Washington’s pygmy rabbits face challenges in their continued recovery • Earth.com
Agriculture, overgrazing, development and invasive species have destroyed more than half of Washington habitat of Columbia Basin pygmy rabbits.

Washington’s pygmy rabbits face challenges in their continued recovery

To most, rabbits are just rabbits. To those who think for a moment, there are obviously wild rabbits and the domesticated variety found in pet and farming supply stores. In reality, rabbits and hares collectively make up family Leporidae which contains roughly 62 species.

Wide Open Spaces reports that there are 15 species of rabbits and hares in North America alone. There are jackrabbits and cottontails, of course. There is also the snowshoe hare that changes its coat to suit the season. Then, there is the smallest rabbit in North America, the pygmy rabbit (Brachylagus idahoensis).

Pygmy rabbits as a species can be found throughout sagebrush habitats (sagebrush makes up most of their diet) in the Great Basin, found in parts of California, Idaho, Montana, Nevada, Oregon, Utah, Washington and Wyoming.

Washington’s pygmy rabbits are separated geographically from the rest of the species, and so are special in their own right. Fossil evidence suggests that the Washington pygmy rabbits have been separate from the other pygmies for thousands of years but were once much more widespread across the state, according to the Washington Department of Fish and Game.

Because of their unique geography, the pygmy rabbits of Washington state are referred to as Columbia Basin pygmy rabbits. Recent research shows that the Columbia Basin pygmy rabbit have been genetically isolated from other pygmy rabbits for at least 10,000 years, but their isolation made them vulnerable as well as unique.

By 1990, Washington State listed their pygmy rabbits as threatened, and then in 1993 they were reclassified as endangered. The US Fish & Wildlife Service reports that by 2001 the entire pygmy rabbit population of Washington State was thought to consist of a single rabbit colony of less than 50 individuals. By 2004, the Washington pygmy rabbits were extinct in the wild. Fortunately, the rabbits still remained alive as a species in captivity, awaiting a comeback.

Nature Conservancy Magazine reports that in 2001, all of the pygmy rabbits that could be found in Washington were captured, a mere 16 individual rabbits. Unfortunately, initial captive breeding didn’t go well for the little rabbits, so after long consideration, closely related rabbits were introduced into the Columbia Basin pygmy rabbit gene pool. Idaho pygmy rabbits were included in the breeding program, while biologists still carefully maintained 75% of genetics from the Columbia Basin pygmy rabbits.

The new rabbits increased birth rates and the program was successful enough that 20 rabbits were released on land owned by Washington state in 2007. All 20 of the initially reintroduced rabbits were killed by predators. Since that time, the breeding has been converted to a semi-wild breeding program with rabbits kept outside in a predator fenced enclosure, supplied with water and sometimes rabbit food (allowing them to also eat natural vegetation). Between 2011 and 2016, almost 1,800 rabbits have been released into the wild.

The future for the Columbia Basin pygmy rabbits is far from certain though. High Country News reports that in 2016, reproduction dropped in the captive rabbits by 75% and disease increased. These downfalls have lead to the methods of captive rabbit breeding being tweaked and rabbit numbers have continued to climb but this in itself leads to a conundrum.         

Unfortunately for the rabbits being bred in captivity, there isn’t a lot of home left for them to come back to. Washington’s shrub-steppe a mix of sagebrush and grasslands is a shattered fragment of what it once was. Agriculture, overgrazing, development and invasive species have destroyed more than half of the shrub-steppe Washington once had. The Sage Grouse Initiative reports that nationwide, only 56% of sagebrush habitat remains in the US. A scientific paper revised in 2013 found that, of the original 24,437 square miles of sage-steppe habitat in Washington state, only 46.3% remains, 98% of it being destroyed by cropland agriculture.

There are other major threats to the fragile rabbits as well. High Country News reports that in 2017, a 30,000 acre fire in Washington wiped out most of the rabbits in the area. With such small populations, freak occurrences like fires can hurt the Columbia Basin pygmy rabbits more than it otherwise would. The frequency and intensity of fires in the area are also driven partially by large amounts of flammable invasive cheatgrass, changing the natural fire dynamics of Washington’s sage-steppe. Hotter, drier summers also increases the likelihood of fires.

Unfortunately, the reintroduction sites of the Columbia Basin pygmy rabbits are separated from each other by a tangle of houses, roads and fields, preventing the individual reintroduced populations from connecting. The Nature Conservancy and US Department of Agriculture pay farmers to take land out of production to be used by wildlife, a measure that may help the rabbits. Despite the hardships the rabbits continue to face, their population grow slowly and precariously.

Columbia Basin pygmy rabbits are important for the land they live in. The rabbits create burrows which in turn help the soil maintain its health. Ideally, an abundance of rabbits would also supply food for an abundance of wildlife like coyotes and raptors. Burrowing owls may use old rabbit burrows as their own homes. In a completely intact sage-steppe ecosystem, the pygmy rabbits would be joined by animals such as wolves and bison, playing a small role in an ancient drama, completing the picture of an American Serengeti.

For many though, this is part of a fanciful dream, not the reality of future ‘progress’ of agriculture and real estate development. This dichotomy of ideas is a schism between minds. There is little reason the rabbits will make a person’s life better in any tangible way. Instead, the reason to protect pygmy rabbits or any species is a reason of morality and passion based on experience. To watch an animal in the wild closely is to glimpse a whole world of experiences, reflexes, even thoughts un-knowable by the human mind. Columbia Basin pygmy rabbits are part of the great unknown mystery of the world we call wild and that in itself is enough reason to protect them.         

By Zach Fitzner, Earth.com Contributing Writer    

Image Credit: Shutterstock/Randy Bjorklund

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