Diving patterns of breeding female rockhopper penguins (Eudyptes chrysocome): Noir Island, Chile

RAYA REY, A.; PÜTZ, K; LUNA-JORQUERA, G.; LÜTHI, B.; SCHIAVINI, A

POLAR BIOLOGY

SPRINGER

Año: 2009 vol. 32 p. 561 - 568

0722-4060

The diving behaviour of female southern rockhopperpenguins (Eudyptes chrysocome) was studied atNoir Island (54°30
S–73°00
W), Chile, in the southeastPaciWc Ocean. This isolated island is located at the edge ofthe continental shelf in an area where the Humboldt Currentoriginates, and holds a population of more than 150,000breeding pairs. On 13 December 2005, four TDRs weresuccessfully attached to females at the end of the broodingperiod and recorded diving activity at intervals of 2 s overthe next 4 weeks. In total, 40 complete foraging trips wererecorded. Trip duration was on average 42.4 § 40.1 h andthe proportion of overnight trips (60%) was the highestvalue found so far for this species. Mean dive depth anddive duration was 20.6 § 19.4 m and 63.7 § 36.4 s, respectively.The diving eVort was higher than that of broodingfemales from the Indian Ocean and comparable with that ofconspeciWcs from colonies in the southwest Atlantic interms of diving rate (38 § 14.2 dives h¡1), but slightlylower as regards the proportion of time spent underwater(61 § 10.5%). This study conWrms that the diving behaviourof rockhopper penguins varies as a function of thephysical and biological characteristics of the foraging areasand of the particular stage of the breeding season.