Content of harbour seal (Phoca vitulina) and grey seal (Halichoerus grypus) scats in prey classified by functional groups (samples collected in the baie de Somme, France, from 2002 to 2019) ...

• Main Authors: Planque, Yann, Vincent, Cécile, Caurant, Florence, Spitz, Jérôme
• Format: Dataset
• Language: unknown
• Published: SEANOE 2020
• Subjects: Foraging ecology; Trophic; Marine mammals; Pinnipeds; Diet; Scat content; Faeces; Hard remains; Diagnostic hard parts; Fish otolith; Cephalopod beak; Harbour seals; Grey seals; Eastern English Channel; baie de Somme; harbour seal; Phoca vitulina
• Online Access: https://dx.doi.org/10.17882/76780; https://www.seanoe.org/data/00656/76780/

Harbour (Phoca vitulina) and grey seal (Halichoerus grypus) scat samples were collected in the baie de Somme, France, from 2002 to 2019 to identify the diet of both species. Diet analysis followed a procedure usually used for pinnipeds (e.g. Ridoux et al. 2007, https://doi.org/10.1017/S002531540705463X; Spitz et al. 2015, https://doi.org/10.1051/alr/2015001). Scats were washed in order to analyse their content in diagnostic hard prey remains (e.g. fish otoliths, fish bones and cephalopod beaks), and therefore to identify prey species consumed by seals. Key measurements on fish otoliths or cephalopod beaks were used to estimate body mass and length of prey consumed by seals (use of allometric relationships), and ultimately reconstruct seals’ diet content in mass (g). The content of seal scats are presented here in six functional groups of prey (small benthic flatfish with relative length < 200 mm, large benthic flatfish with relative length ≥ 200 mm, benthic non-flatfish, demersal fish, pelagic fish and ...