CADIC   02618
CENTRO AUSTRAL DE INVESTIGACIONES CIENTIFICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Individuals within the average: multiple foraging trips of breeding male Rockhopper penguins (Eudyptes chrysocome).
Autor/es:
S HARRIS; K PÜTZ; A RAYA REY
Reunión:
Congreso; 2nd World Seabird Conference; 2015
Resumen:
Total variability detected in seabird behavior over a given time period may be explained, to someextent, by differences amongst individuals and these differences provide evidence of the behavioralflexibility they present and, ultimately, their vulnerability to changes that may occur in theenvironment. Forty-four male Southern Rockhopper Penguins (Eudyptes chrysocome) breeding at"Rookery Valley" (51° 36´ S 57 °55´ W) were equipped with either GPS-TDlog or TDR loggers forseveral foraging trips during incubation (a total of 144 trips by 18 individuals in 2012 and a total of230 trips by 27 individuals in 2013). Individuals did not forage far from the colony as GPS positionswere within 6km from the breeding grounds. Foraging durations was longer, on average, in 2013than in 2012, increased throughout the study period and differences were detected amongst individual birds (35% of variability). The time individuals began diving respective to sunrise was laterin 2012 than in 2013 (10.4 ± 3.1h vs. 9.8 ± 3.3h after sunrise), increased throughout this time periodand differences amongst individuals were also significant (accounting for 37% of variability). Inaddition, timing of the last dive respective to sunset decreased throughout this period, as individualsfinished diving later in the day, and differences amongst individuals were also significant (43% ofvariability). Maximum depths reached differed between years, and differences were also detectedamongst individuals (22% of variability). Individual-based longitudinal studies provide us withevidence that in spite of there not being large differences in habitat use within a sampled group(foraging in similar locations), differences amongst individuals can account for a large portion of theobserved variability in foraging parameters. Therefore, individuals would be behaving moreconsistently than would appear if one based interpretations on transversal studies.