The Columbia Basin pygmy rabbit is listed as a federal endangered and state endangered species (WAC 220-610-010). In Washington, ‘’endangered" means any wildlife species native to the state that is seriously threatened with extinction throughout all or a significant portion of its range within the state.
The population of Columbia Basin pygmy rabbit is low and is designated as a Distinct Population Segment for protection under the U.S. Endangered Species Act. Conservation threats to the Columbian Basin pygmy rabbit include loss and degradation of shrubsteppe primarily due to conversion and fragmentation of this habitat to cropland for agriculture and development.
Description and Range
The pygmy rabbit is the smallest rabbit species in North America. It can grow up to 11 inches long and weigh up to 16 ounces. It has a slate gray coloration that can turn brown during the summer months. Its ears are short and its tail is nearly invisible. Adult females are slightly larger than adult males.
Ecology and life history
Pygmy rabbits are sagebrush obligates, depending on this habitat for survival. Dense stands of sagebrush provide pygmy rabbits with year-round food and shelter. Native, perennial grasses and forbs provide an important food source beginning in spring and especially in summer and fall and deep, friable soils allow them to construct burrows.
The pygmy rabbit is one of only two North American rabbits known to dig its own burrows. Burrows are used for shelter, thermoregulation (to regulate body temperature), and safety from predators. Burrow systems are generally found on mounds or gentle slopes.
Big sagebrush is the primary food source, comprising 90 percent of the winter diet, but grasses and forbs are also eaten in spring and summer. Activity occurs throughout the year, and pygmy rabbits may be active any time of day or night (although most activity occurs during the twilight hours).
Breeding extends from Feb. to July. Specialized natal burrows, where females give birth to young, are excavated separate from residential burrows. Females have two to four litters per year with up to six kits per litter.
Predators include weasels, coyotes, American badgers, hawks, owls, and other carnivorous mammals and birds.
Pygmy rabbits inhabit sagebrush-dominated areas of the Great Basin in portions of Oregon, California, Nevada, Utah, Idaho, Montana, and Wyoming. The Washington population has been isolated from the remainder of the species' range for at least 10,000 years, and possibly as long as 40,000 to 115,000 years.
The Columbia Basin pygmy rabbit population is geographically and genetically discrete from the remainder of the taxon and this population is significant due to the unique ecological setting (i.e., geologic, climate, soil, and vegetation community) in which it occurs.
Museum specimen records and reliable sight records show that pygmy rabbits once occupied sagebrush habitat in Benton, Adams, Grant, Lincoln, and Douglas counties. Paleontological evidence suggest the species prehistorically had a broader distribution that also included Franklin, Kittitas, Chelan, Yakima, and Whitman counties.
By 2001, only one population remained at Sagebrush Flat Wildlife Area in Douglas County. See the Conservation section for WDFW's pygmy rabbit recovery effort.
For a map illustrating potential range and habitat distribution of this species in Washington, see the Statewide Wildlife Action Plan. For a map of worldwide distribution and other species' information, check out NatureServe Explorer.
The Columbia Basin pygmy rabbit is identified as a “Species of Greatest Conservation Need” (SGCN) under the State Wildlife Action Plan (SWAP). SGCN-classified species include both those with and without legal protection status under the Federal or State Endangered Species programs, as well as game species with low populations. The WDFW SWAP is part of a nationwide effort by all 50 states and five U.S. territories to develop conservation action plans for fish, wildlife, and their natural habitats — identifying opportunities for species’ recovery before they are imperiled and more limited.
The Columbia Basin pygmy rabbit is identified as a “Priority Species” under WDFW’s Priority Habitat and Species Program (PHS). Priority species require protective measures for their survival due to their population status, sensitivity to habitat alteration, and/or recreational, commercial, or tribal importance. The PHS program is the agency's main means of sharing fish and wildlife information with local governments, landowners, and others who use it to protect priority habitats for land use planning.
The Columbia Basin pygmy rabbit population is genetically distinct, considered to have been isolated for 10,000 years or longer from the rest of the pygmy rabbit population. Large-scale loss and fragmentation of shrubsteppe habitat were likely the primary factors contributing to decline, but once the population dropped below a certain threshold, other factors such as environmental events (extreme weather and fire), predation, disease, and inbreeding likely became threats.
Conservation actions needed to address these threats include protection and restoration of these habitats through landowner incentives, conservation easements, Safe Harbor Agreements, and acquisitions. Coordination is also necessary with U.S. Department of Agriculture (USDA) Farm Service Agency and Natural Resources Conservation Services and U.S. Fish and Wildlife Service (USFWS). Corridors of dense shrub cover connecting areas of suitable habitat are critical to recovery efforts.
Our Conservation Efforts
A major recovery effort is underway for this species. In 2001, with as few as 16 pygmy rabbits known to exist in Washington, the WDFW and the USFWS initiated a captive breeding program with the intent of reintroducing rabbits to the wild, but none of the pygmy rabbits from the first release in 2007 survived beyond the first year. Since 2011, thousands of pygmy rabbits have been released into the wild on Sagebrush Flat Wildlife Area in Douglas County and on The Nature Conservancy Preserve in the Beezley Hills in Grant County as a result of collaborative recovery efforts between WDFW, USFWS, the Oregon Zoo, Washington State University, other state wildlife agencies, Northwest Trek, The Nature Conservancy in Washington, and Conservation Northwest.
Initially, pygmy rabbits were reintroduced to Washington through captive breeding of purebred Columbia Basin pygmy rabbits, but due to a lack of genetic diversity in the remnant population likely from inbreeding depression, rabbits were later intercrossed with pygmy rabbits from populations outside Washington. In 2015, the reintroductions failed in the Beezley Hills Recovery Area for unknown reasons and failed again in 2017 due to wildfire, but reintroductions in the Sagebrush Flat Recovery Area are re-establishing a small wild population.
The majority of the wild pygmy rabbit populations occur on private lands owned by farmers enrolled in the USDA’s Conservation Reserve Program. Biologists continue to closely monitor released pygmy rabbits to collect data on breeding, habitat use, survival, mortalities, and other factors to modify reintroduction techniques and manage the rabbit population.
- Washington State Recovery Plan for the Pygmy Rabbit (1995)
- Amendment to the Draft Recovery Plan for the Columbia Basin Distinct Population Segment of the Pygmy Rabbit (USFWS - June 29, 2011)
- Periodic Status Review for the Pygmy Rabbit in Washington (2018)
- Status of the Pygmy Rabbit (Brachylagus idahoensis) in Washington (1993)