Binary dietary responses of northern gannets Sula bassana indicate changing food web and oceanographic conditions
نویسندگان
چکیده
منابع مشابه
Contrasting foraging tactics by northern gannets (Sula bassana) breeding in diVerent oceanographic domains with diVerent prey Welds
In order to forage and to provision oVspring eVectively, seabirds negotiate a complex of behavioural, energetic, environmental and social constraints. In Wrst tests of GPS loggers with seabirds in North America, we investigated the foraging tactics of free-ranging northern gannets (Sula bassana) at a large and a mediumsized colony that diVered in oceanography, coastal position and prey Welds. G...
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When animals move across a landscape, they alternate between active searching phases in areas with high prey density and commuting phases towards and in-between profitable feeding patches. Such active searching movements are more sinuous than travelling movements, and supposedly more costly in energy. Here we provide an empirical validation of this long-lasting assumption. To this end, we evalu...
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ژورنال
عنوان ژورنال: Marine Ecology Progress Series
سال: 2007
ISSN: 0171-8630,1616-1599
DOI: 10.3354/meps07075