Maine’s rivers were once full of the salmon, but their population was decimated by overfishing, damming and environmental factors. They return only to a few rivers, and are protected under the federal Endangered Species Act.

The environmental groups, including Downeast Salmon Federation, the Maine chapter of the Native Fish Coalition, Friends of Merrymeeting Bay and several others, sent their request to the Maine Department of Inland Fisheries & Wildlife on Monday. They said the salmon belong protected by the Maine Endangered Species Act because “the only viable Atlantic salmon population in the United States is the Gulf of Maine distinct population segment.”