HARPSWELL — The state of the Harpswell clam industry is not very strong, but it may be getting stronger.
At a Jan. 26 meeting, the town’s Marine Resources Committee reviewed a draft report on its activities over the past year to send to Town Meeting in March.
“The Marine Resources Committee continues to search for ways to slow or reverse the dramatic decline in the town’s soft-shell clam populations,” the report states.
Committee members point to various reasons for the decline, including predation by invasive green crabs, ocean acidification, a shellfish disease called neoplasia, and competition with blood worm harvesters.
Nevertheless, members report that harvesters have seen signs of increased natural reproduction in the town’s clam flats. At the same time, the actual number of mature clams that can be harvested remains low.
“This is the worst yet, this past year,” Committee Chairman David Wilson said.
One strategy the committee has employed to fight the decline is placing nets over areas with significant juvenile clam populations.
Nets have been used in areas like Georgetown to keep green crabs out of the clam stock. They also keep worm harvesters out of the mud directly below the nets, the report notes.
The nets, however, are not a catch-all solution. They do not keep out milky ribbon worms, which prey on young soft-shell clams, and whose numbers seem to be increasing.
“The ribbon worms are the worst we have seen yet,” Wilson said.
The nets are currently placed in Henry Creek, Spruce Cove, Big Oak Ledge, Little Oak Ledge and High Head.
In terms of combating neoplasia, a disease often described as “clam leukemia,” the committee earlier last summer sent tissue samples to a lab in Pennsylvania to find out which coves had the highest levels of infected clams.
The results were “mixed,” according to Darcie Couture, the town’s marine resources coordinator. While the clam samples from coves had evidence of the disease, she said, “other areas were clear.”
“That means they’re good candidates for future re-seeding,” she added.
Committee members are weighing the option of joining a grant sought by the Manomet Foundation, which would allow multiple towns in Maine to pool resources to explore aquaculture methods for growing clams in municipal waters.
Perhaps most significantly for local harvesters, in the past year the committee has worked closely with the state Department of Marine Resources to re-open many areas in town that had for years been closed to harvesting.
The committee got results this summer, when the DMR opened up more than 1,500 acres of intertidal flats and tidal waters that had been closed because of pollution or expired state surveys.
“This is one of the largest chunks of area we’ve gotten back in at least a decade,” Couture said Wednesday.
Those areas are now open in a mixture of seasonal and year-round harvesting.
But the future of the harvesting may not even lie with soft-shell clams.
Clam diggers have noticed more and more quahogs, or hard-shell clams, in the town’s flats. Perhaps due to warming water temperatures, or for “whatever reason,” Couture said in an interview in December, “(quahogs) seem to be more prolific.”
The marine resources committee has discussed seeding juvenile quahogs in the town flats to bolster the population.
“That really tells you there’s something going on in this area,” Couture said last month. “They would not even be talking about quahogs … except that soft-shell clams are so affected by all of these forces that these communities are trying to find ways to adapt and continue to make their living on the waterfront.”
Quahogs dug out of Maquoit Bay in Brunswick in 2014.