The pygmy rabbit (Brachylagus
idahoensis) is the smallest rabbit in North America and is able
to fit in the palm of a hand. It is patchily distributed in the
sagebrush-dominated areas of the Great Basin, which includes
portions of Oregon, California, Nevada, Utah, Idaho, Montana, and
Wyoming. An isolated subspecies of pygmy rabbit found in Washington
State is near extinction.
Relatively little is known about this
species, and scientists are still trying to figure out how best to
estimate their population size. However, one thing we do know is
that pygmy rabbits are closely associated with tall, dense stands of
big sagebrush growing on deep, loose soil. Its dependence on
sagebrush is the main reason for its decline.
Unlike all but one other North
American rabbit, the pygmy rabbit digs its own burrows in deep,
loose soil. Its burrow systems are typically constructed under
clumps of big sagebrush and pygmy rabbits usually stay within a 100
foot radius of the burrow. Not only do they rely on sagebrush for
shelter and protection from predators, but they depend on sagebrush
for food. About 98 percent of their winter diet is composed of
sagebrush and a good portion of their spring and summer diet is as
well. They sometimes climb into tops of sagebrush to feed.
pygmy rabbit is distinguishable from other rabbits by its small
size, short ears, gray color, and small hind legs. Unlike the
cottontail rabbit, it lacks white fur on the underside of their
tail. It also has white ear margins, a characteristic that
distinguishes it from a cottontail. Pygmy rabbits are active
throughout the year in day or night, mainly at dusk and dawn.
Pygmy rabbits are preyed upon by
weasels, coyotes, badgers, bobcats, birds of prey, owls, foxes, and
sometimes humans (pygmy rabbits are sometimes difficult for hunters
to distinguish from other rabbit species). Mortality is high for
juveniles (one study found that 50 percent did not survive the first
five weeks) and adults alike, and populations may experience an
annual mortality rate up to 88 percent. Like other rabbits, pygmy
rabbits mainly try to stay hidden and are cryptically colored to
avoid predation. Although capable of short bursts of speed, pygmy
rabbits are vulnerable to predators if caught in the open. They do
not generally leap like other rabbits, but move by scampering close
to the ground. This behavior helps them to avoid predators as they
move rapidly through dense cover.
Because so much sagebrush habitat has
been degraded or destroyed over the past 150 years due to
agriculture and other human development, wildfires, and invasion of
noxious weeds, many fear that pygmy rabbit numbers have declined
drastically. However, it is difficult to know with certainty what
their current status is because until recently wildlife agencies put
little or no resources towards monitoring pygmy rabbit populations.
In September, 2010, the U.S. Fish and Wildlife service determined
that there is not enough evidence to warrant listing pygmy rabbit as
threatened or endangered under the Endangered Species Act. Letís
hope that this decision spurs land users and wildlife agencies to
take actions now to conserve quality sagebrush habitat and monitor
pygmy rabbit populations so that this species will never have a need
to be listed.