BILLINGS, Mont. (AP) — Federal wildlife officials have rejected a petition from advocates who sought to reclassify gray wolves as a threatened species in most of the U.S.

Gray wolves across most of the Lower 48 are classified as endangered, which is more protective than a threatened designation. Advocates hoped a change to threatened would pre-empt intervention from members of Congress who want to lift federal protections altogether.

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The U.S. Fish and Wildlife Service said in a Tuesday notice that the petitioners didn’t sufficiently back up their claims that wolves remain at risk due to disease and other factors.

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The petition was filed in January by more than a dozen groups including The Center for Biological Diversity.

Wolves in Minnesota already are listed as threatened. The animals are not federally protected in the Northern Rockies.

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