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Potential Genetic Distinctiveness of the Disjunct Western Yellow Rail Population
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Breeding Yellow Rails are widely distributed in marshes across the boreal and plains zones of Canada and the northernmost U.S. states, with the exception of approximately 600 Yellow Rails that breed in Klamath and western Lake counties in south-central Oregon. Half of these use the Klamath Marsh National Wildlife Refuge, the rest occur in marshes on private and Federal lands within a 45 mile radius of Klamath Marsh NWR. Field work (by Ken Popper, Mark Stern, and Susan Lundsten) has yielded good information on habitat requirements of Yellow Rails which will help in their management, but little is known about where they winter, their needs during migration, and their relatedness to other breeding populations.
Historical records suggest that Yellow Rails have long occupied marshes in the western U.S. There are breeding records from Mono Co., CA from the 1920’s to 1950, and breeding in OR was confirmed at Aspen Lake, Klamath Co. in 1926. Inventories beginning in 1982 confirmed a more extensive distribution in the Klamath region. Historical and a few recent records suggest that these rails winter in California’s bay-delta, the Central Valley, and possibly in Humboldt Bay marshes. All this suggests that a disjunct breeding population has existed for some time along the eastern margin of the Cascade-Sierra crest, and that they migrate to coastal regions in the winter. Traditional taxonomic treatment has distinguished only two subspecies in North America, Coturnicops noveboracensis noveboracensis in the U.S., and C. n. goldmani in Mexico (not seen since 1964), but western birds have not received careful scrutiny to date. Banding studies over the last 10 years throughout their range show no evidence of interaction between the eastern and western populations. Genetic analyses are the next step to help us confirm the supposition that this very small and geographically isolated population is also genetically unique.
This project comprises two stages; this first
Haig, Susan M. - Supervisory Research Wildlife Biologist
Phone: 541-750-7482
Email: susan_haig@usgs.gov
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