With endangered wild Atlantic salmon returning to Maine rivers in such low numbers, cormorants, which eat the migratory fish, are now in the crosshairs of federal regulators. They are looking for ways to reduce the numbers of the black birds, which are ubiquitous in rivers and estuaries, so that fewer salmon will be eaten. An extreme solution would be to begin killing cormorants, which are protected under a different federal law. Such a solution should wait until other options are exhausted.

It is well documented that cormorants kill and eat many fish near dams. Dams impede the fish from going upstream or downstream, causing them to congregate, making them more susceptible to predators. Dams and their accompanying buildings and structures also provide ideal perches where the birds wait and spy approaching meals.

There are efforts under way to remove dams on the Penobscot and other rivers. Short of these major undertakings, simply removing or submerging old cribwork, large rocks and other places where cormorants perch may be helpful.

In the larger picture, restoring rivers – whether done by removing dams, reducing pollution or rebuilding habitat – for all fish species will benefit the endangered salmon. In some rivers, young salmon heading out to sea in the spring are often the only fish in the water. These smolt make easy targets for cormorants. If alewives, shad and other fish were running at the same time as the young salmon, these fish could better hide and the cormorants would have other choices for dinner.

A more troubling question is where does the predator control stop.

Cormorants eat about 1 pound of fish (a quarter of their average 4-pound body weight) each day. They prefer small fish in shallow water. A harbor seal typically eats 13 pounds of fish per day. Should they be killed?

Last year, some in Washington cheered an unusually long stay of an orca whale pod in the Hood Canal. The 11 whales, which normally stay in the area only a short time, remained longer and biologists estimate ate 50,000 pounds or one-third of the area’s harbor seals. Biologists surmised this could be good for salmon recovery in the Pacific Northwest, although the seal population will eventually rebuild.

Pitting one species against another is not the solution to Maine’s salmon woes. Improving habitat for salmon, and other fish, may aid their return. Or, if as some scientists believe, global climate change is eliminating salmon from the southern, and warmer, end of their range, cormorants don’t have much to do with the fish’s demise.

Before any decisions are made to eliminate the birds, a lot more study is needed.