Creatures of habit: consistency in foraging behavior of Imperial Shags Phalacrocorax atriceps

S HARRIS; A RAYA REY; C ZAVALAGA; F QUINTANA

IBIS

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2014 p. 523 - 533

0019-1019

Individual consistency in foraging behaviour can generate behavioural variability withinpopulations and may, ultimately, lead to species diversification. However, individualbasedlong-term behavioural studies are particularly scarce in seabird species. Between2008 and 2011, breeding Imperial Shags Phalacrocorax atriceps at the Punta Le
on colony,Argentina, were tracked with GPS devices to evaluate behavioural consistency duringtheir foraging trips. Within a breeding season, individuals were highly consistent in themaximum distances they reached from the shore and the colony, as well as in the timeinvested in flight and diving across consecutive days during early chick rearing. In addition,each individual had its specific foraging area distinct from the foraging area of otherindividuals. Comparing between early and late chick rearing in the same season, individualswere consistent, to a lesser degree, in the maximum distance they reached from thecolony and the shore, increasing in consistency later on in the season. Within the season,females were more consistent than males in the maximum distance they moved fromthe colony and the shore, the sexes segregated in their foraging areas and individualfemales were segregated from one another. Twenty-eight individuals tracked in differentbreeding seasons were marginally consistent in their trip durations and maximum distancereached from shore across seasons. Among seasons, foraging locations differedbetween sexes and among individual females. Individuals from this colony exhibited consistencyover time in several aspects of foraging behaviour, which may be due to a combinationof individual characteristics such as learning abilities, breeding experience orhealth, as well as targeted prey type and stability of the environment at this location.