The imperial shag (Phalacrocorax atriceps) in the Nahuel Huapi lake (northwestern Patagonia, Argentina): distribution, abundance, and potential threats from scavenging birds

we describe the distribution and breeding abundance of the imperial shag (phalacrocorax atriceps) in the northern portion of the nahuel huapi lake (northwestern patagonia, argentina) during the 2006-2007 and 2007-2008 reproductive seasons. we recorded low population numbers and null breeding success in both seasons. attacks from several scavenging birds were recorded, and breeding activities were interrupted abruptly. future studies should consider the potential threats from scavenging birds, subsidized by urban garbage dumps, over this freshwater shag.