24 41.98

0.004 0.771 0.190 0.031 0.004

2 1 0 19 2

0.083 0.042 0.000 0.792 0.083

0.10 18.50 4.56 0.74 0.10

CI 0–0.23 0–0.31b – 0.77–0.81† 0–0.23

a We do not consider private residences and farm buildings so our total area is not equal to the study area of 11.36 km2 . CI refers to the confidence interval for the proportion of setts calculated according to a Bonferroni Z approach (Beyers et al., 1994). b Preference/avoidance at ˛ = 0.05.

Table 2 Latrine data. % area surveyed indicates the percentage of the total study area that was examined for latrines and setts. Moran’s I is a measure of aggregation, with values ranging from −1 (dispersed) to +1 (clumped) – here values are given together with respective z scores and p values. Survey

No. of latrines

Density (latrines/km2 )

% Area surveyed

Moran’s I

z Score

p Value

Spring 95 Autumn 95 Spring 96 Autumn 96 Spring 97 Autumn 97 Spring 98

56 63 77 52 88 48 72

11.09 11.39 9.64 5.77 9.19 4.85 6.79

44.45 48.68 70.33 79.31 84.33 87.06 93.31

−0.02 −0.05 −0.01 0.04 −0.09 −0.02 0.02

−0.07 −0.35 0.14 0.77 −0.91 −0.01 0.84

0.9432 0.7264 0.8916 0.4441 0.3624 0.9908 0.4014

1400

latrines/survey, range 2–25%). The pattern of latrine distribution for all seven surveys appeared to be random based on Moran’s I aggregation analysis (see Table 2). In general, we found more latrines in spring surveys compared to autumn ones (see Table 2).

Frequency

1200 1000 800 600 400

Discussion

200 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

1

>1

Distance Rao Fig. 3. Frequency distribution of DISTANCE RATIO values for foraging fixes, with lower values indicating closer proximity to hedgerow relative to field centroid (values greater than one represent a location closer to the field centroid than the field edge).

by humans. There was a clear bias in habitat selection for sett location (X2 [4] = 543.892, p < 0.001), with a preference (p < 0.05) for locating setts in hedgerows based on the Bonferroni Z method. Nineteen of 24 setts were located in this latter habitat type (see Table 1). Nearest-neighbour analysis of main sett locations gave a mean nearest-neighbour distance between setts of 1.07 km (range: 0.63–1.93 km) and a tendency towards a uniform distribution (index of aggregation R = 1.81, |z| < 0.001) according to the protocol of Clark and Evans (1954). Fig. 1B shows the distribution of latrines from all seven surveys combined. There was a degree of habitat selectivity displayed by badgers in terms of latrine location. Latrines were sited significantly more frequently inside hedgerows (expected = 0.04; CI[observed values] = 0.16–0.29) and less frequently in pasture fields (expected = 0.75; CI[observed values] = 0.46–0.62) than might be expected based on respective proportions of habitat coverage in the study area. The low area coverage of woodland, human habitation and quarries meant that these habitats could not be meaningfully assessed. Although the proportion of latrines situated in cereal fields was higher than expected, this was not significant (expected = 0.18; CI[observed value] = 0.16–0.29). The mean distance of latrines to hedgerows in pasture and arable fields was 2.40 m (range: 0.01–64.15 m) and 1.58 m (range: 0.03–16.77 m), respectively. Overall, we identified 249 latrine sites within the study area (with an average survey density of 8.39 latrines/km2 , range 4.85–11.39), of which 63 were unbaited, 135 were hinterland latrines and 43 were boundary latrines (mean 11% boundary

As far as we are aware, this is the first time that badgers have been reported as selectively foraging along field boundaries. Since practically all field boundaries in our study area featured a hedgerow and those fields that did not possess such features were largely not utilised for foraging by badgers (see area around TARC in Fig. 4, where fields are typically delimited by sheep wire or single-strand electric fencing), we assert that it was the presence of these landscape features that drove this pattern. Clearly, it would be interesting to systematically assess differential field edge use by badgers in areas where both hedgerows and fencelines are distributed more evenly. The lack of differences between males and females or between juveniles and adults in terms of foraging close to hedgerows indicates that this biased use of the landscape is broadly characteristic of the behavioural repertoire of this population. The fact that badgers tended to forage more closely to field boundaries the further they were from their main sett suggests that, at least to some extent, security may play some role in eliciting this behaviour. Badgers may also choose to forage along hedgerows because of the enhanced dietary opportunities afforded by proximity to these features – i.e. greater abundances of invertebrate prey (e.g. Thomas and Marshall, 1999; Facey et al., 2014), berries, and small mammals and birds (e.g. Gelling et al., 2007). This suggestion is evidenced somewhat by the fact that badgers foraged close to hedgerows in both pasture and arable fields, even though arable fields are largely avoided for foraging by our study badgers (Elliott et al., 2015). Indeed, perhaps this preference for feeding along hedgerows is what makes Irish badgers dietary generalists (Cleary et al., 2009, 2011). Dietary analyses of badger populations in similar intensively managed agricultural landscapes where hedgerows predominate would certainly be informative in this respect, especially if linked to radiotracking and prey/food abundance studies. Our main sett density accords well with an estimate for similar habitat elsewhere in Ireland (0.71 versus 0.79/km2 ), although our overall sett density is considerably lower than that from the same

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Fig. 4. Distribution of foraging fixes in the study area (grey shading indicates pasture, whereas stippled shading represents arable fields) with detail showing a concentration of fixes around a field boundary (the varying symbols in the detail represent fixes by different badgers). TARC = Teagasc Agricultural Research Centre.

study (2.14 versus 4.31/km2 ) (Feore and Montgomery, 1999). As also reported by Smal (1995), we identified a strong preference for locating setts in hedgerows. This clear preference for hedgerows probably relates to the paucity of woodland coverage in the study area, since the hedgerows’ undergrowth shields a sett’s location and provides cover for badgers when emerging from sett entrances, while the roots of trees and shrubs provide an architecture through which stable passages and dens can be constructed. Remonti et al. (2006) also found that cover was an important determinant of sett location in an open landscape where the forested cover had been dramatically reduced. Interestingly, 4 of the 8 main setts in our study area were located at the junctures between arable and pasture land. Locating setts at such sites may maximise the availability of food resources near the sett when climatic or physiological factors inhibit long journeys, whilst also providing easy access to fresh bedding at certain times of the year. The majority of latrines were located either in hedgerows or close to them in both arable and pasture fields. In another Irish badger population, Feore and Montgomery (1999) also found that

most latrines (94.5%) were located within 5 m of a natural boundary. Brown (1993) suggested that hedgerows acted as convenient boundaries between territories (which he defined by radiotracking) and found that most latrines were associated with relatively impenetrable features such as netting or thick undergrowth. Balestrieri et al. (2011) also described a strong preference for badgers in northern Italy to site latrines at man-made landscape features (in that case, pathways). In contrast, Kruuk (1989) found that only 44% of latrines for an English population were located within 10 m of a boundary feature – although the number within 2 m of a hedge was higher than expected, the number within 2 m of a fence was lower than expected. We also noticed a considerable paucity of latrines in the area surrounding the TARC in our study site (see Fig. 1B), which is marked by the absence of hedgerows and where field boundaries are typically formed by man-made fences. This is despite the fact that it constituted part of the territory of one of our study badgers (see Elliott et al., 2015). This area is also notable for the lack of foraging activity (see Fig. 4), despite the predominance of favoured foraging habitat (pasture), which together suggests that removal

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of hedgerows from Irish landscapes could have a profound impact on badger ecology. Delahay et al. (2007) found that around 80% of the deviance in latrine location attributed to habitat type was explained by the presence or absence of woodland, and postulated that this was because the cover provided by the canopy facilitated longer persistence of scent-marks. Hedgerows would also provide cover for latrines in areas where woodland cover is limited. Our analysis of latrine distribution suggests that scent-marking locations were randomly distributed in relation to each other throughout our study area. This is perhaps to be expected from what appears to be a socially fluid badger population (Elliott et al., 2015), where territorial boundaries are less of an inhibitor to crossborder incursions and broadly distributed latrines are more likely to be encountered by non-group badgers. The propensity of badgers to forage and, thus, travel along field boundaries may be another reason why latrines tend to be preferentially located in and along hedgerows since encounter rates of these scent-marking locations will be higher. Lara-Romero et al. (2012a) used latrine locations as a surrogate for badger habitat selection in a semi-arid ecosystem in Spain. If this approach was used in our study area it would lead to erroneous conclusions because we found that latrines were located in arable fields, which we have previously shown to be largely avoided by foraging badgers (Elliott et al., 2015). In general, the farming communities in Britain and Ireland view badgers unfavourably due to their perceived role in the transmission of bovine tuberculosis (Mycobacterium bovis) to cattle. White et al. (1993) revealed a positive relationship between the density of hedgerows and the rate of herd breakdowns from bovine tuberculosis. This relationship was linked to the propensity of badgers to urinate/scent-mark when traversing a hedgerow, with contaminated excreta being the most likely route of tuberculosis transmission and higher densities of hedgerows resulting in higher concentrations of excreta being deposited. While it is difficult to perceive how feasible strategies could be developed to control contact rates between badger excreta and cattle at hedgerows, with cattle exclusion from field edges likely proving economically unviable, knowledge of the role of such features in badger ecology may assist in informing modelling studies of disease transmission.

Conclusion The strong links to hedgerows evidenced by our study badgers in practically all facets of their ecology reinforce the importance of these landscape features and the criticality of their conservation. Studies of some other carnivores have found a similar ˇ ˇ et al., 2009, 2010; Haigh, 2011; Cervinka et al., pattern (e.g. Salek 2013). In Ireland, the Wildlife (Amendment) Act (2000) prohibits hedge-cutting from March to September, though the majority of hedgerows in Meath are not managed in any way (Smith et al., 2011). A recent survey of hedgerows in Meath indicated that >80% were shown as field boundaries on maps from the 1840s, though a large proportion was expected to be much older (Smith et al., 2011), and this long-term persistence is probably also important to badgers. Our finding that an area where hedgerows have been removed (i.e. around the TARC) was not utilised by our study badgers (either for foraging or scent-marking) reinforces the considerable reliance of these badgers on these landscape features. This reliance has likely evolved in concert with human modification of Irish landscapes for agricultural purposes, which only intensified in the past 300–400 years, belying a relatively rapid adaption by Irish badgers to human-induced habitat change. Thus, although the lack of woodland in the Irish landscape could be perceived as limiting badger densities compared to populations in this habitat type in the UK, the rapid adaption of Irish badgers to utilising widely-available hedgerows as a substitute has meant densities higher than most

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