America’s tiniest rabbit is hopping back home

GRANT COUNTY — If, while hiking through certain stretches of sagebrush in northern Grant County, one were to see a silent flash of brown in the underbrush, it might be the continent’s smallest species of Leporidae, the pygmy rabbit.

More likely than not, a passerby would see nothing, even as they walked inches above their burrows — and unlike other species of rabbit, some of which steal the burrows made by more industrious creatures, the pygmy rabbit is the only one of its kind that digs its own. The quiet creatures, weighing at most 16 ounces, are nearly invisible to those who don’t know what they’re looking for.

And only a few decades ago, the Columbia Basin subspecies, isolated from others of its kind for at least 10,000 years, nearly invisible in their preferred habitats, had all but disappeared.

Once found throughout North Central Washington from Okanogan to Adams counties, by 2001, the last remaining population in Douglas County was blinking out of existence, said Jon Gallie, Wildlife Biologist with the state Department of Fish and Wildlife.

So, in 2002, the remnant pygmy rabbits were captured and sent to Washington State University and the Oregon Zoo to begin a last-ditch captive breeding program, Gallie said.

Increasing the population’s numbers wasn’t the only problem that breeders faced. Inbreeding over generations had damaged the group’s genetic diversity, so greatly had the population dwindled since the introduction of modern farms to the deep soils preferred by the species.

So, just like cougars were once brought in to interbreed with the last true Florida panthers, subspecies from as far as Wyoming were flown in to assist in the breeding effort.

“All of the rabbits in the enclosures are like a melting pot of the breeds from across the nation,” Gallie said. “A bit of a blend.”

This approach had to be handled delicately, Gallie said — too little breeding with outside populations, and the Columbia Basin variety was susceptible to disease and other ill effects of poor genetic diversity; too much, and the native rabbits would lose the genetic uniqueness it had adapted over millennia to help it survive.

“Over time we’re able to ease that off, and we only do that every so often,” Gallie said. “You want to bring in just enough to replace the inbreeding deficiencies, but you don’t want to bring in too much such that local populations get swamped out.”

But even with numbers on the rise, reintroduction of the miniature mammal back to its ancestral home required a home to return to. Without rehabilitating some of the habitat that had been lost, the rabbit would eventually hop back to square one.

Around a decade ago, the State Acres for Wildlife Enhancement, or SAFE, program was added to the decades-old Conservation Reserve Program, or CRP. Through that program, a part of the massive agricultural fund Farm Bill, landowners are paid yearly rents to convert marginal agricultural land — typically wheat acreage, in Central Washington — into natural habitat, planting native seeds and flowers with help from state departments of fish and wildlife.

Unlike conservation easements, which can last into perpetuity, landowners retain long-term control over their land, making it a more popular option for conservation groups, said Michael Rickel, Private Lands Manager with the state Department of Fish and Wildlife. Farmers receive reliable money, stay involved in the management of their land, and also get to watch as a long-gone species takes root after a long time away, Rickel said.

“Those landowners like to see those species on their land,” Rickel said. “Every day is Earth Day for a farmer.”

Between Douglas County and northern Grant County, around 200,000 acres of land has been set aside through incentives like the SAFE program, Gallie said, giving the department space to reintroduce species like the pygmy rabbit. In 2010, the first enclosures were built, fencing in a few dozen of the tiny critters in open acreage where they would be safe from land predators like coyotes.

“We keep some breeding adults more or less operating as a furry hatchery,” Gallie said. “With some extra comforts and not having to dodge as many predators, they’re able to pump out much more young than their counterparts.”

It’s the offspring of those rabbits, which can have up to four litters a year, that then get taken out of the enclosures and allowed to make their way inside of three designated recovery areas a good ways north of Quincy and Ephrata.

There, they burrow and feast on sagebrush — enough of the typically toxic plant in proportion to its body weight to kill most other critters, Gallie said.

“They’re the smallest rabbit species in North America, and they’ve adapted to survive on one of the harshest plants out there,” Gallie said.

Recovery efforts in the last decade have trended in the right direction, but it has at times been a roller coaster, Gallie said. Unlike larger, longer-lived species, where populations grow slowly but steadily with conservation efforts, the pygmy rabbits live only about three years, and disruptions can have a huge impact on their numbers.

For years after the semi-captive breeding programs in enclosures began, populations doubled roughly every two years, Gallie said — massive increases for any recovery effort. But the reverse is also true: after a large wildfire swept through the Beezley Hills recovery area in 2017, much of a breeding enclosure there was destroyed, setting back recovery efforts in that area by two years, Gallie said.

Now, the department is considering ways to mitigate risk to future natural disasters of that kind, including by spreading out where the rabbits are reintroduced. That runs its own risks, as smaller populations can more easily be wiped out and don’t multiply as rapidly, so there’s a balance to be struck, Gallie said.

“But overall, we’re headed in the right direction,” Gallie said.

Emry Dinman can be reached via email at edinman@columbiabasinherald.com.