Jim Clark/U.S. Fish and Wildlife Service

A Mexican gray wolf.

PHOENIX — The Arizona Game and Fish Department is suing the federal government to force it to develop an updated recovery plan for endangered Mexican gray wolves.

The lawsuit filed Monday is aimed at forcing the U.S. Fish and Wildlife Service to publish a plan that includes guidelines for when the wolves can be removed from the endangered species list. Without those criteria the agency said the wolf could never be delisted.

The state is already involved in litigation in an effort to block plans to allow Mexican wolves to populate larges areas of Arizona that the agency says are not part of its historic range.

A survey released in February showed 109 wolves in Arizona and new Mexico, more than at any time since a re-introduction program began in 1998.

MORE: Why 'Success' Of 1 Female Mexican Gray Wolf Creates Problems For The Entire Species