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Benowitz-Fredericks ZM, Will AP, Pete SN, Whelan S, Kitaysky AS. Corticosterone release in very young siblicidal seabird chicks (Rissa tridactyla) is sensitive to environmental variability and responds rapidly and robustly to external challenges. Gen Comp Endocrinol 2024; 355:114545. [PMID: 38701975 DOI: 10.1016/j.ygcen.2024.114545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 04/25/2024] [Accepted: 04/30/2024] [Indexed: 05/06/2024]
Abstract
In birds, patterns of development of the adrenocortical response to stressors vary among individuals, types of stressors, and species. Since there are benefits and costs of exposure to elevated glucocorticoids, this variation is presumably a product of selection such that animals modulate glucocorticoid secretion in contexts where doing so increases their fitness. In this study, we evaluated hypothalamo-pituitary-adrenal (HPA) activity in first-hatched free-living seabird nestlings that engage in intense sibling competition and facultative siblicide (black-legged kittiwakes, Rissa tridactyla). We sampled 5 day old chicks (of the ∼45 day nestling period), a critical early age when food availability drives establishment of important parent-offspring and intra-brood dynamics. We experimentally supplemented parents with food ("supplemented") and measured chick baseline corticosterone secretion and capacity to rapidly increase corticosterone in response to an acute challenge (handling and 15 min of restraint in a bag). We also used topical administration of corticosterone to evaluate the ability of chicks to downregulate physiologically relevant corticosterone levels on a short time scale (minutes). We found that 5 day old chicks are not hypo-responsive but release corticosterone in proportion to the magnitude of the challenge, showing differences in baseline between parental feeding treatments (supplemented vs non-supplemented), moderate increases in response to handling, and a larger response to restraint (comparable to adults) that also differed between chicks from supplemented and control nests. Topical application of exogenous corticosterone increased circulating levels nearly to restraint-induced levels and induced downregulation of HPA responsiveness to the acute challenge of handling. Parental supplemental feeding did not affect absorbance/clearance or negative feedback. Thus, while endogenous secretion of corticosterone in young chicks is sensitive to environmental context, other aspects of the HPA function, such as rapid negative feedback and/or the ability to clear acute elevations in corticosterone, are not. We conclude that 5 day old kittiwake chicks are capable of robust adrenocortical responses to novel challenges, and are sensitive to parental food availability, which may be transduced behaviorally, nutritionally, or via maternal effects. Questions remain about the function of such rapid, large acute stress-induced increases in corticosterone in very young chicks.
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Affiliation(s)
| | - A P Will
- World Wildlife Fund, US Arctic Program, United States; University of Alaska Fairbanks, Department of Biology and Wildlife, Institute of Arctic Biology, United States
| | - S N Pete
- Bucknell University, Department of Biology, 1 Dent Drive, Lewisburg, PA, United States
| | - S Whelan
- Institute for Seabird Research and Conservation, United States
| | - A S Kitaysky
- University of Alaska Fairbanks, Department of Biology and Wildlife, Institute of Arctic Biology, United States
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2
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Cruz-Flores M, Lemaire J, Brault-Favrou M, Christensen-Dalsgaard S, Churlaud C, Descamps S, Elliott K, Erikstad KE, Ezhov A, Gavrilo M, Grémillet D, Guillou G, Hatch S, Huffeldt NP, Kitaysky AS, Kolbeinsson Y, Krasnov Y, Langset M, Leclaire S, Linnebjerg JF, Lorentzen E, Mallory ML, Merkel FR, Montevecchi W, Mosbech A, Patterson A, Perret S, Provencher JF, Reiertsen TK, Renner H, Strøm H, Takahashi A, Thiebot JB, Thórarinsson TL, Will A, Bustamante P, Fort J. Spatial distribution of selenium-mercury in Arctic seabirds. Environ Pollut 2024; 343:123110. [PMID: 38086506 DOI: 10.1016/j.envpol.2023.123110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 11/19/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023]
Abstract
Mercury (Hg) is a metallic trace element toxic for humans and wildlife that can originate from natural and anthropic sources. Hg spatial gradients have been found in seabirds from the Arctic and other oceans, suggesting contrasting toxicity risks across regions. Selenium (Se) plays a protective role against Hg toxicity, but its spatial distribution has been much less investigated than that of Hg. From 2015 to 2017, we measured spatial co-exposure of Hg and Se in blood samples of two seabird species, the Brünnich's guillemot (Uria lomvia) and the black-legged kittiwake (Rissa tridactyla) from 17 colonies in the Arctic and subarctic regions, and we calculated their molar ratios (Se:Hg), as a measure of Hg sequestration by Se and, therefore, of Hg exposure risk. We also evaluated concentration differences between species and ocean basins (Pacific-Arctic and Atlantic-Arctic), and examined the influence of trophic ecology on Hg and Se concentrations using nitrogen and carbon stable isotopes. In the Atlantic-Arctic ocean, we found a negative west-to-east gradient of Hg and Se for guillemots, and a positive west-to-east gradient of Se for kittiwakes, suggesting that these species are better protected from Hg toxicity in the European Arctic. Differences in Se gradients between species suggest that they do not follow environmental Se spatial variations. This, together with the absence of a general pattern for isotopes influence on trace element concentrations, could be due to foraging ecology differences between species. In both oceans, the two species showed similar Hg concentrations, but guillemots showed lower Se concentrations and Se:Hg than kittiwakes, suggesting a higher Hg toxicity risk in guillemots. Within species, neither Hg, nor Se or Se:Hg differed between both oceans. Our study highlights the importance of considering Se together with Hg, along with different species and regions, when evaluating Hg toxic effects on marine predators in international monitoring programs.
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Affiliation(s)
- Marta Cruz-Flores
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000 La Rochelle, France.
| | - Jérémy Lemaire
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000 La Rochelle, France; Department of Behavioral and Cognitive Biology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Maud Brault-Favrou
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000 La Rochelle, France
| | | | - Carine Churlaud
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000 La Rochelle, France
| | | | - Kyle Elliott
- Department of Natural Resource Sciences, McGill University. Ste Anne-de-Bellevue, Quebec, Canada H9X 3V9
| | | | - Alexey Ezhov
- Murmansk Marine Biological Institute Russian Academy of Science, 183010 Vladimirskaya Str. 17, Murmansk, Russia
| | - Maria Gavrilo
- Arctic and Antarctic Research Institute. 199397 St. Petersburg, Russia
| | - David Grémillet
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France; Percy FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, South Africa
| | - Gaël Guillou
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000 La Rochelle, France
| | - Scott Hatch
- U.S. Geological Survey, Alaska Science Center. Anchorage, AK 99508, USA
| | - Nicholas Per Huffeldt
- Greenland Institute of Natural Resources, 3900 Nuuk, Greenland; Department of Ecoscience, Aarhus University. 4000 Roskilde, Denmark
| | - Alexander S Kitaysky
- University of Alaska Fairbanks, Institute of Arctic Biology, Department of Biology & Wildlife. Fairbanks, AK 99775-7000, USA
| | | | - Yuri Krasnov
- Murmansk Marine Biological Institute Russian Academy of Science, 183010 Vladimirskaya Str. 17, Murmansk, Russia
| | | | - Sarah Leclaire
- Laboratoire Evolution et Diversité Biologique (EDB), UMR 5174, Université de Toulouse, CNRS, IRD. 31062 Toulouse, France
| | | | | | - Mark L Mallory
- Biology, Acadia University, Wolfville, Nova Scotia B4P 2R6, Canada
| | - Flemming R Merkel
- Greenland Institute of Natural Resources, 3900 Nuuk, Greenland; Department of Ecoscience, Aarhus University. 4000 Roskilde, Denmark
| | - William Montevecchi
- Memorial University of Newfoundland and Labrador. St. John's, Newfoundland A1C 3X9, Canada
| | - Anders Mosbech
- Department of Ecoscience, Aarhus University. 4000 Roskilde, Denmark
| | - Allison Patterson
- Department of Natural Resource Sciences, McGill University. Ste Anne-de-Bellevue, Quebec, Canada H9X 3V9
| | - Samuel Perret
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Jennifer F Provencher
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, Ottawa, Ontario, Canada, K1A 0H3
| | - Tone K Reiertsen
- Norwegian Institute for Nature Research, FRAM Centre. 9296 Tromsø, Norway
| | - Heather Renner
- U.S. Fish and Wildlife Service, Alaska Maritime Wildlife Refuge, Homer, AK, USA
| | - Hallvard Strøm
- Norwegian Polar Institute, Fram Centre. 9296 Tromsø, Norway
| | - Akinori Takahashi
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa. Tokyo 190-8518, Japan
| | - Jean-Baptiste Thiebot
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa. Tokyo 190-8518, Japan; Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate, Hokkaido 041-8611, Japan
| | | | - Alexis Will
- University of Alaska Fairbanks, Institute of Arctic Biology, Department of Biology & Wildlife. Fairbanks, AK 99775-7000, USA; World Wildlife Fund, US Arctic Program, 810 N Street, Suite 300, Anchorage AK 99501, USA
| | - Paco Bustamante
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000 La Rochelle, France
| | - Jérôme Fort
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000 La Rochelle, France
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3
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Chastel O, Fort J, Ackerman JT, Albert C, Angelier F, Basu N, Blévin P, Brault-Favrou M, Bustnes JO, Bustamante P, Danielsen J, Descamps S, Dietz R, Erikstad KE, Eulaers I, Ezhov A, Fleishman AB, Gabrielsen GW, Gavrilo M, Gilchrist G, Gilg O, Gíslason S, Golubova E, Goutte A, Grémillet D, Hallgrimsson GT, Hansen ES, Hanssen SA, Hatch S, Huffeldt NP, Jakubas D, Jónsson JE, Kitaysky AS, Kolbeinsson Y, Krasnov Y, Letcher RJ, Linnebjerg JF, Mallory M, Merkel FR, Moe B, Montevecchi WJ, Mosbech A, Olsen B, Orben RA, Provencher JF, Ragnarsdottir SB, Reiertsen TK, Rojek N, Romano M, Søndergaard J, Strøm H, Takahashi A, Tartu S, Thórarinsson TL, Thiebot JB, Will AP, Wilson S, Wojczulanis-Jakubas K, Yannic G. Mercury contamination and potential health risks to Arctic seabirds and shorebirds. Sci Total Environ 2022; 844:156944. [PMID: 35752241 DOI: 10.1016/j.scitotenv.2022.156944] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 06/20/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Since the last Arctic Monitoring and Assessment Programme (AMAP) effort to review biological effects of mercury (Hg) on Arctic biota in 2011 and 2018, there has been a considerable number of new Arctic bird studies. This review article provides contemporary Hg exposure and potential health risk for 36 Arctic seabird and shorebird species, representing a larger portion of the Arctic than during previous AMAP assessments now also including parts of the Russian Arctic. To assess risk to birds, we used Hg toxicity benchmarks established for blood and converted to egg, liver, and feather tissues. Several Arctic seabird populations showed Hg concentrations that exceeded toxicity benchmarks, with 50 % of individual birds exceeding the "no adverse health effect" level. In particular, 5 % of all studied birds were considered to be at moderate or higher risk to Hg toxicity. However, most seabirds (95 %) were generally at lower risk to Hg toxicity. The highest Hg contamination was observed in seabirds breeding in the western Atlantic and Pacific Oceans. Most Arctic shorebirds exhibited low Hg concentrations, with approximately 45 % of individuals categorized at no risk, 2.5 % at high risk category, and no individual at severe risk. Although the majority Arctic-breeding seabirds and shorebirds appeared at lower risk to Hg toxicity, recent studies have reported deleterious effects of Hg on some pituitary hormones, genotoxicity, and reproductive performance. Adult survival appeared unaffected by Hg exposure, although long-term banding studies incorporating Hg are still limited. Although Hg contamination across the Arctic is considered low for most bird species, Hg in combination with other stressors, including other contaminants, diseases, parasites, and climate change, may still cause adverse effects. Future investigations on the global impact of Hg on Arctic birds should be conducted within a multi-stressor framework. This information helps to address Article 22 (Effectiveness Evaluation) of the Minamata Convention on Mercury as a global pollutant.
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Affiliation(s)
- Olivier Chastel
- Centre d'Etudes Biologiques de Chizé (CEBC), UMR 7372 CNRS- La Rochelle Université, 79360 Villiers-en-Bois, France.
| | - Jérôme Fort
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 17000 La Rochelle, France.
| | - Joshua T Ackerman
- U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States.
| | - Céline Albert
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 17000 La Rochelle, France
| | - Frédéric Angelier
- Centre d'Etudes Biologiques de Chizé (CEBC), UMR 7372 CNRS- La Rochelle Université, 79360 Villiers-en-Bois, France
| | - Niladri Basu
- McGill University, Faculty of Agriculture and Environmental Sciences, Montreal, QC H9X 3V9, Canada
| | | | - Maud Brault-Favrou
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 17000 La Rochelle, France
| | - Jan Ove Bustnes
- Norwegian Institute for Nature Research, FRAM Centre, 9296 Tromsø, Norway
| | - Paco Bustamante
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 17000 La Rochelle, France; Institut Universitaire de France (IUF), 75005 Paris, France
| | | | | | - Rune Dietz
- Department of Ecoscience, Aarhus University, 4000 Roskilde, Denmark
| | | | - Igor Eulaers
- Norwegian Polar Institute, Fram center, 9296 Tromsø, Norway; Department of Ecoscience, Aarhus University, 4000 Roskilde, Denmark
| | - Alexey Ezhov
- Murmansk Marine Biological Institute Russian Academy of Science, 183010 Vladimirskaya str. 17 Murmansk, Russia
| | - Abram B Fleishman
- Conservation Metrics, Inc., Santa Cruz, CA, United States of America
| | | | - Maria Gavrilo
- Arctic and Antarctic Research Institute, 199397 St. Petersburg, Russia
| | - Grant Gilchrist
- Environment and Climate Change Canada, National Wildlife Research Centre, 1125 Colonel By Drive, Raven Road, Carleton University, Ottawa, Ont., Canada K1A 0H3
| | - Olivier Gilg
- Laboratoire Chrono-environnement, UMR 6249, Université de Bourgogne Franche Comté, 25000 Besançon, France; Groupe de Recherche en Ecologie Arctique, 16 rue de Vernot, F-21440 Francheville, France
| | - Sindri Gíslason
- Southwest Iceland Nature Research Centre, Gardvegur 1, 245 Sudurnesjabaer, Iceland
| | - Elena Golubova
- Laboratory of Ornithology, Institute of Biological Problems of the North, RU-685000 Magadan, Portovaya Str., 18, Russia
| | - Aurélie Goutte
- EPHE, PSL Research University, UMR 7619 METIS, F-75005 Paris, France
| | - David Grémillet
- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), UMR 5175 Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France,; Percy FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, South Africa
| | - Gunnar T Hallgrimsson
- Department of Life and Environmental Sciences, University of Iceland, 102 Reykjavik, Iceland
| | - Erpur S Hansen
- South Iceland Nature Research Centre, Ægisgata 2, 900 Vestmannaeyjar, Iceland
| | | | - Scott Hatch
- Institute for Seabird Research and Conservation, Anchorage, 99516-3185, AK, USA
| | - Nicholas P Huffeldt
- Department of Ecoscience, Aarhus University, 4000 Roskilde, Denmark; Greenland Institute of Natural Resources, 3900 Nuuk, Greenland
| | - Dariusz Jakubas
- Department of Vertebrate Ecology and Zoology, University of Gdansk, 80-308 Gdansk, Poland
| | - Jón Einar Jónsson
- University of Iceland's Research Center at Snæfellsnes, 340 Stykkishólmur, Iceland
| | - Alexander S Kitaysky
- University of Alaska Fairbanks, Institute of Arctic Biology, Department of Biology & Wildlife, Fairbanks, AK 99775-7000, United States of America
| | | | - Yuri Krasnov
- Murmansk Marine Biological Institute Russian Academy of Science, 183010 Vladimirskaya str. 17 Murmansk, Russia
| | - Robert J Letcher
- Environment and Climate Change Canada, National Wildlife Research Centre, 1125 Colonel By Drive, Raven Road, Carleton University, Ottawa, Ont., Canada K1A 0H3
| | | | - Mark Mallory
- Biology, Acadia University Wolfville, Nova Scotia B4P 2R6, Canada
| | - Flemming Ravn Merkel
- Department of Ecoscience, Aarhus University, 4000 Roskilde, Denmark; Greenland Institute of Natural Resources, 3900 Nuuk, Greenland
| | - Børge Moe
- Norwegian Institute for Nature Research, 7485 Trondheim, Norway
| | - William J Montevecchi
- Memorial Univerisity of Newfoundland and Labrador, St. John's, Newoundland A1C 3X9, Canada
| | - Anders Mosbech
- Department of Ecoscience, Aarhus University, 4000 Roskilde, Denmark
| | - Bergur Olsen
- Faroe Marine Reseaqrch Institute, Nóatún 1, FO-110 Tórshavn, Faroe Islands
| | - Rachael A Orben
- Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Hatfield Marine Science Center, Newport, OR, USA
| | - Jennifer F Provencher
- Science & Technology Branch, Environment and Climate Change Canada, Ottawa, Ontario, Canada K1A 0H3
| | | | - Tone K Reiertsen
- Norwegian Institute for Nature Research, FRAM Centre, 9296 Tromsø, Norway
| | - Nora Rojek
- U.S. Fish and Wildlife Service, Alaska Maritime Wildlife Refuge, Homer, AK, USA
| | - Marc Romano
- U.S. Fish and Wildlife Service, Alaska Maritime Wildlife Refuge, Homer, AK, USA
| | - Jens Søndergaard
- Department of Ecoscience, Aarhus University, 4000 Roskilde, Denmark
| | - Hallvard Strøm
- Norwegian Polar Institute, Fram center, 9296 Tromsø, Norway
| | - Akinori Takahashi
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo 190-8518, Japan
| | - Sabrina Tartu
- Centre d'Etudes Biologiques de Chizé (CEBC), UMR 7372 CNRS- La Rochelle Université, 79360 Villiers-en-Bois, France
| | | | - Jean-Baptiste Thiebot
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo 190-8518, Japan
| | - Alexis P Will
- University of Alaska Fairbanks, Institute of Arctic Biology, Department of Biology & Wildlife, Fairbanks, AK 99775-7000, United States of America; National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo 190-8518, Japan
| | - Simon Wilson
- Arctic Monitoring and Assessment Programme (AMAP) Secretariat, The Fram Centre, Box 6606, Stakkevollan, 9296, Tromsø, Norway
| | | | - Glenn Yannic
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, 38000 Grenoble, France
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Fleishman AB, Orben RA, Kokubun N, Will A, Paredes R, Ackerman JT, Takahashi A, Kitaysky AS, Shaffer SA. Wintering in the Western Subarctic Pacific Increases Mercury Contamination of Red-Legged Kittiwakes. Environ Sci Technol 2019; 53:13398-13407. [PMID: 31693348 DOI: 10.1021/acs.est.9b03421] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Marine methylmercury concentrations vary geographically and with depth, exposing organisms to different mercury levels in different habitats. Red-legged kittiwakes (Rissa brevirostris), a specialist predator, forage on fish and invertebrates from the mesopelagic zone, a part of the ocean with elevated methylmercury concentrations. We used kittiwakes as bioindicators of MeHg concentrations in remote mesopelagic systems by examining how wintering distribution and habitat affected kittiwakes' mercury exposure. In 2011-2017, we sampled winter-grown feathers on St. George Island, Alaska, from birds equipped with geolocation loggers. We measured total mercury (THg) and nitrogen stable isotopes in nape and head feathers grown during winter, respectively. THg concentration of kittiwake nape feathers averaged 4.61 ± 0.97 μg/g dry weight. Hierarchical cluster analysis was used to classify winter habitats with remotely sensed environmental variables along each bird's track. Five habitat clusters were identified. Birds that spent more time in the Western Subarctic Gyre and those that wintered further south had elevated THg concentrations. In contrast to THg, trophic level varied annually but did not show strong spatial patterns. Our results documented spatial variability in THg exposure based on the oceanic wintering locations of red-legged kittiwakes and highlight their use as a bioindicator of MeHg across ocean basins.
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Affiliation(s)
- Abram B Fleishman
- Department of Biological Sciences , San Jose State University , One Washington Square, San Jose , California 95192-0100 , United States
- Conservation Metrics, Inc. , 145 McAllister Way , Santa Cruz , California 95060 , United States
| | - Rachael A Orben
- Department of Fisheries and Wildlife , Oregon State University, Hatfield Marine Science Center , 2030 SE Marine Science Dr. , Newport , Oregon 97365 , United States
| | - Nobuo Kokubun
- National Institute of Polar Research , 10-3 Midori-cho , Tachikawa , Tokyo 190-8518 , Japan
| | - Alexis Will
- National Institute of Polar Research , 10-3 Midori-cho , Tachikawa , Tokyo 190-8518 , Japan
| | - Rosana Paredes
- Department of Fisheries and Wildlife , Oregon State University , 104 Nash Hall , Corvallis , Oregon 97331-3803 United States
| | - Joshua T Ackerman
- U.S. Geological Survey , Western Ecological Research Center , Dixon Field Station, 800 Business Park Drive, Suite D , Dixon , California 95620 , United States
| | - Akinori Takahashi
- National Institute of Polar Research , 10-3 Midori-cho , Tachikawa , Tokyo 190-8518 , Japan
| | - Alexander S Kitaysky
- Department of Biology and Wildlife, Institute of Arctic Biology , University of Alaska Fairbanks , Irving 311 , Fairbanks , Alaska 99775 , United States
| | - Scott A Shaffer
- Department of Biological Sciences , San Jose State University , One Washington Square, San Jose , California 95192-0100 , United States
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5
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Wilbur SM, Barnes BM, Kitaysky AS, Williams CT. Tissue-specific telomere dynamics in hibernating arctic ground squirrels ( Urocitellus parryii). ACTA ACUST UNITED AC 2019; 222:jeb.204925. [PMID: 31515236 DOI: 10.1242/jeb.204925] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 09/03/2019] [Indexed: 01/25/2023]
Abstract
Hibernation is used by a variety of mammals to survive seasonal periods of resource scarcity. Reactive oxygen species (ROS) released during periodic rewarming throughout hibernation, however, may induce oxidative damage in some tissues. Telomeres, which are the terminal sequences of linear chromosomes, may shorten in the presence of ROS, and thus the telomere length of an individual reflects the degree of accrued oxidative damage. This study quantified telomere length dynamics throughout hibernation in arctic ground squirrels (Urocitellus parryii). We hypothesized that telomere dynamics are tissue specific and predicted that telomere shortening would be most pronounced in brown adipose tissue (BAT), the organ that directly supports non-shivering thermogenesis during arousals. We used qPCR to determine relative telomere length (RTL) in DNA extracted from liver, heart, skeletal muscle (SM) and BAT of 45 juvenile and adult animals sampled either at mid- or late hibernation. Age did not have a significant effect on RTL in any tissue. At mid-hibernation, RTL of juvenile females was longer in BAT and SM than in liver and heart. In juvenile females, RTL in BAT and SM, but not in liver and heart, was shorter at late hibernation than at mid-hibernation. At late hibernation, juvenile males had longer RTL in BAT than did juvenile females, perhaps due to the naturally shorter hibernation duration of male arctic ground squirrels. Finally, BAT RTL at late hibernation negatively correlated with arousal frequency. Overall, our results suggest that, in a hibernating mammal, telomere shortening is tissue specific and that metabolically active tissues might incur higher levels of molecular damage.
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Affiliation(s)
- Sara M Wilbur
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Brian M Barnes
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Alexander S Kitaysky
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Cory T Williams
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
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6
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Tricola GM, Simons MJP, Atema E, Boughton RK, Brown JL, Dearborn DC, Divoky G, Eimes JA, Huntington CE, Kitaysky AS, Juola FA, Lank DB, Litwa HP, Mulder EGA, Nisbet ICT, Okanoya K, Safran RJ, Schoech SJ, Schreiber EA, Thompson PM, Verhulst S, Wheelwright NT, Winkler DW, Young R, Vleck CM, Haussmann MF. The rate of telomere loss is related to maximum lifespan in birds. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2016.0445. [PMID: 29335369 PMCID: PMC5784065 DOI: 10.1098/rstb.2016.0445] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/02/2017] [Indexed: 02/06/2023] Open
Abstract
Telomeres are highly conserved regions of DNA that protect the ends of linear chromosomes. The loss of telomeres can signal an irreversible change to a cell's state, including cellular senescence. Senescent cells no longer divide and can damage nearby healthy cells, thus potentially placing them at the crossroads of cancer and ageing. While the epidemiology, cellular and molecular biology of telomeres are well studied, a newer field exploring telomere biology in the context of ecology and evolution is just emerging. With work to date focusing on how telomere shortening relates to individual mortality, less is known about how telomeres relate to ageing rates across species. Here, we investigated telomere length in cross-sectional samples from 19 bird species to determine how rates of telomere loss relate to interspecific variation in maximum lifespan. We found that bird species with longer lifespans lose fewer telomeric repeats each year compared with species with shorter lifespans. In addition, phylogenetic analysis revealed that the rate of telomere loss is evolutionarily conserved within bird families. This suggests that the physiological causes of telomere shortening, or the ability to maintain telomeres, are features that may be responsible for, or co-evolved with, different lifespans observed across species.This article is part of the theme issue 'Understanding diversity in telomere dynamics'.
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Affiliation(s)
- Gianna M Tricola
- Department of Biology, Bucknell University, Lewisburg, PA 17837, USA
| | - Mirre J P Simons
- Department of Animal and Plant Sciences, The University of Sheffield, Sheffield S10 2TN, UK
| | - Els Atema
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9700AB Groningen, Netherlands
| | - Raoul K Boughton
- Department of Biology, University of Memphis, Memphis, TN 38152, USA
| | - J L Brown
- Department of Biological Sciences, University of Albany, Albany, NY 12222, USA
| | | | - G Divoky
- Friends of Cooper Island, Seattle, WA 98112, USA
| | - John A Eimes
- Department of Biological Sciences, University College, Sungkyunkwan University, Suwon 16419, Korea
| | | | | | - Frans A Juola
- Department of Biology, Bucknell University, Lewisburg, PA 17837, USA
| | - David B Lank
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
| | - Hannah P Litwa
- Department of Biology, Bucknell University, Lewisburg, PA 17837, USA
| | - Ellis G A Mulder
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9700AB Groningen, Netherlands
| | | | - Kazuo Okanoya
- Department of Life Sciences, The University of Tokyo, Tokyo 113-8654, Japan
| | - Rebecca J Safran
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309, USA
| | - Stephan J Schoech
- Department of Biology, University of Memphis, Memphis, TN 38152, USA
| | - Elizabeth A Schreiber
- National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, USA
| | - Paul M Thompson
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 3FX, UK
| | - Simon Verhulst
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9700AB Groningen, Netherlands
| | | | - David W Winkler
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - Rebecca Young
- Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775, USA
| | - Carol M Vleck
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Mark F Haussmann
- Department of Biology, Bucknell University, Lewisburg, PA 17837, USA
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7
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Affiliation(s)
- Hector D Douglas
- Institute of Marine Science, University of Alaska Fairbanks, Koyukuk Drive, Fairbanks, AK, USA
- Fairbanks, AK, USA
| | - Alexander S Kitaysky
- Institute of Arctic Biology, University of Alaska Fairbanks, Koyukuk Drive, Fairbanks, AK, USA
| | - Evgenia V Kitaiskaia
- Institute of Arctic Biology, University of Alaska Fairbanks, Koyukuk Drive, Fairbanks, AK, USA
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8
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Young RC, Welcker J, Barger CP, Hatch SA, Merkling T, Kitaiskaia EV, Haussmann MF, Kitaysky AS. Effects of developmental conditions on growth, stress and telomeres in black-legged kittiwake chicks. Mol Ecol 2017; 26:3572-3584. [DOI: 10.1111/mec.14121] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 03/13/2017] [Accepted: 03/21/2017] [Indexed: 12/24/2022]
Affiliation(s)
- Rebecca C. Young
- Instituto de Ecología; UNAM; Ciudad Universitaria; Ciudad de México México
| | - Jorg Welcker
- Institute of Arctic Biology; Department of Biology and Wildlife; University of Alaska Fairbanks; Fairbanks AK USA
| | - Christopher P. Barger
- Institute of Arctic Biology; Department of Biology and Wildlife; University of Alaska Fairbanks; Fairbanks AK USA
| | - Scott A. Hatch
- Institute for Seabird Research and Conservation; Anchorage AK USA
| | - Thomas Merkling
- Université Toulouse 3 Paul Sabatier; CNRS; ENFA; UMR5174 EDB (Laboratoire Évolution & Diversité Biologique); Toulouse France
| | - Evgenia V. Kitaiskaia
- Institute of Arctic Biology; Department of Biology and Wildlife; University of Alaska Fairbanks; Fairbanks AK USA
| | | | - Alexander S. Kitaysky
- Institute of Arctic Biology; Department of Biology and Wildlife; University of Alaska Fairbanks; Fairbanks AK USA
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9
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Barger CP, Young RC, Will A, Ito M, Kitaysky AS. Resource partitioning between sympatric seabird species increases during chick‐rearing. Ecosphere 2016. [DOI: 10.1002/ecs2.1447] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Christopher P. Barger
- Department of Biology and Wildlife Institute of Arctic Biology University of Alaska Fairbanks Irving 311 Fairbanks Alaska 99775 USA
| | - Rebecca C. Young
- Department of Biology and Wildlife Institute of Arctic Biology University of Alaska Fairbanks Irving 311 Fairbanks Alaska 99775 USA
| | - Alexis Will
- Department of Biology and Wildlife Institute of Arctic Biology University of Alaska Fairbanks Irving 311 Fairbanks Alaska 99775 USA
| | - Motohiro Ito
- National Institute of Polar Research Midori‐cho 10‐3, Tachikawa‐city Tokyo 190‐8518 Japan
| | - Alexander S. Kitaysky
- Department of Biology and Wildlife Institute of Arctic Biology University of Alaska Fairbanks Irving 311 Fairbanks Alaska 99775 USA
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10
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Vincenzi S, Hatch S, Merkling T, Kitaysky AS. Carry-over effects of food supplementation on recruitment and breeding performance of long-lived seabirds. Proc Biol Sci 2016; 282:20150762. [PMID: 26180065 DOI: 10.1098/rspb.2015.0762] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Supplementation of food to wild animals is extensively applied as a conservation tool to increase local production of young. However, in long-lived migratory animals, the carry-over effects of food supplementation early in life on the subsequent recruitment of individuals into natal populations and their lifetime reproductive success are largely unknown. We examine how experimental food supplementation early in life affects: (i) recruitment as breeders of kittiwakes Rissa tridactyla born in a colony on Middleton Island (Alaska) between 1996 and 2006 (n = 1629) that bred in the same colony through 2013 (n = 235); and (ii) breeding success of individuals that have completed their life cycle at the colony (n = 56). Birds were raised in nests that were either supplemented with food (Fed) or unsupplemented (Unfed). Fledging success was higher in Fed compared with Unfed nests. After accounting for hatching rank, growth and oceanic conditions at fledging, Fed fledglings had a lower probability of recruiting as breeders in the Middleton colony than Unfed birds. The per-nest contribution of breeders was still significantly higher for Fed nests because of their higher productivity. Lifetime reproductive success of a subset of kittiwakes that thus far had completed their life cycle was not affected by the food supplementation during development. Our results cast light on the carry-over effects of early food conditions on the vital rates of long-lived animals and support food supplementation as an effective conservation strategy for long-lived seabirds.
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Affiliation(s)
- Simone Vincenzi
- Center for Stock Assessment Research, University of California Santa Cruz, 110 Shaffer Road, Santa Cruz, CA 95060, USA Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Via Ponzio 34/5, Milan 20133, Italy Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, 902 North Koyukuk Drive, Fairbanks, AK 99775, USA
| | - Scott Hatch
- US Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA Institute for Seabird Research and Conservation, 12850 Mountain Place, Anchorage, AK 99516, USA
| | - Thomas Merkling
- EDB (Laboratoire Evolution and Diversité Biologique), CNRS, UPS, ENFA, 118 Route de Narbonne, Toulouse 31062, France UMR5174, Université de Toulouse, 118 Route de Narbonne, Toulouse 31062, France
| | - Alexander S Kitaysky
- Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, 902 North Koyukuk Drive, Fairbanks, AK 99775, USA
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11
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Sato NN, Kokubun N, Yamamoto T, Watanuki Y, Kitaysky AS, Takahashi A. The jellyfish buffet: jellyfish enhance seabird foraging opportunities by concentrating prey. Biol Lett 2016; 11:rsbl.2015.0358. [PMID: 26311157 DOI: 10.1098/rsbl.2015.0358] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
High levels of jellyfish biomass have been reported in marine ecosystems around the world, but understanding of their ecological role remains in its infancy. Jellyfish are generally thought to have indirect negative impacts on higher trophic-level predators, through changes in lower trophic pathways. However, high densities of jellyfish in the water column may affect the foraging behaviour of marine predators more directly, and the effects may not always be negative. Here, we present novel observations of a diving seabird, the thick-billed murre, feeding on fish aggregating among the long tentacles of large jellyfish, by using small video loggers attached to the birds. We show that the birds encountered large jellyfish, Chrysaora melanaster, during most of their dives, commonly fed on fish associated with jellyfish, and appeared to specifically target jellyfish with a high number of fish aggregating in their tentacles, suggesting the use of jellyfish may provide significant energetic benefits to foraging murres. We conclude that jellyfish provide feeding opportunities for diving seabirds by concentrating forage fish, and that the impacts of jellyfish on marine ecosystems are more complex than previously anticipated and may be beneficial to seabirds.
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Affiliation(s)
- Nobuhiko N Sato
- Department of Polar Science, SOKENDAI (The Graduate University for Advanced Studies), Tokyo, Japan
| | - Nobuo Kokubun
- Department of Polar Science, SOKENDAI (The Graduate University for Advanced Studies), Tokyo, Japan National Institute of Polar Research, Tokyo, Japan
| | - Takashi Yamamoto
- National Institute of Polar Research, Tokyo, Japan Graduate School of Fisheries Sciences, Hokkaido University, Hokkaido, Japan
| | - Yutaka Watanuki
- Graduate School of Fisheries Sciences, Hokkaido University, Hokkaido, Japan
| | - Alexander S Kitaysky
- Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA
| | - Akinori Takahashi
- Department of Polar Science, SOKENDAI (The Graduate University for Advanced Studies), Tokyo, Japan National Institute of Polar Research, Tokyo, Japan
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12
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Benowitz-Fredericks ZM, Schultner J, Kitaysky AS. Effects of Prenatal Environment on Phenotype Are Revealed by Postnatal Challenges: Embryonic Hormone Exposure, Adrenocortical Function, and Food in Seabird Chicks. Physiol Biochem Zool 2015; 88:607-23. [PMID: 26658409 DOI: 10.1086/683259] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The interaction between prenatal environments and postnatal environments is an important source of phenotypic variability. We examined the ability of prenatal steroid exposure and postnatal energy restriction to explain adrenocortical function and fledging age in captive seabird chicks. We proposed and tested two hypotheses: (1) the strength of prenatal effects is attenuated by challenging postnatal environments (postnatal override) and (2) the strength of prenatal effects increases with the severity of postnatal challenges (postnatal reveal). We reared common murre (Uria aalge) chicks and measured prenatal exposure to corticosterone (CORT) and testosterone (T) from allantoic waste. Adrenocortical function was assessed after 10 d of ad lib. feeding and then after 5 and 10 d on controlled diets. Postnatal override predicts that prenatal steroids will explain more phenotypic variation before implementation of energy restriction; postnatal reveal predicts that the contribution of prenatal steroids will increase with duration and severity of energy restriction. Energy restriction increased secretion of baseline CORT and the adrenocortical response to the standardized stressor of handling and restraint. The ability of prenatal steroids to explain baseline CORT increased with duration of energy restriction, and for day 20 free baseline CORT, there was a significant interaction between kilojoules per day and prenatal CORT levels; severity of restriction strengthened the relationship between prenatal hormone levels and postnatal hormone levels. Both maximum CORT at day 20 and fledging age were best explained by diet treatment and day 15 or day 20 baseline CORT, respectively. Overall, prenatal CORT increased fledging age and baseline secretion of CORT, while prenatal T decreased them. However, prenatal effects on adrenocortical function were apparent only under the energy restriction conditions. Thus, we found some support for the postnatal reveal hypothesis; our results suggest that some prenatal effects on phenotype may be more likely to manifest in challenging postnatal environments.
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Affiliation(s)
- Z M Benowitz-Fredericks
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania 17837; 2Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway; 3Institute of Arctic Biology, University of Alaska, Fairbanks, Alaska 99775
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13
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Merkling T, Welcker J, Hewison AM, Hatch SA, Kitaysky AS, Speakman JR, Danchin E, Blanchard P. Identifying the selective pressures underlying offspring sex-ratio adjustments: a case study in a wild seabird. Behav Ecol 2015. [DOI: 10.1093/beheco/arv032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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14
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Young RC, Kitaysky AS, Barger CP, Dorresteijn I, Ito M, Watanuki Y. Telomere length is a strong predictor of foraging behavior in a long-lived seabird. Ecosphere 2015. [DOI: 10.1890/es14-00345.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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15
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Welcker J, Speakman JR, Elliott KH, Hatch SA, Kitaysky AS. Resting and daily energy expenditures during reproduction are adjusted in opposite directions in free‐living birds. Funct Ecol 2014. [DOI: 10.1111/1365-2435.12321] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jorg Welcker
- Norwegian Polar Institute Fram Centre N‐9296 Tromsø Norway
- Institute of Arctic Biology University of Alaska Fairbanks Irving 311Fairbanks Alaska 99775 USA
| | - John R. Speakman
- Institute of Biological and Environmental Sciences University of AberdeenTillydrone Avenue Aberdeen AB24 2TZ UK
- State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences 1 West Beichen RoadChaoyang Beijing China
| | - Kyle H. Elliott
- Department of Biological Sciences University of Manitoba Winnipeg ManitobaR3T 2N2 Canada
| | - Scott A. Hatch
- Alaska Science Center U.S. Geological Survey 4210 University Drive Anchorage Alaska99508 USA
| | - Alexander S. Kitaysky
- Institute of Arctic Biology University of Alaska Fairbanks Irving 311Fairbanks Alaska 99775 USA
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16
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Will AP, Suzuki Y, Elliott KH, Hatch SA, Watanuki Y, Kitaysky AS. Feather corticosterone reveals developmental stress in seabirds. ACTA ACUST UNITED AC 2014; 217:2371-6. [PMID: 24744418 DOI: 10.1242/jeb.098533] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In nest-bound avian offspring, food shortages typically trigger a release of the stress hormone corticosterone (CORT). Recent studies indicate that CORT is passively deposited in the tissue of growing feathers and thus may provide an integrated measure of stress incurred during development in the nest. The current hypothesis predicts that, assuming a constant rate of feather growth, elevated CORT circulating in the blood corresponds to higher levels of CORT in feather tissue, but experimental evidence for nutritionally stressed chicks is lacking. Here, we examined how food limitation affects feather CORT content in the rhinoceros auklet (Cerorhinca moncerata). We (i) used captive chicks reared on control versus restricted diets, and (ii) applied this technique to free-living chicks with unknown nutritional histories that fledged at three separate colonies. We found that (i) feather growth was not affected by experimentally induced nutritional stress; (ii) captive chicks raised on a restricted diet had higher levels of CORT in their primary feathers; (iii) feather CORT deposition is a sensitive method of detecting nutritional stress; and (iv) free-living fledglings from the colony with poor reproductive performance had higher CORT in their primary feathers. We conclude that feather CORT is a sensitive integrated measure revealing the temporal dynamics of food limitations experienced by rhinoceros auklet nestlings. The use of feather CORT may be a powerful endocrine tool in ecological and evolutionary studies of bird species with similar preferential allocation of limited resources to feather development.
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Affiliation(s)
- Alexis P Will
- Institute of Arctic Biology, 311 Irving 1, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Yuya Suzuki
- Graduate School of Fisheries Sciences, Hokkaido University, Minato-cho 3-1-1, Hakodate, 041-8611, Japan
| | - Kyle H Elliott
- Department of Zoology, Z320 Duff Roblin Building, University of Manitoba, Winnipeg, MB, Canada, R3T 2N2
| | - Scott A Hatch
- Institute for Seabird Research and Conservation, 12850 Mountain Place, Anchorage, AK 99516, USA
| | - Yutaka Watanuki
- Graduate School of Fisheries Sciences, Hokkaido University, Minato-cho 3-1-1, Hakodate, 041-8611, Japan
| | - Alexander S Kitaysky
- Institute of Arctic Biology, 311 Irving 1, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
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17
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Abstract
Changes in telomere length are believed to reflect changes in physiological state and life expectancy in animals. However, much remains unknown about the determinants of telomere dynamics in wild populations, and specifically the influence of conditions during highly mobile life-history stages, for example migration. We tested whether telomere dynamics were associated with migratory behaviour and/or with stress during reproduction in free-living seabirds. We induced short-term stress during reproduction in chick-rearing, black-legged kittiwakes (Rissa tridactyla), tracked winter migration with geolocators and measured telomere length before and after winter migration. We found that time spent at wintering grounds correlated with reduced telomere loss, while stress during reproduction accelerated telomere shortening. Our results suggest that different life-history stages interact to influence telomere length, and that migratory patterns may be important determinants of variation in an individual's telomere dynamics.
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Affiliation(s)
- Jannik Schultner
- Department of Biology, Norwegian University of Science and Technology, , Natural Sciences Building, Trondheim 7491, Norway
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18
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Schultner J, Kitaysky AS, Gabrielsen GW, Hatch SA, Bech C. Differential reproductive responses to stress reveal the role of life-history strategies within a species. Proc Biol Sci 2013; 280:20132090. [PMID: 24089339 DOI: 10.1098/rspb.2013.2090] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Life-history strategies describe that 'slow'- in contrast to 'fast'-living species allocate resources cautiously towards reproduction to enhance survival. Recent evidence suggests that variation in strategies exists not only among species but also among populations of the same species. Here, we examined the effect of experimentally induced stress on resource allocation of breeding seabirds in two populations with contrasting life-history strategies: slow-living Pacific and fast-living Atlantic black-legged kittiwakes. We tested the hypothesis that reproductive responses in kittiwakes under stress reflect their life-history strategies. We predicted that in response to stress, Pacific kittiwakes reduce investment in reproduction compared with Atlantic kittiwakes. We exposed chick-rearing kittiwakes to a short-term (3-day) period of increased exogenous corticosterone (CORT), a hormone that is released during food shortages. We examined changes in baseline CORT levels, parental care and effects on offspring. We found that kittiwakes from the two populations invested differently in offspring when facing stress. In response to elevated CORT, Pacific kittiwakes reduced nest attendance and deserted offspring more readily than Atlantic kittiwakes. We observed lower chick growth, a higher stress response in offspring and lower reproductive success in response to CORT implantation in Pacific kittiwakes, whereas the opposite occurred in the Atlantic. Our findings support the hypothesis that life-history strategies predict short-term responses of individuals to stress within a species. We conclude that behaviour and physiology under stress are consistent with trade-off priorities as predicted by life-history theory. We encourage future studies to consider the pivotal role of life-history strategies when interpreting inter-population differences of animal responses to stressful environmental events.
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Affiliation(s)
- J Schultner
- Department of Biology, Norwegian University of Science and Technology, , Trondheim, Norway, Institute of Arctic Biology, University of Alaska Fairbanks, , Fairbanks, AK, USA, Norwegian Polar Institute, , Tromsø, Norway, US Geological Survey, Anchorage Science Center, , Anchorage, AK, USA, Institute for Seabird Research and Conservation, , Anchorage, AK, USA
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19
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Young RC, Kitaysky AS, Haussmann MF, Descamps S, Orben RA, Elliott KH, Gaston AJ. Age, sex, and telomere dynamics in a long-lived seabird with male-biased parental care. PLoS One 2013; 8:e74931. [PMID: 24023967 PMCID: PMC3762738 DOI: 10.1371/journal.pone.0074931] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 08/07/2013] [Indexed: 11/24/2022] Open
Abstract
The examination of telomere dynamics is a recent technique in ecology for assessing physiological state and age-related traits from individuals of unknown age. Telomeres shorten with age in most species and are expected to reflect physiological state, reproductive investment, and chronological age. Loss of telomere length is used as an indicator of biological aging, as this detrimental deterioration is associated with lowered survival. Lifespan dimorphism and more rapid senescence in the larger, shorter-lived sex are predicted in species with sexual size dimorphism, however, little is known about the effects of behavioral dimorphism on senescence and life history traits in species with sexual monomorphism. Here we compare telomere dynamics of thick-billed murres (Urialomvia), a species with male-biased parental care, in two ways: 1) cross-sectionally in birds of known-age (0-28 years) from one colony and 2) longitudinally in birds from four colonies. Telomere dynamics are compared using three measures: the telomere restriction fragment (TRF), a lower window of TRF (TOE), and qPCR. All showed age-related shortening of telomeres, but the TRF measure also indicated that adult female murres have shorter telomere length than adult males, consistent with sex-specific patterns of ageing. Adult males had longer telomeres than adult females on all colonies examined, but chick telomere length did not differ by sex. Additionally, inter-annual telomere changes may be related to environmental conditions; birds from a potentially low quality colony lost telomeres, while those at more hospitable colonies maintained telomere length. We conclude that sex-specific patterns of telomere loss exist in the sexually monomorphic thick-billed murre but are likely to occur between fledging and recruitment. Longer telomeres in males may be related to their homogamous sex chromosomes (ZZ) or to selection for longer life in the care-giving sex. Environmental conditions appeared to be the primary drivers of annual changes in adult birds.
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Affiliation(s)
- Rebecca C. Young
- Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
| | - Alexander S. Kitaysky
- Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
| | - Mark F. Haussmann
- Biology Department, Bucknell University; Lewisburg, Pennyslvania, United States of America
| | | | - Rachael A. Orben
- Department of Ocean Sciences, Long Marine Laboratory, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Kyle H. Elliott
- Department of Biological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Anthony J. Gaston
- Department of Biological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
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20
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Benowitz-Fredericks ZM, Kitaysky AS, Welcker J, Hatch SA. Effects of food availability on yolk androgen deposition in the black-legged kittiwake (Rissa tridactyla), a seabird with facultative brood reduction. PLoS One 2013; 8:e62949. [PMID: 23675443 PMCID: PMC3652864 DOI: 10.1371/journal.pone.0062949] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 03/26/2013] [Indexed: 11/19/2022] Open
Abstract
In birds with facultative brood reduction, survival of the junior chick is thought to be regulated primarily by food availability. In black-legged kittiwakes (Rissa tridactyla) where parents and chicks are provided with unlimited access to supplemental food during the breeding season, brood reduction still occurs and varies interannually. Survival of the junior chick is therefore affected by factors in addition to the amount of food directly available to them. Maternally deposited yolk androgens affect competitive dynamics within a brood, and may be one of the mechanisms by which mothers mediate brood reduction in response to a suite of environmental and physiological cues. The goal of this study was to determine whether food supplementation during the pre-lay period affected patterns of yolk androgen deposition in free-living kittiwakes in two years (2003 and 2004) that varied in natural food availability. Chick survival was measured concurrently in other nests where eggs were not collected. In both years, supplemental feeding increased female investment in eggs by increasing egg mass. First-laid ("A") eggs were heavier but contained less testosterone and androstenedione than second-laid ("B") eggs across years and treatments. Yolk testosterone was higher in 2003 (the year with higher B chick survival) across treatments. The difference in yolk testosterone levels between eggs within a clutch varied among years and treatments such that it was relatively small when B chick experienced the lowest and the highest survival probabilities, and increased with intermediate B chick survival probabilities. The magnitude of testosterone asymmetry in a clutch may allow females to optimize fitness by either predisposing a brood for reduction or facilitating survival of younger chicks.
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21
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Welcker J, Chastel O, Gabrielsen GW, Guillaumin J, Kitaysky AS, Speakman JR, Tremblay Y, Bech C. Thyroid hormones correlate with basal metabolic rate but not field metabolic rate in a wild bird species. PLoS One 2013; 8:e56229. [PMID: 23437096 PMCID: PMC3577771 DOI: 10.1371/journal.pone.0056229] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 01/07/2013] [Indexed: 11/18/2022] Open
Abstract
Thyroid hormones (TH) are known to stimulate in vitro oxygen consumption of tissues in mammals and birds. Hence, in many laboratory studies a positive relationship between TH concentrations and basal metabolic rate (BMR) has been demonstrated whereas evidence from species in the wild is scarce. Even though basal and field metabolic rates (FMR) are often thought to be intrinsically linked it is still unknown whether a relationship between TH and FMR exists. Here we determine the relationship between the primary thyroid hormone triiodothyronine (T3) with both BMR and FMR in a wild bird species, the black-legged kittiwake (Rissa tridactyla). As predicted we found a strong and positive relationship between plasma concentrations of T3 and both BMR and mass-independent BMR with coefficients of determination ranging from 0.36 to 0.60. In contrast there was no association of T3 levels with either whole-body or mass-independent FMR (R(2) =0.06 and 0.02, respectively). In accordance with in vitro studies our data suggests that TH play an important role in modulating BMR and may serve as a proxy for basal metabolism in wild birds. However, the lack of a relationship between TH and FMR indicates that levels of physical activity in kittiwakes are largely independent of TH concentrations and support recent studies that cast doubt on a direct linkage between BMR and FMR.
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22
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Schultner J, Kitaysky AS, Welcker J, Hatch S. Fat or lean: adjustment of endogenous energy stores to predictable and unpredictable changes in allostatic load. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.02058.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Alexander S. Kitaysky
- Institute of Arctic Biology; University of Alaska Fairbanks; 311 Irving I, Fairbanks, AK; 99775; USA
| | | | - Scott Hatch
- US Geological Survey; Alaska Science Center; 4210 University Drive, Anchorage, AK; 99508; USA
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Drovetski SV, Kitaysky AS, Mode NA, Zink RM, Iqbal U, Barger C. mtDNA haplotypes differ in their probability of being eliminated by a mass die-off in an abundant seabird. Heredity (Edinb) 2012; 109:29-33. [PMID: 22354113 DOI: 10.1038/hdy.2012.4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
In this study, we take advantage of a natural experiment--a 2004 mass die-off of the Common Murre in Alaska to determine whether closely related mtDNA haplotypes differ in their probability of being eliminated during such a short term but a marked event removing hundreds of thousands of individuals. We sequenced complete mtDNA ND2 gene (1041 bp) for 168 Common Murres sampled from seven breeding colonies across Alaska before the 2004 die-off and 127 dead murres washed ashore during the die-off. We found little mtDNA variation and lack of geographical structuring among the seven Common Murre breeding colonies in Alaska. A comparison of the single-dominant mtDNA haplotype's frequency between live murres sampled on breeding colonies before the die-off (73.2%; 95% confidence interval 66.3-79.9%) and dead murres sampled during the die-off (59.1%; 95% confidence interval 50.4-67.4%; Fisher's exact P=0.01) showed that carriers of the dominant haplotype were significantly less likely to die than carriers of other haplotypes. At the same time, the ratio of non-synonymous to synonymous substitutions did not differ between live (10:35) and dead birds (18:34; Fisher's exact P=0.26), indicating that non-synonymous substitutions were as likely to be eliminated as synonymous substitutions. These results are consistent with the possibility of positive selection on the dominant mtDNA haplotype during the die-off.
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Affiliation(s)
- S V Drovetski
- Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Vairão, Portugal.
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24
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Abstract
Dietary segregation is essential for the coexistence of closely related species of animals. However, little is known about how changes in availability of food resources might affect trophic interactions of wild animals breeding in sympatry. Here, we examined how interannual variations in relative food availability (as reflected in blood levels of stress hormone corticosterone, CORT) affect food partitioning (assessed via a comparison of stable isotope δ(15)N and δ(13)C ratios of blood) between the common murre (Uria aalge) and thick-billed murre (Uria lomvia), breeding on a single colony in the Bering Sea. During a 6-year study, CORT varied among years but not between species, whereas stable isotope ratios varied among years and between species. Isotopic distance between species increased with increasing CORT. These results indicate that, when food was not limiting, both species relied on similar food resources. As foraging conditions deteriorated, murres diverged in their diets. We conclude that the degree of dietary segregation between Uria spp. varies with changes in the availability of food and is greatest during food shortages.
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Affiliation(s)
- Christopher P Barger
- Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.
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Harding AMA, Welcker J, Steen H, Hamer KC, Kitaysky AS, Fort J, Talbot SL, Cornick LA, Karnovsky NJ, Gabrielsen GW, Grémillet D. Adverse foraging conditions may impact body mass and survival of a high Arctic seabird. Oecologia 2011; 167:49-59. [DOI: 10.1007/s00442-011-1971-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Accepted: 02/10/2011] [Indexed: 02/07/2023]
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26
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Kitaysky AS, Piatt JF, Hatch SA, Kitaiskaia EV, Benowitz-Fredericks ZM, Shultz MT, Wingfield JC. Food availability and population processes: severity of nutritional stress during reproduction predicts survival of long-lived seabirds. Funct Ecol 2009. [DOI: 10.1111/j.1365-2435.2009.01679.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Welcker J, Harding AMA, Kitaysky AS, Speakman JR, Gabrielsen GW. Daily energy expenditure increases in response to low nutritional stress in an Arctic-breeding seabird with no effect on mortality. Funct Ecol 2009. [DOI: 10.1111/j.1365-2435.2009.01585.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Harding AM, Kitaysky AS, Hall ME, Welcker J, Karnovsky NJ, Talbot SL, Hamer KC, Grémillet D. Flexibility in the parental effort of an Arctic-breeding seabird. Funct Ecol 2009. [DOI: 10.1111/j.1365-2435.2008.01488.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Addison B, Kitaysky AS, Hipfner JM. Sex allocation in a monomorphic seabird with a single-egg clutch: test of the environment, mate quality, and female condition hypotheses. Behav Ecol Sociobiol 2008. [DOI: 10.1007/s00265-008-0643-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Addison B, Benowitz-Fredericks ZM, Hipfner JM, Kitaysky AS. Are yolk androgens adjusted to environmental conditions? A test in two seabirds that lay single-egg clutches. Gen Comp Endocrinol 2008; 158:5-9. [PMID: 18577385 DOI: 10.1016/j.ygcen.2008.05.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Revised: 03/12/2008] [Accepted: 05/30/2008] [Indexed: 12/17/2022]
Abstract
It is widely believed that female birds strategically allocate androgens to yolk in the manner that best equips offspring for feeding conditions during their development. Because most avian studies have focused on multi-egg clutch species, and interpreted results within the framework of sibling competition, we still know little about how yolk androgens might be allocated in direct response to environmental conditions. Most oceanic birds are long-lived and lay single-egg clutches, and their breeding success is tightly linked to highly variable marine production. That combination: a variable breeding environment, long lives, and single-egg clutches, makes oceanic birds good subjects to test hypotheses about yolk androgen allocation strategies. We measured concentrations of two yolk androgens, androstenedione (A4) and testosterone (T), in the single-egg clutches laid by early-laying Cassin's (Ptychoramphus aleuticus) and rhinoceros (Cerorhinca monocerata) auklets at Triangle Island, British Columbia, Canada, in 2002-2004. Environmental conditions including sea-surface temperatures and the timing and intensity of marine primary production varied over the 3 years, and in response, both the timing and success of seabird breeding varied. As in other avian species, concentrations of A4 and T varied markedly among individual eggs in both species (by factors of 3-8), yet contrary to expectation, little of the variation could be attributed to year effects. The high interindividual variation and the lack of interannual variation suggest a non-adaptive explanation for yolk androgen deposition relative to environmental conditions in these species.
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Affiliation(s)
- BriAnne Addison
- Centre for Wildlife Ecology, Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada V5A 1S6.
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31
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Douglas HD, Kitaysky AS, Kitaiskaia EV. Seasonal covariation in progesterone and odorant emissions among breeding crested auklets (Aethia cristatella). Horm Behav 2008; 54:325-9. [PMID: 18445496 DOI: 10.1016/j.yhbeh.2008.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2007] [Revised: 02/04/2008] [Accepted: 03/03/2008] [Indexed: 11/16/2022]
Abstract
Crested auklets emit a citrus-like odorant that is seasonally modulated, suggesting that it is a secondary sexual trait. We hypothesized that expression of the chemical odorant is facilitated by steroid hormones, similar other secondary sexual traits in birds. Therefore we examined variation in concentrations of hormones in blood plasma and odor production during incubation and early chick rearing. A novel method was used to obtain and measure chemical emissions of crested auklets. Blood plasma samples were analyzed by radioimmunoassay. Progesterone was detected in all birds, and it varied during the breeding season. Octanal emissions covaried with progesterone levels in males but not in females. No seasonal patterns were detected in testosterone, estrogen or DHT, and these hormones were not detected in all breeding adults. Covariance of progesterone and octanal emissions in males suggests there could be at least an indirect relationship between odor emissions and steroid hormones in this species. Thus expression of the citrus-like odorant of crested auklets, like other secondary sexual traits in birds, could be regulated by steroid hormones.
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Affiliation(s)
- Hector D Douglas
- Biology Department, Kuskokwim Campus, University of Alaska Fairbanks, Bethel, Alaska 99559, USA.
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32
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Williams CT, Kitaysky AS, Kettle AB, Buck CL. Corticosterone levels of tufted puffins vary with breeding stage, body condition index, and reproductive performance. Gen Comp Endocrinol 2008; 158:29-35. [PMID: 18547575 DOI: 10.1016/j.ygcen.2008.04.018] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 03/15/2008] [Accepted: 04/30/2008] [Indexed: 11/18/2022]
Abstract
Corticosterone (CORT) levels in free-living animals are seasonally modulated and vary with environmental conditions. Although most studies measure total CORT concentrations, levels of corticosteroid binding globulin (CBG) may also be modulated, thus altering the concentration of CORT available for diffusion into tissues (free CORT). We investigated the seasonal dynamics of CBG, total CORT, and free CORT in breeding tufted puffins (Fratercula cirrhata) during 2 years characterized by high rates of nestling growth and survival. We then compared concentrations of total CORT in this population to levels in chick-rearing puffins at another colony during 2 years with low productivity. At the high productivity colony, levels of CBG, total baseline CORT, free baseline CORT, and total maximum CORT were all higher prior to egg-laying than during late incubation and late chick-rearing. Levels of CBG were positively correlated with body condition index (BCI) and free baseline CORT was negatively correlated with BCI. Total baseline levels of CORT during chick-rearing were two to four times higher at the colony with low rates of nestling growth and survival. Our results demonstrate the need for long-term datasets to disentangle seasonal trends in CORT levels from trends driven by changes in environmental conditions. Given the negative effects associated with chronic elevation of CORT, our results indicate the cost of reproduction may be higher during years characterized by low productivity.
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Affiliation(s)
- Cory T Williams
- School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
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Williams CT, Buck CL, Sears J, Kitaysky AS. Effects of nutritional restriction on nitrogen and carbon stable isotopes in growing seabirds. Oecologia 2007; 153:11-8. [PMID: 17406905 DOI: 10.1007/s00442-007-0717-z] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Accepted: 03/05/2007] [Indexed: 10/23/2022]
Abstract
When using stable isotopes as dietary tracers it is essential to consider effects of nutritional state on isotopic fractionation. While starvation is known to induce enrichment of (15)N in body tissues, effects of moderate food restriction on isotope signatures have rarely been tested. We conducted two experiments to investigate effects of a 50-55% reduction in food intake on delta(15)N and delta(13)C values in blood cells and whole blood of tufted puffin chicks, a species that exhibits a variety of adaptive responses to nutritional deficits. We found that blood from puffin chicks fed ad libitum became enriched in (15)N and (13)C compared to food-restricted chicks. Our results show that (15)N enrichment is not always associated with food deprivation and argue effects of growth on diet-tissue fractionation of nitrogen stable isotopes (Delta(15)N) need to be considered in stable isotope studies. The decrease in delta(13)C of whole blood and blood cells in restricted birds is likely due to incorporation of carbon from (13)C-depleted lipids into proteins. Effects of nutritional restriction on delta(15)N and delta(13)C values were relatively small in both experiments (delta(15)N: 0.77 and 0.41 per thousand, delta(13)C: 0.20 and 0.25 per thousand) compared to effects of ecological processes, indicating physiological effects do not preclude the use of carbon and nitrogen stable isotopes in studies of seabird ecology. Nevertheless, our results demonstrate that physiological processes affect nitrogen and carbon stable isotopes in growing birds and we caution isotope ecologists to consider these effects to avoid drawing spurious conclusions.
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Affiliation(s)
- Cory T Williams
- School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.
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34
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Pravosudov VV, Kitaysky AS, Omanska A. The relationship between migratory behaviour, memory and the hippocampus: an intraspecific comparison. Proc Biol Sci 2006; 273:2641-9. [PMID: 17002950 PMCID: PMC1635458 DOI: 10.1098/rspb.2006.3624] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
It has been hypothesized that memory-demanding ecological conditions might result in enhanced memory and an enlarged hippocampus, an area of the brain involved in memory processing, either via extensive memory experience or through evolutionary changes. Avian migration appears to represent one of such memory-demanding ecological conditions. We compared two subspecies of the white-crowned sparrow: migratory Zonotrichia leucophrys gambelii and non-migratory Z. l. nuttalli. Compared to non-migratory Z. l. nuttalli, migratory Z. l. gambelii showed better memory performance on spatial one-trial associative learning tasks and had more hippocampal neurons. Migratory subspecies also had larger hippocampi relative to the remainder of the telencephalon but not relative to body mass. In adults, the differences between migratory and non-migratory sparrows were especially pronounced in the right hippocampus. Juvenile migratory Z. l. gambelii had relatively larger hippocampal volume compared to juvenile non-migratory Z. l. nuttalli. Adult migratory Z. l. gambelii had more neurons in their right hippocampus compared to juveniles but such differences were not found in non-migratory Z. l. nuttalli. Our results suggest that migratory behaviour might be related to enhanced spatial memory and an enlarged hippocampus with more neurons, and that differences in the hippocampus between migratory and non-migratory sparrows might be experience-dependent. Furthermore, for the first time our results suggest that the right hippocampus, which encodes global spatial information, might be involved in migratory behaviour.
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Abstract
A climatic regime shift during the mid-1970s in the North Pacific resulted in decreased availability of lipid-rich fish to seabirds and was followed by a dramatic decline in number of kittiwakes breeding on the Pribilof Islands. Although production of chicks in the mid-1970s was adequate to sustain kittiwake populations in the early 1980s, the disappearance of birds from breeding colonies apparently exceeded recruitment. No mechanism has been proposed to explain why recruitment would differ among fledglings fed lipid-rich or lipid-poor fish during development. Here we show that diets low in lipids induce nutritional stress and impair cognitive abilities in young red-legged kittiwakes, Rissa brevirostris. Specifically, growth retardation, increased secretion of stress hormones and inferior ability to associate food distribution with visual cues were observed in individuals fed lipid-poor diets. We conclude that lipid-poor diets during development affect the quality of young seabirds, which is likely to result in their increased mortality and low recruitment.
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Affiliation(s)
- Alexander S Kitaysky
- Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska Fairbanks, Irving 311, Fairbanks, AK 99775, USA.
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36
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Abstract
Recent studies examining patterns and consequences of variation in maternally deposited steroids in avian egg yolk have demonstrated that these maternal hormones can have dramatic effects on chick phenotypes. However, maternal steroids are not the only source for avian embryos, which activate endocrine axes relatively early in development and are capable of producing substantial amounts of endogenous steroids. Although organizational effects of steroids have been demonstrated, the interactions between steroids from yolk and endogenous production have not been addressed. Steroids in the yolk are likely to alter development of the embryo's endocrine axes. The ability to assess total steroid exposure in ovo in a nonlethal fashion would improve our understanding of these interactions and help elucidate the mechanisms by which maternal steroids alter chick phenotype. Steroid levels in allantoic waste provide a cumulative measure of steroids excreted in ovo and may prove to be a useful tool. We present data from semiprecocial seabirds, common murres, demonstrating the presence of detectable steroids in allantoic waste and suggesting that some reflect differences in timing of hatching and may provide information about aspects of chick phenotype.
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Pravosudov VV, Kitaysky AS. Effects of nutritional restrictions during post-hatching development on adrenocortical function in western scrub-jays (Aphelocoma californica). Gen Comp Endocrinol 2006; 145:25-31. [PMID: 16102756 DOI: 10.1016/j.ygcen.2005.06.011] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Revised: 06/16/2005] [Accepted: 06/29/2005] [Indexed: 11/16/2022]
Abstract
Altricial birds grow rapidly during post-hatching period and are developmentally sensitive to variations in food supply. Limited food results in elevated corticosterone levels in chicks of semi-precocial birds but it is not clear whether altricial songbirds show similar adrenocortical stress response to nutritional restrictions during early development. It is also unknown how nutritional stress during early development affects the adrenocortical function later in life in altricial birds which show tremendous variation in the magnitude of adrenocortical stress response. Using western scrub-jays (Aphelocoma californica), we experimentally demonstrated that moderate food restrictions (65% of ad libitum) during post-hatching development caused significant elevation of baseline corticosterone levels in nest-bound chicks. Compared to controls, 1-year-old scrub-jays that experienced nutritional deficits during post-hatching development also showed a marginally significant trend to have stronger adrenocortical stress response and significantly greater degree of fluctuating asymmetry in bone and feather measurements. Thus, our results demonstrated that developing altricial birds show adrenocortical response to nutritional deficits, which might produce long-term changes in responsiveness of the adrenal system. Our study suggests that baseline corticosterone levels are a good indicator of physiological conditions of developing birds and that individual variance in adrenocortical stress response commonly observed in many species might, at least in part, be explained by environmental conditions during early development. Considering that nutritional restrictions during early development are linked to many permanent changes including impaired cognitive abilities, corticosterone levels in developing young might be a reliable predictor of their future fitness.
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Kitaysky AS, Romano MD, Piatt JF, Wingfield JC, Kikuchi M. The adrenocortical response of tufted puffin chicks to nutritional deficits. Horm Behav 2005; 47:606-19. [PMID: 15811363 DOI: 10.1016/j.yhbeh.2005.01.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2004] [Revised: 12/28/2004] [Accepted: 01/05/2005] [Indexed: 01/09/2023]
Abstract
In several seabirds, nutritional state of a nest-bound chick is negatively correlated with the activity of its hypothalamus-pituitary-adrenal (HPA) axis. Increased corticosterone (cort) secretion has been shown to facilitate changes in behavior that allow hungry chicks to obtain more food from parents. However, if parents are not willing/able to buffer their young from temporary food shortages, increased cort secretion could be detrimental to undernourished chicks. In a system where parents are insensitive to chick demands, low benefits and high costs of activation of the HPA-axis in hungry chicks should lead to a disassociation of the nutritional state of the young and the activity of its HPA-axis. We tested this novel hypothesis for the tufted puffin (Fratercula cirrhata), a seabird with intermittent provisioning of a nest-bound semi-precocial chick. We examined the HPA-axis activity of captive chicks exposed to the following: (1) a short-term (24 h) food deprivation; and (2) an array of prolonged (3 weeks) restrictions in feeding regimens. We found that in response to a short-term food deprivation chicks decreased baseline levels of cort and thyroid hormones. In response to prolonged restrictions, food-limited chicks exhibited signs of nutritional deficit: they had lower body mass, endogenous lipid reserves, and thyroid hormone titers compared to chicks fed ad libitum. However, baseline and maximum acute stress-induced levels of cort were also lower in food-restricted chicks compared to those of chicks fed ad libitum. These results support a major prediction of the study hypothesis that puffin chicks suppress HPA-axis activity in response to short- and long-term nutritional deficits. This physiological adaptation may allow a chick to extend its development in the nest, while eluding detrimental effects of chronic cort elevation.
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Affiliation(s)
- Alexander S Kitaysky
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.
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Williams TD, Kitaysky AS, Vézina F. Individual variation in plasma estradiol-17beta and androgen levels during egg formation in the European starling Sturnus vulgaris: implications for regulation of yolk steroids. Gen Comp Endocrinol 2004; 136:346-52. [PMID: 15081834 DOI: 10.1016/j.ygcen.2004.01.010] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2003] [Revised: 01/21/2004] [Accepted: 01/26/2004] [Indexed: 11/21/2022]
Abstract
While it is clear that maternal transfer of steroids to egg yolk can have significant effects on offspring phenotype, an unresolved question is whether females can facultatively adjust yolk hormone levels independently of their own plasma levels or whether yolk steroid levels are simply a direct consequence of temporal variation in the female's hormonal status. In part, this is because we lack detailed information about the day-to-day pattern of changes in plasma hormone levels during the laying cycle for non-domesticated birds. Here, we describe changes in plasma estradiol-17beta (E2) and androgens, throughout laying in relation to specific stages of ovarian follicular development in the European starling (Sturnus vulgaris). Plasma E2 levels increased rapidly from the onset of rapid yolk development (RYD) to reach maximum levels in birds with a complete follicle hierarchy (> or = 4 yolky follicles). However, levels decreased linearly throughout the later stages of follicle development returning to pre-breeding values before the final yolky follicle was ovulated. In females with > or = 4 yolky follicles there was 10-fold variation in plasma E2 levels among individual females, but this was not related to plasma levels of the main yolk precursor vitellogenin or to the total mass of yolky follicles developing at the time of blood sampling. In contrast to E2, plasma androgen levels showed only a very gradual linear decline throughout the laying cycle from pre-RYD to clutch completion. Furthermore, androgen levels showed less individual variability: 4-fold variation among females with > or = 4 yolky follicles, although this was also independent of our measures of reproductive function. Data on inter- and intra-individual variation in female hormone levels are important to set-up a priori predictions for, and interpretation of, studies of yolk hormone levels.
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Affiliation(s)
- T D Williams
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada.
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Pravosudov VV, Kitaysky AS, Wingfield JC, Clayton NS. No latitudinal differences in adrenocortical stress response in wintering black-capped chickadees (Poecile atricapilla). Comp Biochem Physiol A Mol Integr Physiol 2004; 137:95-103. [PMID: 14720595 DOI: 10.1016/s1095-6433(03)00264-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Birds respond to deterioration in environmental conditions by elevating their corticosterone levels, which can enhance their survival. It is less clear if animals constantly living in energetically challenging environment show similar increases in adrenocortical function. Previous work has demonstrated that under controlled conditions black-capped chickadees (Poecile atricapilla) from northern latitudes cache more food and perform better on spatial memory tasks than their southern conspecifics. As elevated levels of corticosterone have been shown previously to correlate with spatial memory performance in chickadees, this study aimed to investigate whether black-capped chickadees from northern latitudes have elevated baseline levels of corticosterone and/or a stronger adrenocortical stress response than their southern conspecifics, irrespective of their immediate environment. We found no differences between Alaskan and Colorado chickadees maintained under identical conditions for 3 months in either baseline levels of corticosterone or maximum levels of corticosterone achieved during the stress response. Baseline corticosterone levels were negatively correlated with relative body mass across both groups of birds. Our results suggest that the population differences in food catching behavior and spatial memory were not related to differences in corticosterone levels. We conclude that many reported population differences in baseline levels and in strength of adrenocortical stress response may often reflect differences in local environmental conditions rather than population-specific physiological traits.
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Affiliation(s)
- Vladimir V Pravosudov
- Department of Psychology, University of California Davis, Young Hall, CA 95616-8519, USA.
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Abstract
Seabird chicks respond to food shortages by increasing corticosterone (cort) secretion, which is probably associated with fitness benefits and costs. To examine this, we experimentally increased levels of circulating cort in captive black-legged kittiwake chicks fed ad libitum. We found that cort-implanted chicks begged more frequently and were more aggressive compared to controls. These behavioral modifications must be beneficial to chicks as they facilitate acquisition of food from the parents and might trigger brood reduction and reduced competition for food. Cort-implanted chicks also increased food intake; however, their growth rates were similar to controls. To examine the costs of chronically increased circulating levels of cort, we removed cort implants and, after a 10-day recovery period, tested cognitive abilities of young kittiwakes. We found that the ability of kittiwakes to associate a visual cue with the presence of food in a choice situation was compromised by the experimental elevation of cort during development. To examine the long-term costs of increased levels of cort, 8 months later we tested the performance of the same individuals in a spatial task requiring them to make a detour around a barrier in order to escape from an enclosure. Individuals treated with cort during development took significantly more time to solve this task compared to controls. The results of this study suggest that the adrenocortical response of a developing bird to environmental stressors is associated with both benefits (increased food intake, foraging behavior, and aggression) and costs (low growth efficiency and compromised cognitive abilities later in life). This provides an evolutionary framework for relating juvenile physiological traits to fitness of birds in subsequent life-history stages.
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Affiliation(s)
- A S Kitaysky
- Department of Zoology, 24 Kincaid Hall, Box 351800, University of Washington, Seattle, WA 98195, USA.
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Pravosudov VV, Kitaysky AS, Saldanha CJ, Wingfield JC, Clayton NS. The effect of photoperiod on adrenocortical stress response in mountain chickadees (Poecile gambeli). Gen Comp Endocrinol 2002; 126:242-8. [PMID: 12030780 DOI: 10.1006/gcen.2002.7798] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Birds respond to environmental changes by modulating their levels of plasma corticosterone, a stress hormone produced by the adrenal glands. Baseline levels of corticosterone and the magnitude of adrenocortical response to acute stress are known to vary seasonally. Photoperiod is one of several potential factors which could affect the seasonal modulation of corticosterone secretion. In this study, we examined the effects of photoperiod on baseline and acute-stress-induced levels of corticosterone in adult mountain chickadees (Poecile gambeli). We exposed 20 mountain chickadees to short days (8L:16D h) for 60 days, after which half of the chickadees were switched to long days (14L:10D h). We collected blood samples from both groups 33 days after the switching. Our results showed that photoperiod had no significant effect either on baseline levels of corticosterone or on the maximum levels reached during the adrenocortical response to acute stress. However, photoperiod had a significant effect on the way that chickadees responded to acute stress: birds maintained on long days reached significantly higher levels of corticosterone between 5 and 20 min after capture than birds maintained on short days, which reached their maximum levels of corticosterone between 20 and 50 min. Females reached significantly higher levels of corticosterone than males in response to acute stress. Our results suggest that factors other than photoperiod are responsible for the observed seasonal changes in baseline levels of corticosterone, whereas photoperiod is directly involved in regulation of adrenocortical stress response.
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Affiliation(s)
- Vladimir V Pravosudov
- Section of Neurobiology, Physiology, and Behavior, University of California-Davis, Davis, CA 95616, USA
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Kitaysky AS, Kitaiskaia EV, Wingfield JC, Piatt JF. Dietary restriction causes chronic elevation of corticosterone and enhances stress response in red-legged kittiwake chicks. J Comp Physiol B 2001; 171:701-9. [PMID: 11765979 DOI: 10.1007/s003600100230] [Citation(s) in RCA: 213] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Release of corticosterone in hungry kittiwake chicks facilitates begging and allows them to restore depleted energy reserves by increasing parental food provisioning. However, in order to avoid detrimental effects of chronic elevation of corticosterone, chicks might suppress adrenocortical activity in response to prolonged food shortages. In this study we examined temporal dynamics of corticosterone release in red-legged kittiwake (Rissa brevirostris) chicks exposed to prolonged restrictions in energy content and/or nutritional quality (low versus high lipid content) of their food. Starting at the age of 15 days, chicks were fed either high- or low-lipid fish at 40%, 65%, and 100% of ad libitum energy intake. Body mass measurements and baseline plasma samples were taken on a weekly basis after beginning of the treatment. After 3 weeks of treatment, chicks were exposed to a standardized acute handling and restraint stress protocol, where in addition to a baseline sample, three plasma samples were taken at intervals up to 50 min. We found that food-restricted chicks had lower body mass, chronically (during 2-3 weeks) elevated baseline and higher acute stress-induced levels of corticosterone compared to chicks fed ad libitum. Low lipid content of food further exacerbated these effects. An increase in baseline levels of corticosterone was observed within a week after energy requirements of food-restricted chicks exceeded their daily energy intake. A tendency for suppression of adrenocortical activity was observed in treatments fed low-lipid diets only at the end of the experiment. We suggest that nest-bound chicks, if food-stressed, might suffer deleterious effects of chronic elevation of corticosterone.
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Affiliation(s)
- A S Kitaysky
- Department of Zoology, University of Washington, Seattle 98195, USA.
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Pravosudov VV, Kitaysky AS, Wingfield JC, Clayton NS. Long-term unpredictable foraging conditions and physiological stress response in mountain chickadees (Poecile gambeli). Gen Comp Endocrinol 2001; 123:324-31. [PMID: 11589632 DOI: 10.1006/gcen.2001.7684] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Birds respond to short-term deterioration in foraging conditions by increasing their plasma level of corticosterone but the physiological effects of long-term deterioration in food supplies are not well known. In resident passerine birds that winter in temperate climates, such as the mountain chickadee (Poecile gambeli), the food supply may be limited and unpredictable over long periods of time. Whether the long-term limited and unpredictable food supply has an effect on (a) baseline levels of corticosterone and (b) the adrenocortical stress response to a standardized acute stress of handling and restraint in mountain chickadees was assessed. For a period of 94 days, one group of chickadees was maintained on limited and unpredictable food (food-restricted) and the other group was maintained on an ad libitum food supply. The food-restricted birds had significantly higher baseline levels of corticosterone than those maintained on ad libitum food. All birds responded to the acute stressor by an increasing secretion of corticosterone but there were no differences between the treatment groups in their stress response. There was a significant effect of sex on the stress response, with females reaching higher levels of corticosterone and responding at a faster rate than males. These results suggest that permanent resident birds wintering in harsh environments may have elevated levels of corticosterone on a long-term basis. Whereas other factors, such as day length and ambient temperature, may contribute to energetic hardship during the winter, the results showed that limited and unpredictable food alone can trigger significant changes in baseline levels of plasma corticosterone. The potential costs and benefits of long-term increased corticosterone levels in resident food-caching birds are discussed.
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Affiliation(s)
- V V Pravosudov
- Section of Neurobiology, Physiology, and Behavior, University of California Davis, Davis, California 95616-8519, USA
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Abstract
I tested whether the ability of chicks to suspend growth and developmental processes in response to food shortages is greater among alcids with food resources that fluctuate over short time periods than it is among close relatives with food that is continuously available. I examined changes in chick resting metabolic rate (RMR) in response to short-term food deprivation in horned and tufted puffins (intermittent food provisioning) and crested and parakeet auklets (continuous food provisioning). RMR was based on measurements of chick oxygen consumption rates (Vo2) under thermoneutral conditions. RMR of postabsorptive chicks scaled allometrically with body mass, and regression slopes were statistically indistinguishable among species. Mass-independent RMR of the same individuals decreased significantly after 48 h of food deprivation. The decrease in the mass-independent RMR was greater in puffins (46.8% in horned and 47.4% in tufted puffins) than in auklets (29.4% in crested and 23.7% in parakeet auklets). To test whether the observed decrease in RMR was due to less energy being allocated to growth, I examined developmental responses of horned and tufted puffins to experimental variation in rates of food intake. I found retarded growth rates in body mass, skeletal elements, and feathers in chicks experiencing low rates of food intake. The retardation of growth processes extended the developmental period. My findings suggest that developmental plasticity in juvenile alcids might be related to temporal variability of prey in oceanic environments.
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Affiliation(s)
- A S Kitaysky
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, 92717, USA.
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