Columbia Basin pygmy rabbits are facing extinction

The unique species depends on a healthy shrubsteppe habitat. Wildfires are decimating it

Eerie feeling: Only about 120-150 Columbia Basin pygmy rabbits remain. Photo: WDFW

By K.C. Mehaffey. July 25, 2024. Jonathan Gallie knew a wildfire was burning near his most productive Columbia Basin pygmy rabbit habitat.

But the Pearl Hill Fire that started over Labor Day weekend in 2020 appeared to be heading the other way. Firefighters were aware of the rabbits’ location and were hopeful about protecting them.

But while Gallie was out picking pears with one of his daughters, he noticed an ominous plume of smoke.

“I got into cell range and my phone blew up. Then I looked at the fire map and my heart just kind of sank,” he says.

As the Washington Department of Fish and Wildlife’s pygmy rabbit recovery coordinator, Gallie later confirmed, “Everything we had been working on was wiped out in a matter of hours.”

The wildfire near Brewster, Wash., killed at least 70 endangered pygmy rabbits and destroyed some of their prime habitat.

It was a major setback in the agency’s 20-year effort to pull this tiny rabbit off the edge of extinction.

Nearly four years later, Gallie says the recovery program still hasn’t clawed its way back to where it was before the fire.

Now WDFW’s regional nongame biologist, Gallie says climate change didn’t send this rabbit into a tailspin. But to the extent that it’s causing more frequent and severe wildfires, climate change may contribute to the rabbit’s final demise.

Whether it’s climate-driven or not, “Ultimately, wildfire is going to be the make-or-break for this species,” he says. “It’s a race against time.”

More than 20 years after wildlife biologists caught some of the last remaining Columbia Basin pygmy rabbits and began a captive breeding program, the future of this genetically-distinct population of pygmy rabbits now depends on between 120 and 150 rabbits living in the wild and in semi-wild breeding enclosures in two areas.

The Washington State recovery plan for pygmy rabbits calls for an average of 1,400 adult rabbits over five years, spread across six different areas.

Although they’ve come a long way in the last two decades, the state agency acknowledges it’s still far from that goal.

The Washington Fish and Wildlife Commission will decide in August whether Columbia Basin pygmy rabbits will remain on the state’s endangered species list.

WDFW’s draft periodic status review of the rabbit—co-written by Gallie—says that they should.

Climate change, wildfires to blame

Pygmy rabbits are considered highly sensitive to climate change, largely due to the devastating impact that wildfires have on shrubsteppe habitat.

“This rabbit is predicted to undergo a major decline in geographic range as a result of climate change, which is expected to bring warmer, drier conditions, including drought, to Washington’s Columbia Basin where the species occurs,” according to the Washington Department of Fish and Wildlife.

Climate change, the agency says, is also expected to bring larger, more frequent and hotter wildfires.

The good life: Healthy shrubsteppe in Washington. Photo: WDFW

After a significant fire, shrubsteppe is often replaced by cheatgrass and other invasive plants for years, if not decades.

Still, if the state’s efforts to recover these rabbits fails, Gallie isn’t so sure he’d blame climate change.

“I’d blame fires. That’s the direct cause,” he says. “Not only do they eliminate the very limited shrub-steppe habitat, but they also kill the rabbits. So the fire hits us at both ends.”

Pygmy rabbits are North America’s smallest species of rabbit. Weighing only about a pound, they completely rely on Washington’s disappearing shrubsteppe habitat.

And not just any shrubsteppe will do.

These rabbits need tall, densely packed brush to protect them from predators.

They need the sage plants, which are virtually their only source of food in winter.

And they need relatively deep, loose soil to dig their burrows—the only rabbit native to North America that does so.

Gallie points out that pygmy rabbits have a very limited range, and any species with such specific habitat needs doesn’t have much ability to handle change.

After a severe fire, the habitat won’t be suitable for at least 15 to 20 years—many pygmy rabbit generations, given their three-year lifespan.

If the rabbits don’t recover, it will be difficult to pinpoint a reason.

Not so good: Aftermath of the 2020 Pearl Hill Fire. Photo: InciWeb

Climate change, human activity, land conversion, disease and the spread of invasive species that facilitate fire spread are all interrelated, and among the challenges this tiny mammal is facing.

Regardless of what could cause its ultimate demise, development and the conversion of shrubsteppe habitat into farmland has put them on a precarious path.

“I think in this case, it’s much easier to point to the direct loss correlating with their preferred habitat declining,” says Gallie. “In other states, like Idaho—where expansive shrubsteppe still remains—pygmy rabbits are still fairly abundant.”

In Washington, though, most of the rabbit’s preferred shrubsteppe was lost to agriculture or development some 50 to 100 years ago.

But farmers are now aiding in pygmy rabbit recovery.

Roughly two-thirds of the rabbits now living in the wild are on private lands enrolled in the voluntary Conservation Reserve Program, a federal program that pays farmers to remove environmentally sensitive land from agricultural production.

That’s important, says Gallie, because the best shrubsteppe habitat for the rabbits has the deepest soil—which were the first places to become farmland.

“Of the 10.4 million acres of shrub-steppe that existed in Eastern Washington before European settlers arrived in the mid-19th century, only 20% remains. Many areas with deep-soil shrubsteppe … were the first to be converted to agriculture,” according to WDFW.

Roller-coaster recovery

Gallie agrees that the state’s recovery efforts over the past 20 years have been marked by a series of successes followed by significant setbacks.

“It is very much a roller coaster. The successes are extremely rewarding and pretty euphoric, and the losses are extremely heart-wrenching and difficult to handle,” says Gallie.

Columbia Basin pygmy rabbits were once distributed across five Washington counties, but by 1997, they could be found in only six isolated populations in Douglas and Grant counties, and by 2001, only one population remained.

Ready to go? Jon Gallie holds a pygmy rabbit kit before it’s released to the wild. Photo: WDFW

In May of that year, WDFW caught 16 Columbia Basin pygmy rabbits and brought them to captive breeding facilities at Washington State University and the Oregon Zoo.

It was a last-ditch effort to protect them from the stress of living in a rapidly changing environment and to see if their breeding success could improve.

A genetic analysis had found their genetic diversity was critically low and that the remaining rabbits were heavily inbred. Survival chances were poor due to the poor genetic composition.

Gallie says that the initial captive breeding effort failed to produce enough kits to begin releasing them in the wild, “indicating it truly was an inbreeding situation where not enough genetic diversity was left in the rabbit population.”

So began the first of three translocation operations that involved moving Great Basin pygmy rabbits from Oregon, Idaho, Wyoming and Utah and cross-breeding them with the few remaining Columbia Basin rabbits.

Gallie says Columbia Basin pygmy rabbits are not a separate species or subspecies, but are genetically distinct from Great Basin pygmy rabbits.

Fossil evidence indicates they were separated from the Great Basin pygmies some 10,000 years ago, with the closest pygmy rabbits in central Oregon, about 125 miles away.

The first crossbreeding program occurred from 2003 to 2011.

It was successful at introducing more genetic diversity into the population, but survival rates declined—primarily due to disease—and ultimately it, too, didn’t produce enough offspring for large-scale reintroduction.

But since 2011—when the agency transitioned to a semi-wild captive breeding program—the recovery effort has produced a total of 2,547 kits and released 2,230 of them into the wild.

Beginning in 2011, the first iteration of semi-wild captive breeding involved fencing in six- to 10-acre reserves in the rabbits’ former territories and attempting to prevent predator losses.

Predation is the main cause of pygmy rabbit mortality in the wild, where 42 to 70% of juvenile bunnies are killed by coyotes, weasels, owls and other birds.

In addition to fencing out coyotes and discouraging birds of prey, the recovery team brought in more Great Basin rabbits to again bolster the population and genetic diversity.

“Kit production and rabbit releases increased substantially through 2015 before dramatically declining in 2016 due to disease (coccidia) in enclosures,” according to the status report.

So in 2017, the agency transitioned its recovery again—this time with mobile enclosures. Fenced-in areas were reduced to three acres, which are relocated every two or three years to reduce the chances of disease or invasive weed growth.

Another group of Great Basin rabbits was added to the breeding enclosures in the spring of 2020.

But that fall, the Pearl Hill Fire struck.

It killed all of the breeding rabbits in the Burton Draw recovery area and all of the rabbits that had been released into the wild nearby. It also burned all of their potential habitat, rendering it completely uninhabitable for pygmy rabbits.

“It was a very traumatizing ordeal for all of us,” says Gallie.

Of the three recovery areas, the Burton Draw population had been growing the fastest. WDFW was finally seeing some real expansion, but the fire took away 40% of everything they had built, including two of its four breeding enclosures.

“Even four years later, there’s probably not a week goes by that I don’t pause for a moment and ask, ‘Why? And where would be have been if that had not happened?’” says Gallie.

This wasn’t the first wildfire to impact the pygmy rabbit recovery program, but it was the most devastating.

“It set us down a track where its been harder and harder to manage that system, and now we have less flexibility to handle changes,” says Gallie.

Columbia Basin pygmy rabbits are now reduced to two populations.

Still, Gallie is optimistic about the potential for success.

“For the most part, I feel like when we don’t have a catastrophic wildfire or an unanticipated disease, we’ve had a pretty good track record of reintroducing rabbits into those sites. Now, it’s just a question of whether we can outpace the wildfires and get them in enough areas before we lose more,” he says.

Can the pygmy rabbit survive?

The Pearl Hill Fire hit just when WDFW had found its way to the most successful recovery strategy to date.

Gallie—who headed the Columbia Basin pygmy rabbit recovery effort from 2016 through 2023—says it was a bare-bones “survival of the fittest” method that basically just fenced out coyotes and captured the juveniles to release in new areas.

Yet juvenile survival rates have been as high as 40%, he says.

That isn’t the average. Survival rates can drop as low as 5% some years.

But releases from the mobile enclosures were averaging 23-30% survival, which was helping the wild rabbit population grow.

In the wild, juvenile survival is about 10%.

Before going to the mobile enclosures, survival rates were similar to wild survival—about 8-12%.

The agency reached its goals by raising and releasing more rabbits.

More than rabbits: Washington’s shrubsteppe is home to a variety of species, burrowing owls among them. Photo: WDFW

Gaille says pygmy rabbit populations are by nature extremely volatile. Their numbers can double or triple in one calendar year.

“They truly do breed like rabbits when conditions are best,” he says.

But when conditions are poor—like in a drought year—populations can decline by 90% in a single year.

The difference is based on how many kits a female has in its three litters each year.

When environmental conditions are good, a pygmy rabbit can produce 15 to 20 kits a year, he says. When they’re poor, she may have only a few kits.

And because they live for only a few years, a single year’s survival rates can make a big difference in the population.

Gallie says because pygmy rabbits are a short-lived species, biologists quickly learned not to make too much of their successes—or their losses.

“The short lifespan just is what it is. It’s the nature of this little beast. But it does allow for rapid increases and rapid declines. We try to buffer our decreases and maximize our declines,” he says.

To that end, the agency is preparing for more devastating wildfires.

Fires aren’t only likely; they’re expected.

“We kind of sit on pins and needles all fire season, hoping today is not the day,” says Gallie.

Before the next big fire, they need more time to establish pygmy rabbits in new areas.

“Right now, we’re scoping out the next three areas we want to reintroduce rabbits within the Columbia Basin. We want to spread out the rabbits so that any one particular fire does not hit us so bad,” says Gallie.