King penguins in the Magellan Strait, Chile: Inshore foraging throughout the year indicates substantial behavioural plasticity

CAMPOS FUENTES, CAMILA; LUTHI, BENNO; PUTZ, KLEMENS; SIMEONE, ALEJANDRO; PEDRANA, JULIETA; GARCIA BORBOROGLU, P.

Cape Town

Conferencia; 9th International Penguin Congress; 2016

King penguins (Aptenodytes patagonicus) are considered as oceanic mesopredators, foraging predominantly in frontal systems. However, since 2010 increasing numbers of king penguins frequent the Magellan Strait, Chile, and a prospective breeding ground has been established at Bahía Inútil (53 27?42.11S, 69 18?32.42W) , a bay to the east of the Magellan Strait. This location is more than 300 km away from the open sea in the Atlantic and Pacific Oceans, respectively, and thus provides an inshore habitat that differs largely from the usual high-sea foraging sites of king penguins. The aim of this study was to gain first insights into the foraging behaviour of this species settling in the Magellan Strait and to elucidate potential adaptations to this inshore environment.In December 2014, 5 GPS- and 7 Time-Depth-Recorders were attached to individuals engaged in courtship or just after egg-laying. Furthermore, 10 satellite transmitters were attached to birds of unknown breeding status in March 2015 to monitor their movements for the winter months. By chance, one parent of the first and only successfully fledged chick was selected. During the incubation period and during winter, all but one birds remained in the vicinity of the breeding site. Courtshipping birds foraged in the Bahía Inútil ventured not further than 30 km away from the colony for periods of up to 5 days , while incubating birds foraged up to 125 km away in the Magellan Strait for periods of up to 12 days. These differences were mirrored in the diving behaviour of the birds, with those foraging in the strait diving deeper and longer. During the winter period, the foraging range was expanded and fjords and channels adjacent to the strait were also used. However, one bird left the Magellan Strait eastwards, then turned south into the Drake Passage before heading ca. 2000 km west into the Pacific, where it remained for 71 days. Afterwards, the bird headed eastwards again, passed Cape Horn and continued travelling east until it reached South Georgia.The results on the foraging behaviour of king penguins are compared to the behaviour of conspecifics from traditional, highly oceanic breeding and foraging areas, and discussed with regard to behavioural plasticity required to forage successfully in the Magellan Strait. Finally, the results may provide some insights into the adaptations necessary to cope with global warming, which is predicted to negatively impact king penguins at least at the Crozet Islands.