The U.S. Fish and Wildlife Service this week it has completed a five-year status review of the endangered Columbia Basin pygmy rabbit that says it remains endangered and some threats have increased.
The reviewers found increased risk from disease in captivity, habituation to captive conditions likely making some individuals less capable of surviving in the wild, and loss of genetic uniqueness due to interbreeding with pygmy rabbits from other populations.
The complete status review may be found at: http://www.fws.gov/wafwo/species.html
The USFWS also announced that it is beginning the process to amend the draft Columbia Basin pygmy rabbit recovery plan originally distributed for public review and comment in August 2007. On completion of the process the agency will seek public review and comment on the amended draft recovery plan.
The USFWS listed the Columbia Basin distinct population segment of the pygmy rabbit under emergency provisions of the Endangered Species Act in 2001 and fully listed it on March 5, 2003.
The pygmy rabbit is the smallest rabbit in North America. Adults weigh about 1 pound and measure less than a foot in length. In the wild, pygmy rabbits are typically found in sagebrush habitat, and primarily eat sagebrush, native bunchgrasses, and other perennial plants. The pygmy rabbit is one of only two rabbit species in North America that digs its own burrows and therefore is most often found in areas that include both suitable foods and relatively deep, loose soils that allow burrowing.
Historically, the Columbia Basin pygmy rabbit was likely found in appropriate shrub-steppe habitat in portions of Douglas, Grant, Lincoln, Adams, Franklin, and Benton counties in Washington.
The last known population of the Columbia Basin pygmy rabbit in the wild was believed to be extinct by mid-2004, although other wild populations may still occur in unsurveyed areas of central Washington. In 2007, twenty captive-bred pygmy rabbits were reintroduced to central Washington habitats historically occupied by the species. These captive-bred animals experienced a high level of predation and it is unlikely any survived through the fall of 2007. Biologists will be able to apply knowledge gained from that release to help improve survival rates of future releases.
The USFWS considers the Columbia Basin pygmy rabbit a DPS because the population is separate from others of its kind and its conservation is significant to the remainder of the species. The Columbia Basin pygmy rabbit has been isolated from other pygmy rabbit populations for at least 10,000 years, as suggested by the fossil record and genetic analyses. This DPS is the only population of the species that occurs in the unusual ecological setting of the Columbia Basin and it is markedly different genetically from other pygmy rabbit populations.
"Recovery of the Columbia Basin pygmy rabbit will require creative efforts," said Ken Berg, manager of the Service's Washington Fish and Wildlife Office in Lacey, Wash. "Close collaboration with our partners and stakeholders will be essential to an effective recovery program for this population."
The USFWS, in partnership with the Washington Department of Fish and Wildlife, has a program to enroll non-federal land owners who are interested in helping conserve the Columbia Basin pygmy rabbit. Participation in the voluntary Safe Harbor Agreement provides landowners and managers with assurances that future land-use restrictions will not be imposed on them if they voluntarily implement management measures that would be expected to benefit the Columbia Basin pygmy rabbit.