Thirty-one conservation and wolf-protection organizations, including the Wolf Conservation Center, sent a letter today urging the U.S. Fish and Wildlife Service to expeditiously release endangered Mexican gray wolves to the wild.

Adding new wolves from captivity to the struggling wild population is vital to diversifying the gene pool of the 113 closely related wolves in the wild in Arizona and New Mexico, the letter noted.

“Inbreeding could push the Mexican wolf over the cliff toward extinction if the Fish and Wildlife Service doesn’t release captive wolves soon,” said Michael Robinson, a conservation advocate at the Center for Biological Diversity. “The trail forward for successful recovery gets steeper and narrower every day that wolf families are kept behind wire mesh, when they could be helping fix the genetic crisis in the wild.”

Two specific packs should be freed this month, according to recommendations from a federal and state interagency Mexican wolf team. The team advised that releases occur in June or July after elk calves are born “to facilitate natural hunting behavior.” Conservationists want to ensure those wolves are not sequestered indefinitely in pens, as wolf families have been in previous years after release plans were shelved. Today’s letter recommends specific animals and release locations in southern New Mexico.

The conservationists requested that other wolves also be released, including a single female from Mexico, christened “Sonora” by schoolchildren in a naming contest, who was captured after crossing the border into Arizona in March. Freeing her in the United States to breed with wolves here would follow guidelines in the new draft Mexican Wolf Recovery Plan that calls for “translocations” of wolves between U.S. and Mexico populations to enhance both populations’ genetics.

Read more via Center for Biological Diversity.