Fish and squid in the diet of king penguin chicks, Aptendonytes patagonicus, during winter at sub-antarctic Crozet Islands

• Published in: Marine Biology
• Main Authors: Cherel, Y., Ridoux, V., Rodhouse, P.G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer 1996
• Subjects: Antarctic; Austral; Indian; Antarc*; Crozet Islands; King Penguins
• Online Access: https://oceanrep.geomar.de/id/eprint/50945/; https://oceanrep.geomar.de/id/eprint/50945/1/3065.pdf; https://doi.org/10.1007/BF00351323

The diet of king penguins, Aptendonytes patagonicus, rearing chicks was studied during three consecutive austral winters (1990, 1991 and 1992) at Crozet Islands. The mean stomach content mass of the 47 samples was 503g. Percentages of wet and reconstituted masses showed that both fishes (66 and 36% respectively) and squid (34 and 64%) are important components of the winter diet. Juveniles of the demersal onychoteuthid squid Moroteuthis ingens from the bulk of the cephalopod diet, and this was the main species of mycophids eaten in summer by king penguins were either very rare in winter (Electrona carlsbergi) or accounted for a smaller proportion of the diet (Krefftichthys anderssoni = 1.5% by mass and Protomyctophum tenisoni = 4.6%). Five other myctophids, which are rarely consumed in summer, contributed 24% of the diet by mass in winter (Gymnoscopelus piabilis = 18.1%, Lampichthys procerus = 2.4%, G. nicholsi = 1.3%, and Metelectrona ventralis and Electrona subaspera = 1.0%). The greater diversity of prey in winter suggests a more opportunistic feefing behaviour at a time probably marked by a change in prey availability. Both the known ecology of the fish and squid prey and the barely digested state of some items suggest that in winter breeding adults forage in the outer shelf, upper slope and oceanic areas in the close vicinity of the Crozet Islands to feed their chicks. Finally, using kind penguins as biological samplers, the present work provides novel data on the previously unstudied mesopelagic/epibenthic marine community in waters surrounding the Crozet Islands. Seventeen myctophid fish have been identified to species level. These include several poorly known species in the southern Indian Ocean. The occurence of small, nearly intact, cephalopods in the diet of king penguins suggests that spwaning grounds of four squid species may be located near the Crozet Islands. Seventeen myctophid fish have been identified to species level. These include several poorly known species in the southern Indian Ocean. The ...