Winter habitat of common loons on the continental shelf of the Southeastern United States

Abstract

Population size, habitat use, and habitat selection of wintering Common Loons (Gavia immer) were studied on the southeastern U.S. continental shelf. Winter pop- ulation estimates ranged from 8700 to 20,000 individuals for the shelf between 29? and 35?N latitude. Loons used shelf waters up to 100 m in depth and 100 km from land. Significant differences in habitat use and selection were found among four shelf habitats differentiated by water depth, distance from land, and water mass properties. Loons selected for waters 0-19 m deep but avoided highly turbid waters within 5-15 km of shore. Loon distribution shifted farther offshore during midwinter, as the areal extent of turbid water