Foraging Behavior and the Dispersion of Pelagic Birds

点击翻译按钮获取中文摘要

The relationship between krill and its consumers is considered crucial to the dynamics of the Antarctic ecosystem. To date, most studies of this relationship have concentrated on simply describing patterns of association. This research will go beyond a descriptive approach, and probe the mechanisms that generate patterns of association between selected seabirds and patches of krill. The focus is on seabird species that are abundant at South Georgia in winter and that are known to feed heavily on krill: Gentoo Penguins, Common Diving-Petrels, Kerguelen Petrels and Blue Petrels. The study includes several components. These include the quantification of seabird distribution relative to the location and size of krill patches and the quantification of individual behavior of seabirds as a function of krill density, krill patch size, distance from krill patches and abundance of other consumers. Data on individual behavior will be used to construct partial differential equation models of seabird distribution. Patterns of association predicted by these models will be compared to observed patterns of association. Finally, an assessment of how birds actually capture prey such as krill, and how the potential cost of foraging increases as weather conditions become severe, will be made. This research will unite several lines of investigation into a synthesized portrait of how birds respond to spatial and temporal variability in resources within the Antarctic environment.