The Center for Biological Diversity and four other groups filed their suit Monday in federal court in Washington.
They contend the U.S. Fish and Wildlife Service acted too hastily last month when it removed federal protections from the estimated 4,000 wolves in Michigan, Minnesota and Wisconsin.
The wildlife agency says the wolves have recovered from the brink of extinction and are capable of surviving under state management.
Opponents also sued earlier this month over the government's removal of wolves in the northern Rockies from the endangered list.
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