AUNE Professor’s Work Helps Recover Dwindling Alewives and Smelt
The residents of Maine’s North Haven island will be waiting anxiously next spring to see if the smelt return from the sea. If some of the small fish come back, to where they were released as hatchlings, it will be the first time they will have been seen on North Haven since 1978. And it will be one victory in a much larger effort to restore near-shore populations of the smelt and alewife, led by Charles Curtin, former faculty in AUNE’s Department of Environmental Studies and himself a North Haven resident.
The work is important, for these fish represent the bottom of the food chain, so restoring them is less about the fish and more about restoring the entire ecosystem and rebuilding what was once one of the world’s richest marine habitats. The alewives have been gone for century and smelt have been gone in living memory, Curtin said. Both are sea-run fish, which return from the ocean to inland waterways to spawn. But their numbers have declined dramatically. The alewife is used for lobster bait and for human food and is also an important food source for fish-eating birds. Once so thick in Massachusetts Bay that a river tributary was named for it, the alewife is now endangered, and extinct in every state but Maine.
Smelt, too, are dwindling. In 2004, the National Oceanic and Atmospheric Administration listed it as a Species of Concern because its numbers have dropped so precipitously, probably because of fishing pressure. Unlike the alewife, the smelt doesn’t lend itself to a large fishing industry, but it is very important to Maine communities where people have been smelting for hundreds of years.
A Community Effort
The whole North Haven community, fewer than 400 year-round residents, is very much a part of the restoration project. Everyone is invited to have input, and an oversight board comprising residents, fishermen, and others with a stake in its outcome manages the alewife restoration.
Students at the North Haven Community School have been raising smelt in a laboratory at the school for the last two years, using a technique developed at the University of Massachusetts. They capture smelt in the wild, then extract eggs and sperm, and raise the hatchlings for ten days before releasing them. Smelt go up brackish streams to ponds to spawn and the young return the next year, so it’s better to rear smelt in a laboratory, at the school, and then release them as soon as they are big enough, Curtin said.
But it’s the alewife population that, if restored, will be the real triumph and an economic boon to the economies of Maine islands. Alewives, Curtin said, could bring in as much as $15,000 each year to North Haven, money that will be used for more restoration efforts. It’s important for such a project to be able to stand on its own financially, he said. Traditionally, funding for conservation projects continues for three to five years, yet scientists learn very little until at least 10 years into a project.
Curtin and his colleagues, including former AUNE student Charles Soucy, MS ’12, first reintroduced the alewives to North Haven in 2011 and again in 2012. They trucked in the fish from Maine’s Kennebec River to stock Fresh Pond, once a thriving alewife fishery. Unlike smelt, the alewives will only return to the island’s fresh water pond to spawn after four or five years in the sea, so it will be a couple of years before they learn whether the alewives survived the trip down to the sea and then back to Fresh Pond.
Support has been strong for the project. Money has come from the Davis Conservation Foundation; the Maine Outdoor Heritage Fund, supported by the Maine State Lottery fund; the Maine Community Foundation/Broad Reach Fund, and a Maine Sea Grant.
How will Curtin know if the projects are successful? If the stocks of smelt and alewife return to North Haven, and if the off-shore ecosystem is improved by such things as more cod, and in the ponds, more bass and other predators, he said.
The Gulf of Maine, and particularly Penobscot Bay, had the richest marine ecology in the world at one time, a fish and mammal population that is largely lost. We’re working on putting it back.
Read more about the project.