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4. Multiple methods of diet assessment reveal differences in Atlantic puffin diet between ages, breeding stages, and years.

Author

Kennerley, William L., Clucas, Gemma V., and Lyons, Donald E.

Subjects
MARINE heatwaves, DIET, FORAGE fishes, FISH communities, BIOLOGICAL fitness
Abstract

Introduction: Atlantic puffin (Fratercula arctica, hereafter "puffin") reproductive success in the Gulf of Maine (GoM) has declined following a recent oceanographic regime shift that has led to rapid warming and increasingly frequent marine heatwaves. Concurrent changes in both the regional forage fish community and puffin chick diets and provisioning rates suggest that inadequate prey resources may be driving this decline. Traditional, noninvasive methods of diet assessment, however, are unable to determine seabird diet at many age classes and breeding stages. Methods: To determine what prey GoM puffins were feeding on during two years of marine heatwave conditions, we assessed puffin diet using two complementary methods: traditional, observational methods that utilize billload photography and emerging methods employing fecal DNA metabarcoding. We then examined the effect of methodology, age, breeding stage, and year on puffin diet composition. Results: We identified a strong correlation between the composition of chick diet as estimated through traditional and emerging methods, supporting the interpretation of DNA relative read abundance as a quantitative metric of diet composition. Both methods identified the same dominant prey groups yet metabarcoding identified a greater number of species and offered higher taxonomic resolution. Additionally, metabarcoding revealed adult puffin diet during the incubation period for the first time. Although puffin adults and chicks fed on many of the same prey types, adults consumed a greater variety of taxa and consumed more low quality prey types than they provisioned chicks. Discussion: For both age classes, diet varied both between and within years, likely reflecting changes in the local forage fish community in response to environmental variability. Puffins exploited unusual abundances of typically-uncommon prey during these two years of marine heatwave conditions, yet low puffin productivity suggests the observed dietary plasticity was not fully able to compensate for apparent prey shortages. Continued refinement of molecular methods and the interpretation of the data they provide will enable better assessments of how seabirds of diverse ages and breeding stages are adapting to changing prey communities. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Receding ice drove parallel expansions in Southern Ocean penguins

Author

Cole, Theresa L., Dutoit, Ludovic, Dussex, Nicolas, Hart, Tom, Alexander, Alana, Younger, Jane L., Clucas, Gemma V., Frugone, María José, Cherel, Yves, Cuthbert, Richard, Ellenberg, Ursula, Fiddaman, Steven R., Hiscock, Johanna, Houston, David, Jouventin, Pierre, Mattern, Thomas, Miller, Gary, Miskelly, Colin, Nolan, Paul, Polito, Michael J., Quillfeldt, Petra, Ryan, Peter G., Smith, Adrian, Tennyson, Alan J. D., Thompsona, David, Wieneckeb, Barbara, Viannac, Juliana A., and Waters, Jonathan M.

Published
2019

13. Evidence of Pathogen-Induced Immunogenetic Selection across the Large Geographic Range of a Wild Seabird

Author

Levy, Hila, primary, Fiddaman, Steven R, primary, Vianna, Juliana A, primary, Noll, Daly, primary, Clucas, Gemma V, primary, Sidhu, Jasmine K H, primary, Polito, Michael J, primary, Bost, Charles A, primary, Phillips, Richard A, primary, Crofts, Sarah, primary, Miller, Gary D, primary, Pistorius, Pierre, primary, Bonnadonna, Francesco, primary, Le Bohec, Céline, primary, Barbosa, Andrés, primary, Trathan, Phil, primary, Raya Rey, Andrea, primary, Frantz, Laurent A F, primary, Hart, Tom, primary, and Smith, Adrian L, primary

Published
2020
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16. Comparative population genomics reveals key barriers to dispersal in Southern Ocean penguins

Author

Clucas, Gemma V., primary, Younger, Jane L., additional, Kao, Damian, additional, Emmerson, Louise, additional, Southwell, Colin, additional, Wienecke, Barbara, additional, Rogers, Alex D., additional, Bost, Charles‐André, additional, Miller, Gary D., additional, Polito, Michael J., additional, Lelliott, Patrick, additional, Handley, Jonathan, additional, Crofts, Sarah, additional, Phillips, Richard A., additional, Dunn, Michael J., additional, Miller, Karen J., additional, and Hart, Tom, additional

Published
2018
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23. A SIMPLIFIED METHOD OF DETERMINING THE SEX OF PYGOSCELIS PENGUINS USING BILL MEASUREMENTS.

Author

POLITO, MICHAEL J., CLUCAS, GEMMA V., HART, TOM, and TRIVELPIECE, WAYNE Z.

Subjects
*SEXUAL dimorphism in animals, *DIMORPHISM in animals, *ADELIE penguin, *DNA, *CHINSTRAP penguin
Abstract

The article explores sexual dimorphism in bill size in adult Adelie Penguins Pygoscelis adeliae, adult Chinstrap Penguins P. antarctica and adult and juvenile Gentoo Penguins P. papua at King Goerge Island, Antarctica. A DNA-based molecular sexing technique has been used in this study. Results reveal that bill length and depth were the most consistent dimorphic character explored. Male Chinstrap and Gentoo Penguins had reportedly consistently longer and deeper bills versus their mates. Bill measurements were utilized to calculate species- and age-specific discriminant functions.

Published
2012

24. Dispersal in the sub-Antarctic: king penguins show remarkably little population genetic differentiation across their range

Author

Clucas, Gemma V., Younger, Jane L., Kao, Damian, Rogers, Alex D., Handley, Jonathan, Miller, Gary D., Jouventin, Pierre, Nolan, Paul, Gharbi, Karim, Miller, Karen J., and Hart, Tom

Subjects
Genotyping Techniques, Antarctic Regions, Aptenodytes patagonicus, Animals, Cluster Analysis, Southern Ocean, Genetic homogeneity, Ecosystem, Ecology, Evolution, Behavior and Systematics, Population Density, Principal Component Analysis, Geography, Discriminant Analysis, Genetic Variation, Colonisation, Bayes Theorem, Dispersal, Spheniscidae, RAD-Seq, Gene flow, Seabirds, Phylogeography, Genetics, Population, Animal Migration, Molecular ecology, Research Article
Abstract

Background Seabirds are important components of marine ecosystems, both as predators and as indicators of ecological change, being conspicuous and sensitive to changes in prey abundance. To determine whether fluctuations in population sizes are localised or indicative of large-scale ecosystem change, we must first understand population structure and dispersal. King penguins are long-lived seabirds that occupy a niche across the sub-Antarctic zone close to the Polar Front. Colonies have very different histories of exploitation, population recovery, and expansion. Results We investigated the genetic population structure and patterns of colonisation of king penguins across their current range using a dataset of 5154 unlinked, high-coverage single nucleotide polymorphisms generated via restriction site associated DNA sequencing (RADSeq). Despite breeding at a small number of discrete, geographically separate sites, we find only very slight genetic differentiation among colonies separated by thousands of kilometers of open-ocean, suggesting migration among islands and archipelagos may be common. Our results show that the South Georgia population is slightly differentiated from all other colonies and suggest that the recently founded Falkland Island colony is likely to have been established by migrants from the distant Crozet Islands rather than nearby colonies on South Georgia, possibly as a result of density-dependent processes. Conclusions The observed subtle differentiation among king penguin colonies must be considered in future conservation planning and monitoring of the species, and demographic models that attempt to forecast extinction risk in response to large-scale climate change must take into account migration. It is possible that migration could buffer king penguins against some of the impacts of climate change where colonies appear panmictic, although it is unlikely to protect them completely given the widespread physical changes projected for their Southern Ocean foraging grounds. Overall, large-scale population genetic studies of marine predators across the Southern Ocean are revealing more interconnection and migration than previously supposed. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0784-z) contains supplementary material, which is available to authorized users.

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