Trophic niches of a seabird assemblage in Bass Strait, south-eastern Australia

PeerJ

article

Aymeric Fromant¹  Nicole Schumann¹  Peter Dann³  Yves Cherel²  John P.Y. Arnould¹ 

[1] School of Life and Environmental Sciences, Deakin University;Centre d’Edutes Biologiques de Chizé ,(CEBC), UMR 7372 du CNRS—La Rochelle Université;Research Department

关键词: Seabirds;    Stable isotopes;    Isotopic niche;    Trophic niche;    Diet;    Niche segregation;    Southern Ocean;    Penguin;    Procellariiform;   

DOI  :  10.7717/peerj.8700

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

The foraging niches of seabirds are driven by a variety of factors, including competition for prey that promotes divergence in trophic niches. Bass Strait, south-eastern Australia, is a key region for seabirds, with little penguins Eudyptula minor, short-tailed shearwaters Ardenna tenuirostris, fairy prions Pachyptila turtur and common diving-petrels Pelecanoides urinatrix being particularly abundant in the region. The trophic niches of these species were investigated using isotopic values in whole blood and by identifying prey remains in stomach contents. The four species occupied different isotopic niches that varied among years, seasons and regions. Little penguins consumed mainly fish whereas the three procellariforms primarily consumed coastal krill Nyctiphanes australis. The dietary similarities between the procellariforms suggest that food resources are segregated in other ways, with interspecific differences in isotope niches possibly reflecting differential consumption of key prey, divergent foraging locations and depth, and differences in breeding phenology. Because oceanographic changes predicted to occur due to climate change may result in reduced coastal krill availability, adversely affecting these seabird predators, further information on foraging zones and feeding behaviour of small procellariform species is needed to elucidate more fully the segregation of foraging niches, the capacity of seabirds to adapt to climate change and the potential for interspecific competition in the region.

【 授权许可】

CC BY