(AP) -- Rabbits are certainly known for their propensity to multiply, but one species of jackrabbit is having trouble keeping up. There are an estimated 150 white-sided jackrabbits left in the United States, and federal wildlife officials announced Wednesday they will study the elusive rabbit to determine if it needs to be protected under the Endangered Species Act.
It's not lack of libido that's holding back the white-sided jackrabbit.
The U.S. Fish and Wildlife Service says the biggest threat is change to the rabbits' habitat brought on by drought, grazing, the suppression of wildfire and the encroachment of shrubs into the Chihuahuan grasslands of New Mexico's bootheel - the only place in the United States where the jackrabbit has been documented. Wildfire helps keep shrubs in check and revitalizes grasslands, which the rabbits depend on.
The rabbit also lives in Mexico, and those populations have also declined, said Nicole Rosmarino, a biologist with the Western environmental group WildEarth Guardians.
Rosmarino said the existing pressures on the white-sided jackrabbit likely will worsen. Forecasters predict extended and more-frequent periods of drought in the Southwest because of climate change.
The Fish and Wildlife Service says it's uncertain how climate change will affect the jackrabbit and its habitat, but it plans to look more closely at the potential impact during its 12-month review.
After the review, the agency will decide whether the rabbit warrants protection as an endangered or threatened species. In New Mexico, the rabbit has been listed as a state endangered species since 1975.
"The rabbit has cleared the first hurdle toward federal protection, so that's good news," Rosmarino said.
The Fish and Wildlife Service's decision to review the rabbit is the result of a petition and lawsuit filed by environmentalists.
The rabbit's name comes from a conspicuous white area along its body, most noticeable when the rabbit runs. The jackrabbits, usually seen in pairs, mate for life. While they can produce several litters a year, the litters are usually small - between one and three young.
The rabbit's large ears and long limbs are disproportionate to its body, creating more surface area to help the animal dissipate the heat that's part of living in the desert.
Besides the white-sided jackrabbit, WildEarth Guardians is seeking protections for other species, including the Sonoran desert tortoise. The Fish and Wildlife Service has yet to issue a finding on that species, but WildEarth Guardians says the tortoises' numbers have also been cut in half in recent decades.
As Rosmarino points out, Wednesday's decision by the agency puts the rabbit ahead of the tortoise, in both species' race to avoid extinction.
On the Net:
WildEarth Guardians: http://www.wildearthguardians.org
U.S. Fish and Wildlife Service: http://www.fws.gov
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