(AP) -- American wildlife officials and ranchers are raising questions over a plan to release a rare North American gray wolf to its historic range in northern Mexico: Will it stay south of the border and what can be done if it threatens livestock?
The U.S. Fish and Wildlife Service said this week it learned of the plan to release captive-bred Mexican gray wolves during a meeting with Mexican officials.
A male, female and two yearlings could be released in Sonora state, bordering Arizona and New Mexico, as early as October. Another release is planned for December and more could happen next year as part of an effort by both countries to return the wolves to the wild.
"I think we kind of assumed it would happen eventually but we didn't realize it was going to happen this quickly," said Charna Lefton, regional spokeswoman with the Fish and Wildlife Service in Albuquerque.
The Mexican agency that oversees natural resources and the environment, known as SEMARNAT, did not immediately respond to telephone and email requests for comment.
While wildlife officials and conservationists generally support the move, Lefton says "everyone is asking the same questions."
What if the wolves cross into the United States? Will they be protected under the federal Endangered Species Act? Or will they have the same "nonessential, experimental" designation as wolves released as part of a reintroduction effort in New Mexico and Arizona?
The Fish and Wildlife Service has posed those questions to the agency's attorneys and are hoping for answers in coming weeks. The agency also plans another meeting with Mexican officials.
The Mexican wolf, a subspecies of the gray wolf, was exterminated in the wild in the Southwest by the 1930s after a campaign by the federal government to control the predator.
A handful of wolves were captured in Mexico in the late 1970s to save the animal from extinction. In 1998, the U.S. government began reintroducing wolves along the Arizona-New Mexico line in a 4 million-acre territory. Biologists had hoped to have at least 100 wolves by now, but recent surveys show about half that. It's unclear how many wolves are in Mexico's Sonora state.
The wolves in Arizona and New Mexico do not have full protection under the Endangered Species Act because they are designated as "experimental," giving game officials greater flexibility to manage them and even allows permanent removal - by capturing or killing - after three confirmed livestock kills in a year.
Conservationists contend any wolves found outside the reintroduction area in the two states would be protected under the Endangered Species Act unless the Fish and Wildlife seeks a contrary rule.
Wolves returning to the wild in Mexico only complicates a troubled effort in the United States, especially if the animals cross the border, said Caren Cowan, executive director of the New Mexico Cattle Growers' Association.
"You've got the potential of wolves coming down on you from the north that have one endangered status, and you've got wolves coming from the south that may have a different status," she said. "How are you supposed to tell the difference?"
Conservationists are encouraged by Mexico's plans, saying more wolves in the wild will help ensure species survival. If the U.S. and Mexico populations mingle, that would bolster the animal's limited genetic pool.
U.S. Fish and Wildlife Service Mexican gray wolf recovery program: http://www.fws.gov/southwest/es/mexicanwolf/
New Mexico Cattle Growers' Association: http://www.nmagriculture.org/
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