July 31, 2012 — It’s time alewives were allowed into the upper reaches of the St. Croix River. Research, in addition to dozens of ponds and streams in Maine, show that alewives can coexist with smallmouth bass. Until there is solid scientific evidence that bass populations will diminish with an influx of alewives north of the Grand Falls Dam in Washington County, holding them back from their natural spawning ground will only harm the greater habitat.
The matter has been a contentious one since the 1980s when alewives were blamed for the decline of the smallmouth bass population in the St. Croix, threatening the livelihoods of local bass fishing guides.
Prior to 1980 there was an inefficient fish passage at Milltown Dam on the St. Croix that allowed only a small number of alewives to pass through, according to a 2007 report completed by Lewis Flagg for the Atlantic Salmon Commission. A new fishway was constructed in 1980, and alewives swam north. By the mid- to late-1980s, smallmouth bass — a non-native fish introduced by sportsmen — had substantially declined.
So the Maine Department of Inland Fisheries and Wildlife and the New Brunswick Department of Natural Resources completed a 10-year study of Spednic Lake, a part of the river. The study concluded: A lake drawdown of nine to 14 feet made the young bass’ protective rock habitat disappear, and they were forced to compete for food and habitat with young perch and alewives.
It was not the alewives that caused the bass decline but the loss of protective habitat.
Still, the St. Croix River Steering committee agreed to close the Vanceboro fishway during the alewife run. And in 1995 the Maine Legislature passed a bill that closed the Woodland and Grand Falls fishways. Bass rebounded, but the move resulted in a dangerous drop in the number of alewives, from 2.6 million in 1987 to 900 fish in 2002. The law was amended in 2008 to unblock the fishway at Woodland, but the fish are still prevented from reaching 98 percent of their traditional spawning ground.
Read the Full article at the Bangor Daily News.