SPOKANE – An emergency effort to save endangered Columbia Basin pygmy rabbits will get its first test next week when state and federal scientists release nearly two dozen of the animals back into their native habitat in north-central Washington.

The rabbits that will be released Tuesday are the product of an emergency roundup six years ago of the remaining pygmy rabbits in the region, who were put into a captive-breeding program in a last-ditch effort to increase their numbers.

“This is the first reintroduction, so it’s a learning process,” said Tom Buckley of the U.S. Fish and Wildlife Service in Spokane. “We want to see how they react to the wild coming out of a captive breeding environment.”

About 23 pygmy rabbits will be released on a state wildlife area in Douglas County. The rabbits will be placed in artificial burrows for cover until they dig their own burrows, and will wear tiny radio transmitters around their necks, to allow biologists to monitor their movements.

“We’re committed to preventing the loss of the pygmy rabbit from our state’s diverse wildlife heritage,” said Jeff Koenings, director of the Washington Department of Fish and Wildlife. “Extinction is not an option.”

More than 70 pygmy rabbits will remain in the captive breeding program to provide animals for future releases. The program has placed breeding rabbits at the Oregon Zoo, Northwest Trek near Tacoma and at Washington State University in Pullman.

The Columbia Basin pygmy rabbit is the country’s smallest native rabbit, according to a press release from the state and federal agencies. It was listed as a state endangered species in 1993.

By 2001, there were fewer than 40 pygmy rabbits left in the Sagebrush Flat area of Douglas County. In 2003, the Columbia Basin population was federally listed as an endangered species.

Biologists for the state captured 16 of the remaining Columbia Basin rabbits in 2001 and 2002. Captive breeding started in 2002.

Efforts to breed rabbits solely from Columbia Basin stock were unsuccessful. Biologists believe the rabbits decline in population may be caused in part to genetic inbreeding that occurred as numbers dwindled in the wild.

In 2003, Washington pygmy rabbits were crossbred with Idaho pygmy rabbits.

“We tried to breed rabbits solely from Columbia Basin stock, but they did not produce enough healthy offspring to allow for re-establishment into the wild,” said Fish and Wildlife biologist Dave Hays.

The rabbits being released have approximately 75 percent Columbia Basin ancestry, Hays said.

That percentage could increase in future years as additional animals with a higher percentage of Columbia Basin parentage are reintroduced to the wild, said Ken Warheit, Fish and Wildlife geneticist.