At a time when Maine is removing dams and returning rivers to a more natural state, in part to boost local fish populations, it is odd that the state continues to intentionally block native fish from returning to the St. Croix River. Lawmakers have a chance to improve the situation with LD 1957, which would allow alewives to return to a portion of the river.

By opening part of the river that forms the border between Washington County and New Brunswick, the bill offers an opportunity to monitor the situation and to ensure that there are not negative consequences before allowing the fish to move farther upstream.

Alewives, a type of herring that divide their lives between salt and freshwater and are a different species from landlocked alewives that have caused problems elsewhere, used to number in the millions in the St. Croix. Due to concerns raised by fishing guides that the fish were responsible for a decline in the smallmouth bass population in Spednic Lake, lawmakers ordered fishways on the St. Croix closed in 1995. Since then, the number of alewives in the river plummeted to 1,300 last year. An attempt to reopen the fishways in 2001 failed, despite protests from the Canadian government that the closure violated international agreements.

Alewives, which spend only about two months in the river, are an important food source for other fish and wildlife in the St. Croix. One biologist believes low numbers of young eagles in the area may be attributable to the decline in alewives. Having more alewives in the river could also help Atlantic salmon, which are endangered although not in the St. Croix, because the alewives divert predators away from the young salmon leaving the river.

In the ocean, alewives are eaten by cod, pollock, haddock and other marine groundfish. Although there have been increasing restrictions on groundfishing, the populations of some species have yet to recover and some believe that having too little food available could be part of the problem.

Alewives are also an important – and cheaper – source of bait for Maine’s lobstermen.

On the other side of the equation, there is little evidence that alewives have hurt the region’s bass population. In fact, some studies show that where alewives and other fish live together, the lakes have larger, healthier populations of the other fish. Further, it appears that taking water from Spednic Lake was responsible for the drop in the bass population there.

LD 1957 would reopen fishways at only two dams, allowing alewives back into a quarter of the St. Croix River watershed. The fish would still be blocked from Spednic and West Grand lakes. Reopening the fishways and monitoring the status of alewives, bass and other fish and wildlife offers a chance to begin to rebuild a river and marine ecosystem.