By Laura Zuckerman
(Reuters) - Rare wolves in the American Southwest will be allowed more room to roam but some could be marked for death if they prey too heavily on elk and deer prized by hunters, under a rule issued by federal officials on Monday.
The rule revising management of the fewer than 100 wolves in Arizona and New Mexico stems from legal challenges by the non-profit Center for Biological Diversity, which argued U.S. wildlife managers failed to properly protect the so-called Mexican wolf.
The federal government's new management plan for the endangered Mexican wolf, which is one of the most imperiled mammals in North America, enlarges the acreage it can occupy without relocation and expands the area where captive wolves can be released into the wild, according to a statement from the U.S. Fish and Wildlife Service.
U.S. wildlife officials also declared the Mexican wolf was a separate subspecies to the gray wolf found elsewhere in the United States. That ensures Mexican wolves would not be included in a proposal by U.S. President Barack Obama's administration to remove gray wolves in states outside Alaska from the federal endangered and threatened species list.
The Fish and Wildlife Service ruled that 300 to 325 Mexican wolves would be needed in the U.S. Southwest for the animals to be considered recovered and stripped of protections under the federal Endangered Species Act.
Conservationists argued the revisions were still insufficient to guarantee the Mexican wolf would make a strong comeback and said a minimum of 750 were needed for the animal's long-term survival.
They also took aim at a rule unveiled on Monday that gives the U.S. Fish and Wildlife Service more leeway to allow state wildlife agencies and others to kill Mexican wolves.
The rule change would allow such killing of the predators to protect livestock and other domestic animals or to prevent what the service called "unacceptable impacts" on elk and deer herds valued by hunters.
"This is very worrisome," said Michael Robinson, conservation advocate with the Center for Biological Diversity. "These wolves were subjected to a ruthless extermination campaign to the point where they nearly went extinct."
(Reporting by Laura Zuckerman in Salmon, Idaho; Editing by Alex Dobuzinskis and Paul Tait)