World’s Smallest Rabbit Hops Into Oblivion

The smallest, and probably the rarest, rabbit in the world is on its last legs in the Pacific Northwest. The Columbia Basin pygmy rabbit thrived for thousands of years in the sagebrush steppe of what is now central Washington, but massive habitat loss has pushed the species to the brink of extinction.

This pygmy rabbit subspecies is already extinct, since the last purebred died in 2008, marking the end of its genetic bloodline. Biologists have since crossbred Idaho pygmies into the population, saving at least three-quarters of the unique Columbia Basin pygmy DNA, but have had mixed results with reintroducing the hybrid into the wild. 

One of the problems for the diminutive rabbit – which grows no bigger than a softball and weighs less than a pound – is that it has adapted too well to its environment. “Every last inch of a pygmy rabbit is built for sagebrush,” according to Smithsonian. “The enzymes in its gut evolved to neutralize the plant’s toxins and maximize digestion, and it tunnels elaborately beneath the sagebrush’s roots. It even forfeited its archetypal cotton tail, and thus blends in with the gray-green bushes.”

But in the last century or so, about 80 percent of the sagebrush in the Columbia Basin has been sacrificed to farms and ranchland. A lot of the remaining sage has gone up in wildfire flames in recent years. 

The Oregon Zoo – the first to successfully breed pygmy rabbits – has been involved in keeping the remnants of the genetic line alive. Without a healthy habitat, it's unclear where these little guys are supposed to live. The species is listed as endangered both federally and in Washington state.

Photo credit: Morgan Heim / Smithsonian Magazine