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The U.S. Fish and Wildlife Service says it will consider whether to list the lake sturgeon as an endangered or threatened species.

The agency said Wednesday there is "substantial information" to justify a study of whether the should receive federal protection.

Lake sturgeon are members of a family of fish that reach back to the dinosaur era. Their range extends from Hudson Bay to the southern Mississippi River. They are the largest native freshwater fish in the Great Lakes.

Their numbers were once in the millions but have fallen drastically in the past century because of pollution and overfishing.

The Fish and Wildlife Service also said it would consider changing the Gila topminnow's status from endangered to threatened. It rejected a proposal to protect the Siskiyou Mountains salamander.