Bird Bio: Eared Grebe
This summer KBO is implementing its third season of aquatic bird surveys as part of the OregonCoordinated Aquatic Bird Monitoring Program. As part of this coordinated monitoring effort, KBO is focusing on seven species of marsh-nesting, colonial aquatic birds, including the Eared Grebe—Podiceps nigricollis. The Eared Grebe is the most abundant grebe species in North America, with an estimated population of 3.7 million. In its breeding plumage the Eared Grebe is black with chestnut flanks, bright white underparts and a scarlet iris. Its most distinguishable feature is a fanshaped, reddish-orange tuft that extends from the eyes to the back of the head. Eared Grebes typically winter in saltwater estuaries along the Pacific Coast and breed in freshwater habitats. In Oregon the majority of breeding areas are in Klamath, Lake and Harney counties, while breeding occurs in California in the east-central and northeastern portion of the state. Eared Grebes nest in large colonies, sometimes numbering in the thousands, in shallow water one to four feet deep. KBO survey crews have found Eared Grebes at more than 40 sites in southcentral Oregon. The status of Eared Grebes is of interest in the Klamath-Siskiyou bioregion in part because the region’s many lakes are subject to year to-year water level fluctuations which can impact Eared Grebe’s nesting habitat. Understanding water level impacts on Eared Grebes on their breeding habitats will be key to maintaining their abundance. Note: The Oregon Coordinated Aquatic Bird Monitoring Program is part of a large, multi-partner effort to determine the status of aquatic birds through the Western United States and to better inform waterbird management and conservation decisions. Source: Marshall, David B., Matthew G. Hunter and Alan L. Contreras, eds. Birds of Oregon: A General Reference. Corvallis: Oregon State University Press, 2003. This article can be found in KBO’s Summer 2010 Newsletter.