Eastern rockhopper penguins Eudyptes filholi as biological samplers of juvenile and sub-adult cephalopods around Campbell Island, New Zealand

• Published in: Polar Biology
• Main Authors: Xavier, J. C., Cherel, Yves, Ceia, R., Queirós, P., Guimarães, B., Rosa, R., Cunningham, D., Moors, P., Thompson, D.
• Other Authors: MARE – Marine and Environmental Sciences Centre Portugal, Universidade de Coimbra Coimbra, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), 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), MARE – Marine and Environmental Sciences Centre, Faculdade de Ciencias da Universidade de Lisboa, Department of Conservation New Zealand, Department of Conservation, National Institute of Water and Atmospheric Research Auckland (NIWA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: Eastern rockhopper penguins; Diet; Martialia hyadesi; Onykia ingens; Octopus campbelli; Pelagic squid; [SDE]Environmental Sciences; Campbell Island; New Zealand; Southern Ocean; Polar Biology
• Online Access: https://hal.archives-ouvertes.fr/hal-01879622; https://doi.org/10.1007/s00300-018-2333-2

International audience Early life-history stages of cephalopods are known to play an important role as prey in food webs of the Southern Ocean, butlittle information is available about their biology and availability to predators. Top predators, such as penguins, are knownto feed regularly on coastal juvenile/sub-adult cephalopods. Using eastern rockhopper penguins Eudyptes filholi as coastalbiological samplers, we examined in detail the cephalopod component of their diet in Campbell Island (New Zealand) duringtwo consecutive breeding seasons in order to evaluate (1) the relative importance of cephalopods (by frequency of occurrence,by number and by mass) to the diet of both adult and chick penguins, (2) the habitat and trophic levels of the cephalopodsin the region and (3) the status of the juvenile/sub-adult cephalopod community in the waters around Campbell Island. Ourresults show that eastern rockhopper penguins feed on eight species of juvenile and sub-adult cephalopods, with Onykiaingens, Martialia hyadesi and Octopus campbelli being the most important species by frequency of occurrence, number andmass. Differences between the diets of adult and chick penguins and between breeding seasons were found. Habitat (δ13C)and trophic level (δ15N) information also showed that all cephalopod species (and all studied stages) occupy similar habitaton the Campbell shelf, with M. hyadesi showing lower δ15N values than O. ingens and O. campbelli. This study indicatesthat eastern rockhopper penguins can be valuable biological samplers of local juvenile/sub-adult cephalopods (includingpoorly known cephalopod species) around Campbell Island when breeding, that these cephalopods were likely to be caughtnaturally (not from fisheries), providing relevant information for the conservation of these penguins.