Bird Bio: Hermit Warbler
During the breeding season, the Hermit Warbler (Dendroica occidentalis) can be found in coniferous forests along the west coast of Oregon, Washington, and California, in the Cascade mountains of western Oregon and Washington, and in California’s Sierra Nevada mountains. This species winters in montane pine, pine-oak, and cloud forests of Mexico and Central America through Nicaragua. A small, insectivorous warbler, it has a yellow head, white underparts, and gray upperparts. Males have black throats, while females’ throats are grayish, with some black. The species is known to hybridize with Townsend’s Warblers, resulting in birds with plumage characteristics of both species. The Hermit Warbler is a habitat specialist. During breeding it is most often found in the interior of cool, moist, mature coniferous forests, from sea level into the mountains. It is most abundant in stands over 30 years old, and is not generally found in stands under 20 years old, or in stands that have been extensively thinned. As the Hermit Warbler usually resides high in the canopy, it is more often heard than seen. The male’s variable song is multi-part, consisting of 3 or 4 buzzy notes—“zeegle zeegle zeegle”—; followed by a rising-and-falling ending phrase—“zee-o-seet.” The Hermit Warbler is a State of the Birds western forest obligate species, meaning that it is dependent on coniferous forest habitats. It is also a Partners in Flight Watchlist Species. Partners in Flight’s Conservation Strategy for Landbirds in Coniferous Forests of Oregon and Washington identifies the Hermit Warbler as a focal species for mature, multi-layered, closed canopy forests. Through improving habitat conditions for Hermit Warbler, it is thought that other species that depend on older coniferous forest habitats will also benefit. There is concern that the Hermit Warbler may be declining due to extensive loss of mature forest habitats. The 2011 State of the Birds report indicates that National Forests support 51% of Hermit Warblers breeding in the United States. This high level of stewardship responsibility provides the U.S. Forest Service with a unique opportunity to reverse potential declines in Hermit Warblers through appropriate forest management that will, in turn, improve habitat conditions for a variety of western forest obligate species. Protecting and restoring the Hermit Warblers’ habitat throughout its breeding range will require collaborations among non-governmental organizations like KBO, the Forest Service, and other public and private forest mangers in Oregon, Washington, and California. Broader collaborations among international partners will also be necessary to ensure connectivity between Hermit Warblers’ breeding, migratory, and wintering habitats. This article appears in KBO’s Fall 2011 Newsletter.