Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population
International audience Accurately estimating predators’ diets at relevant spatial and temporal scales is key to understanding animals’ energetics and fitness, particularly in populations whose decline might be related to their diet such as northern fur seals Callorhinus ursinus. Our goals were to im...
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ftunivrochelle:oai:HAL:hal-01660663v1 2024-02-11T10:09:30+01:00 Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population Jeanniard-Du-Dot, Thiphaine Thomas, Austen C Cherel, Yves Trites, Aw Guinet, Christophe Institut Maurice -Lamontagne Ministère des Pêches et des Océans Smith-Root USA Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) 2017-12-07 https://hal.science/hal-01660663 https://doi.org/10.3354/meps12381 en eng HAL CCSD Inter Research info:eu-repo/semantics/altIdentifier/doi/10.3354/meps12381 hal-01660663 https://hal.science/hal-01660663 doi:10.3354/meps12381 ISSN: 0171-8630 EISSN: 1616-1599 Marine Ecology Progress Series https://hal.science/hal-01660663 Marine Ecology Progress Series, 2017, 584, pp.1 - 16. ⟨10.3354/meps12381⟩ [SDE]Environmental Sciences info:eu-repo/semantics/article Journal articles 2017 ftunivrochelle https://doi.org/10.3354/meps12381 2024-01-23T23:35:31Z International audience Accurately estimating predators’ diets at relevant spatial and temporal scales is key to understanding animals’ energetics and fitness, particularly in populations whose decline might be related to their diet such as northern fur seals Callorhinus ursinus. Our goals were to improve the accuracy of diet estimates and extend understanding of feeding ecology by combining 2 scat-based methods of diet determination (hard-part identification and DNA-metabarcoding) with stable isotope measurements and individual behavioural data. We collected 98 scats on a northern fur seal breeding colony. We also tracked 20 females with biologgers, and took blood samples to determine δ13C and δ15N values as proxies for seal foraging habitat and diet. Results show that diet composition from hard-parts analysis corresponded well with DNA results, with DNA yielding a greater diversity of prey species at a finer taxonomic level. Overall, scat-based methods showed that seals mostly fed on neritic shelf-associated prey. Cluster analyses of combined hard-parts and DNA results however identified 2 diet groups, one mostly neritic and the other mostly pelagic. Stable isotopes and behavioural data revealed that 40% of seals fed in oceanic waters on pelagic prey. This is more than indicated by scat-based analyses, which are likely biased towards animals foraging closest to the colony and underestimate some dietary specializations within the population. Consequently, the combination of multiple methods for diet identification with at-sea tracking of individuals can help identify and quantify specialist groups within a population and provide a wider spatial and temporal ecological context for dietary analysis. Article in Journal/Newspaper Callorhinus ursinus Northern fur seal HAL - Université de La Rochelle Marine Ecology Progress Series 584 1 16 |
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English |
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[SDE]Environmental Sciences |
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[SDE]Environmental Sciences Jeanniard-Du-Dot, Thiphaine Thomas, Austen C Cherel, Yves Trites, Aw Guinet, Christophe Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population |
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[SDE]Environmental Sciences |
description |
International audience Accurately estimating predators’ diets at relevant spatial and temporal scales is key to understanding animals’ energetics and fitness, particularly in populations whose decline might be related to their diet such as northern fur seals Callorhinus ursinus. Our goals were to improve the accuracy of diet estimates and extend understanding of feeding ecology by combining 2 scat-based methods of diet determination (hard-part identification and DNA-metabarcoding) with stable isotope measurements and individual behavioural data. We collected 98 scats on a northern fur seal breeding colony. We also tracked 20 females with biologgers, and took blood samples to determine δ13C and δ15N values as proxies for seal foraging habitat and diet. Results show that diet composition from hard-parts analysis corresponded well with DNA results, with DNA yielding a greater diversity of prey species at a finer taxonomic level. Overall, scat-based methods showed that seals mostly fed on neritic shelf-associated prey. Cluster analyses of combined hard-parts and DNA results however identified 2 diet groups, one mostly neritic and the other mostly pelagic. Stable isotopes and behavioural data revealed that 40% of seals fed in oceanic waters on pelagic prey. This is more than indicated by scat-based analyses, which are likely biased towards animals foraging closest to the colony and underestimate some dietary specializations within the population. Consequently, the combination of multiple methods for diet identification with at-sea tracking of individuals can help identify and quantify specialist groups within a population and provide a wider spatial and temporal ecological context for dietary analysis. |
author2 |
Institut Maurice -Lamontagne Ministère des Pêches et des Océans Smith-Root USA Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) |
format |
Article in Journal/Newspaper |
author |
Jeanniard-Du-Dot, Thiphaine Thomas, Austen C Cherel, Yves Trites, Aw Guinet, Christophe |
author_facet |
Jeanniard-Du-Dot, Thiphaine Thomas, Austen C Cherel, Yves Trites, Aw Guinet, Christophe |
author_sort |
Jeanniard-Du-Dot, Thiphaine |
title |
Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population |
title_short |
Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population |
title_full |
Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population |
title_fullStr |
Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population |
title_full_unstemmed |
Combining hard-part and DNA analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population |
title_sort |
combining hard-part and dna analyses of scats with biologging and stable isotopes can reveal different diet compositions and feeding strategies within a fur seal population |
publisher |
HAL CCSD |
publishDate |
2017 |
url |
https://hal.science/hal-01660663 https://doi.org/10.3354/meps12381 |
genre |
Callorhinus ursinus Northern fur seal |
genre_facet |
Callorhinus ursinus Northern fur seal |
op_source |
ISSN: 0171-8630 EISSN: 1616-1599 Marine Ecology Progress Series https://hal.science/hal-01660663 Marine Ecology Progress Series, 2017, 584, pp.1 - 16. ⟨10.3354/meps12381⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.3354/meps12381 hal-01660663 https://hal.science/hal-01660663 doi:10.3354/meps12381 |
op_doi |
https://doi.org/10.3354/meps12381 |
container_title |
Marine Ecology Progress Series |
container_volume |
584 |
container_start_page |
1 |
op_container_end_page |
16 |
_version_ |
1790609421439598592 |