Conventional and molecular analysis of the diet of gentoo penguins: contributions to assess scats for non-invasive penguin diet monitoring

• Published in: Polar Biology
• Main Authors: Xavier, José, Cherel, Yves, Medeiros, Renata, Velez, Nadja, Dewar, Meagan, Ratcliffe, Norman, Carreiro, Ana, Trathan, Phil
• Other Authors: British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Institute of Marine Research - Department of Life Sciences Portugal, University of Coimbra Portugal (UC), Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), School of Biosciences Cardiff, Cardiff University, chool of Applied and Biomedical Sciences, Federation University Australia
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: Conservation; Pygoscelis papua; Southern Ocean; Prey genetics; Feeding ecology; [SDE]Environmental Sciences; Antarctic; Antarc*; Euphausia superba; Polar Biology
• Online Access: https://hal.archives-ouvertes.fr/hal-01881988; https://doi.org/10.1007/s00300-018-2364-8

International audience There is a growing search for less invasive methods while studying the diet of Antarctic animals in the wild. Therefore,we compared the diet of gentoo penguins from stomach contents (i.e. through visual identification of prey remains) andscats (i.e. faeces), and further compared prey DNA assay in fresh and old scats. Prey remains identified visually in stomachcontents and scats were broadly comparable: the crustaceans and fish were the most important components, with Themistogaudichaudii clearly being the most frequent and numerous prey species in both sampling methods. By mass, differencesin species frequency were observed in stomach contents (Parachaenichthys georgianus) and scats (Champsocephalus gunnari),with the former fish species absent in scats. Differences were detected in the most frequent prey (T. gaudichaudiiand Euphausia superba) and in various fish species, most with bigger sizes in scats. Allometric equations to estimate mostcrustacean’s sizes (i.e. relationships between carapace and mass/total length) are needed. For DNA studies, when comparingDNA from fresh and old scats, both provided similar results that, in general, were also similar to the visual analysis. In orderto use penguin scats (along with the use of DNA analyses) for monitoring purposes, allometric equations to estimate massand size of prey (most crustaceans) and better designed species-specific primers are needed for targeting key prey species(e.g. Euphausia superba, T. gaudichaudii). These DNA methodologies can complement other methods (i.e. visual analysesand stomach contents analyses) in monitoring programs of penguins.