Self-foraging vs facilitated foraging by Lesser Black-backed Gull (Larus fuscus) at the Frisian Front, the Netherlands

The Lesser Black-backed Gull (Larus fuscus Linnaeus, 1758) is a surface feeder with a broad prey spectrum that forages in the North Sea on subsurface pelagic fishes and crabs swimming within 0.6 m of the sea surface. In July 2006 and in July/August 2009 we surveyed the Frisian Front area in the southern North Sea (53.4oN-54.3oN 4.0oE-5.5oE) to determine the prey base for Lesser Black-backed Gulls. In July/August 2009 we conducted bird counts in an integrated ecosystem survey by simultaneously sampling subsurface pelagic prey by a combination of fishing and echosounding. Lesser Black-backed Gul... Mehr ...