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King penguins as bio-indicators? Variations in the behaviours and energetic costs of foraging dives
Abstracts / Comparative Biochemistry and Physiology, Part A 146 (2007) S75–S86
physiological disturbances seen in mature cod. Cod crowded using a sweep net (prior to harvesting) increased ventilatory depth, and this information is currently being developed into an operational welfare indicator. Behavioural evidence of respiratory distress agrees with on-farm measurements of elevated blood haematocrit and blood lactate. Plasma sodium and chloride concentrations were unchanged during crowding, but physiological stress was shown by increased concentrations of plasma cortisol and glucose. We found significant differences in responses to crowding of different cages, likely to reflect genetic differences and past experiences. Further studies are currently aiming to develop robust and practical welfare indices to facilitate improved cod welfare. This work was co-funded by Scottish Aquacultural Research Forum and DEFRA (contract 021). doi:10.1016/j.cbpa.2007.01.100
A2.18 The trials and tribulations of migratory barnacle geese P. Butler, (Birmingham University, United Kingdom) One population of barnacle geese (Branta leucopsis) migrates a distance of over 2500 km between its wintering area on the Solway Firth, Scotland and its breeding areas on the island of Spitsbergen, Svalbard,. It well known that during Spring, they fly to Helgeland on the Norwegian coast where they spend 2– 3 weeks to fatten up in preparation for the breeding period. However, on the return trip in the Autumn, it was thought that they flew non-stop for about 2 days. Using satellite tracking transmitters and implanted heart rate data loggers, we have demonstrated that, in fact, the birds make several stops along the Norwegian coast during their journey south, although they do seem to have sufficient fat stores when they leave Svalbard to enable them to fly non-stop. Weather conditions seem to have an important influence on this behaviour. Although migratory flight is energetically expensive, daily energy expenditure during the moult period is almost as great as that during the periods of migration. Data from captive geese, indicate that during this period the birds lose body mass, but at the same time increase their absolute rate of resting oxygen consumption. In the wild, the adult birds have 4 to 6 weeks from regaining their ability to fly in which to lay down sufficient fat for the journey south and to build up their flight muscles. What is more, the juveniles are fledged at 7 weeks and are 12–13 weeks old when they embark on the long journey to Scotland. doi:10.1016/j.cbpa.2007.01.101
A2.19 King penguins as bio-indicators? Variations in the behaviours and energetic costs of foraging dives L. Halsey, P. Butler, (University of Birmingham, United Kingdom); Y. Handrich, (Institut Pluridisciplinaire Hubert
S81
Curien (IPCH), France); A. Fahlman, (North Pacific Universities Marine Mammal Research Consortium, United States); C. Bost, (Centre d'Etude Biologiques de Chizé-Centre National de la Recherche Scientifique, France) Penguins consume key species in the trophic chains of the Southern Oceans, making them prime candidates for use as bio-indicators of the Antarctic ecosystem. As such, it is important that useful inferences can be made about their food requirements. This is achievable by measuring total metabolic rate, an important element of which is associated with foraging. Heart rate data loggers were implanted into king penguins during three austral summers. Data were obtained while birds were undertaking foraging trips at sea. We investigated variations in mean heart rate over the dive cycle with changes in diving behaviour, at the scale of the individual foraging dive. From these heart rate values, energetic costs were estimated in terms of rate of oxygen consumption. It was found that shorter dive durations, shorter bottom periods and longer surface durations were associated with significantly higher mean heart rates over the dive cycle, suggesting higher energetic costs. The birds of field season 3 spent much less time at sea to regain lost body mass than those of season 2 (9 ± 1 v. 32 ± 3 days). They also exhibited significantly longer dive durations (256.3 ± 7.3 v. 237.4 ± 5 s) and bottom durations (74.0 ± 0.9 v. 57.4 ± 2.3 s), slightly shorter surface durations and dived to significantly shallower depths (114.2 ± 10.2 v. 129.3 ± 6.9 m). However, this did not translate into a significantly lower mean heart rate in the birds of field season 3 while foraging. The implications of these findings in terms of the use of king penguins to assess changes in the marine environment are discussed. doi:10.1016/j.cbpa.2007.01.102
A2.20 Integrating physiology, behaviour and ecology: The diverse approach to a coherent blueprint for conservation P. Frappell, (La Trobe University, Australia) The capacity for acclimitisation is to a large extent dependent on genetic potential. On the other hand, phenotypic plasticity enables the tradeoffs between various behaviours (foraging, reproductive effort, etc.), ideal niches (thermal, aerobic, etc.), environmental influences and physiological function that determine why ‘an animal does what it does and when it does it’. To develop unifying principles that underscore the basic processes determining the distribution, composition and dynamics of species, populations and communities it is imperative that we understand the free-living animal. It is only then that can we provide statements about biodiversity management that are rigorous and able to be tested. Using diverse examples, this talk emphasizes the importance of
physiological disturbances seen in mature cod. Cod crowded using a sweep net (prior to harvesting) increased ventilatory depth, and this information is currently being developed into an operational welfare indicator. Behavioural evidence of respiratory distress agrees with on-farm measurements of elevated blood haematocrit and blood lactate. Plasma sodium and chloride concentrations were unchanged during crowding, but physiological stress was shown by increased concentrations of plasma cortisol and glucose. We found significant differences in responses to crowding of different cages, likely to reflect genetic differences and past experiences. Further studies are currently aiming to develop robust and practical welfare indices to facilitate improved cod welfare. This work was co-funded by Scottish Aquacultural Research Forum and DEFRA (contract 021). doi:10.1016/j.cbpa.2007.01.100
A2.18 The trials and tribulations of migratory barnacle geese P. Butler, (Birmingham University, United Kingdom) One population of barnacle geese (Branta leucopsis) migrates a distance of over 2500 km between its wintering area on the Solway Firth, Scotland and its breeding areas on the island of Spitsbergen, Svalbard,. It well known that during Spring, they fly to Helgeland on the Norwegian coast where they spend 2– 3 weeks to fatten up in preparation for the breeding period. However, on the return trip in the Autumn, it was thought that they flew non-stop for about 2 days. Using satellite tracking transmitters and implanted heart rate data loggers, we have demonstrated that, in fact, the birds make several stops along the Norwegian coast during their journey south, although they do seem to have sufficient fat stores when they leave Svalbard to enable them to fly non-stop. Weather conditions seem to have an important influence on this behaviour. Although migratory flight is energetically expensive, daily energy expenditure during the moult period is almost as great as that during the periods of migration. Data from captive geese, indicate that during this period the birds lose body mass, but at the same time increase their absolute rate of resting oxygen consumption. In the wild, the adult birds have 4 to 6 weeks from regaining their ability to fly in which to lay down sufficient fat for the journey south and to build up their flight muscles. What is more, the juveniles are fledged at 7 weeks and are 12–13 weeks old when they embark on the long journey to Scotland. doi:10.1016/j.cbpa.2007.01.101
A2.19 King penguins as bio-indicators? Variations in the behaviours and energetic costs of foraging dives L. Halsey, P. Butler, (University of Birmingham, United Kingdom); Y. Handrich, (Institut Pluridisciplinaire Hubert
S81
Curien (IPCH), France); A. Fahlman, (North Pacific Universities Marine Mammal Research Consortium, United States); C. Bost, (Centre d'Etude Biologiques de Chizé-Centre National de la Recherche Scientifique, France) Penguins consume key species in the trophic chains of the Southern Oceans, making them prime candidates for use as bio-indicators of the Antarctic ecosystem. As such, it is important that useful inferences can be made about their food requirements. This is achievable by measuring total metabolic rate, an important element of which is associated with foraging. Heart rate data loggers were implanted into king penguins during three austral summers. Data were obtained while birds were undertaking foraging trips at sea. We investigated variations in mean heart rate over the dive cycle with changes in diving behaviour, at the scale of the individual foraging dive. From these heart rate values, energetic costs were estimated in terms of rate of oxygen consumption. It was found that shorter dive durations, shorter bottom periods and longer surface durations were associated with significantly higher mean heart rates over the dive cycle, suggesting higher energetic costs. The birds of field season 3 spent much less time at sea to regain lost body mass than those of season 2 (9 ± 1 v. 32 ± 3 days). They also exhibited significantly longer dive durations (256.3 ± 7.3 v. 237.4 ± 5 s) and bottom durations (74.0 ± 0.9 v. 57.4 ± 2.3 s), slightly shorter surface durations and dived to significantly shallower depths (114.2 ± 10.2 v. 129.3 ± 6.9 m). However, this did not translate into a significantly lower mean heart rate in the birds of field season 3 while foraging. The implications of these findings in terms of the use of king penguins to assess changes in the marine environment are discussed. doi:10.1016/j.cbpa.2007.01.102
A2.20 Integrating physiology, behaviour and ecology: The diverse approach to a coherent blueprint for conservation P. Frappell, (La Trobe University, Australia) The capacity for acclimitisation is to a large extent dependent on genetic potential. On the other hand, phenotypic plasticity enables the tradeoffs between various behaviours (foraging, reproductive effort, etc.), ideal niches (thermal, aerobic, etc.), environmental influences and physiological function that determine why ‘an animal does what it does and when it does it’. To develop unifying principles that underscore the basic processes determining the distribution, composition and dynamics of species, populations and communities it is imperative that we understand the free-living animal. It is only then that can we provide statements about biodiversity management that are rigorous and able to be tested. Using diverse examples, this talk emphasizes the importance of