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Status: Population size: 84,000 Photo by Scott Somershoe.

Swainson's Warbler
(Limnothlypis swainsonii)

A drab but distinctive bird, the Swainson's Warbler is unusual for its two populations breeding in entirely different habitat types. Birds of the southeastern lowlands prefer wooded swamplands and canebrakes; those of the central and southern Appalachian Mountains are found in rhododendron thickets and other heavily wooded habitats. Because of its secretive nature, this species is more easily heard than seen.

Identification
Both sexes are brownish-olive above, dull white below. Both also show a brownish crown; long, whitish eyestripe (supercilium), and a long, pointed bill.

Distribution and Population Trends
Swainson's Warblers range from uncommon to locally common in their breeding range, which includes much of the southeast U.S. (excluding the Florida peninsula) north to Kentucky and Virginia, west to eastern Texas and Oklahoma. The species has experienced drastic declines in some areas, such as Illinois (where it has been almost extirpated), southern Missouri, and northeastern Oklahoma. Winters in eastern Mexico to northern Honduras. Also found in winter in the Bahamas, Cuba, Jamaica, and the Cayman and Swan islands.

Ecology
The bird's nest may be up to three meters in a bush or tangle. It is typically a robust cup consisting of dry leaves, moss, and pine needles and lined with grasses, moss, and rootlets. This species nests May through July. Females may fake injury to distract predators. Feeds primarily on insects.

Threats
Regional declines of this species are due primarily to habitat loss due to conversion of bottomland hardwood forests to croplands, reservoirs, and urban centers. Nest parasitism by Brown-headed and Shiny cowbirds due to forest fragmentation has also contributed to declines and is increasing. Loss and degradation of tropical forest habitat on wintering grounds have also been factors in declines.

Conservation
Habitat management for the Swainson's Warbler has been attempted at a number of national forests, national wildlife refuges, state lands, and private refuges but success has been limited. This may be because of a lack of a complete understanding of the habitat requirements of the species. To alleviate this problem a number of research projects are underway with funding provided by federal and state agencies.

What Can You Do?
Audubon's Important Bird Area program is a vital tool for the conservation of Swainson's Warblers as well as other species. To learn more about the Important Bird Areas program and how you can help, visit: http://www.audubon.org/bird/iba/.

Information on where Swainson's Warblers occur and in what numbers is vital to conserving the species. Help in monitoring this and other species by reporting your sightings to eBird. A project of Audubon and the Cornell Lab of Ornithology, eBird is the world's first comprehensive on-line bird monitoring program: http://www.audubon.org/bird/ebird/index.html.

U.S. National Wildlife Refuges provide essential habitat for Swainson's Warblers, and a great number of other species throughout the U.S. and its territories. Unfortunately, the refuge system is often under-funded during the U.S. government's budgeting process. To learn more about how you can help gain much needed funding for U.S. National Wildlife Refuges, visit: http://www.audubon.org/campaign/refuge_report/

Buy shade-grown coffee. Shade-grown coffee plantations provide wintering habitat for many Neotropical migrants, including the Swainson's Warbler. For more information about shade-grown coffee, visit Audubon's web site at http://www.audubon.org/local/cn/97december/sgsoca.html.

The Cornell Laboratory of Ornithology and the USDA Forest Service coordinate Birds in Forested Landscapes, a citizen-science project that links volunteer birders and professional ornithologists in a study of the habitat requirements of North American forest birds, including Swainson's Warbler. To learn more about Birds in Forested Landscapes, and how you can participate in the project, visit: http://birds.cornell.edu/bfl/

References
Dunn, J., and K. Garrett. 1997. Peterson Field Guides Warblers. Houghton Mifflin Company, Boston, New York.

Curson, J., D. Quinn, and D. Beadle. 1994. Warblers of the Americas. Houghton Mifflin Company, Boston, New York.