FREEPORT, Maine — Following a recent Town Council appropriation, the town’s shellfish community has started what is being called a “historic” effort to address the rapid disappearance of soft-shell clams.
The effort is the first comprehensive, large-scale research project in Maine to study the most significant factors believed to be contributing to the decline of shellfish resources, said Brian Beal, a professor at the University of Maine at Machias and one of the scientists working on the project.
“To the best of my knowledge, I am not aware of any community that has raised this much money for a shellfish research project, ever,” he said. “(It) underscores the commitment by the town to this very important commercial resource that they co-manage with the state of Maine.”
One of the main focuses of the study, along with ocean acidification, is to determine what the impact is of the clam predator and invasive species known as the green crab. The crabs eat spat, which are clams in early larval stage.
Clammers, who have been anecdotally documenting green crabs devouring the clam populations for the last few years, are now getting a chance to put defensive measures in place with this project. They also hope to get some reassurance from the scientific data that the defensive measures work.
In the past, green crabs have been reduced by extended cold periods. But now a warming climate has led to unprecedented increases in water temperatures, allowing the invasive species to prosper and grow without barriers.
Crab traps are being strategically set in the Harraseeket River to catch the crabs. There are also plans to run 18-inch tall fencing, pounded into the mud, blocking off specific coves to set up control areas.
The fencing portion is on hold pending a permit from the U.S. Army Corps of Engineers, which is expected soon.
The fencing is intended to keep crabs from getting into the productive clam flat areas and eating all the spat before it can settle, clammer Clint Goodenow said.
“We’re hoping that if we put a fence across and have the traps out, we’ll slow down some green crabs so the spat settle in and maybe survive,” he said.
To allow for fish passage, the fencing will have sections with gaps, although a pit trap will be placed in each of those areas to help prevent crabs from sneaking into the sectioned-off areas.
The state has previously conducted green crab fencing programs, but never on this large a scale, Beal said. And with state budget cuts, funding for the program is no longer available.
Instead, the town is footing the bill. The Town Council approved an up to $67,000 appropriation in the fiscal 2014 budget, and an initial $35,000 spending for the project in the next budget.
Goodenow said while they have not received the permit for fencing, clammers and other fishermen have been rigging traps to prepare for the project.
They plan to deploy about 100 traps and will fish most of them in coordination with the research project. Others will be aimed at attempting to remove as many crabs from the flats as possible, Goodenow said.
On Friday, he said, a group walked along one of the clam flat coves and lifted up the sod on the banks of the river, revealing hundreds of scurrying crabs.
“It was almost like a horror movie when we moved the sod, there were hundreds of them crawling around so fast,” Goodenow said.
The lower tidal areas of the Harraseeket River are traditionally where clammers have harvested. But in recent years, the clams in those areas have all but disappeared, forcing them to move to previously unharvested upper intertidal areas.
Goodenow said he and other clammers hope the defensive measures prove successful and that they’ll be able to determine better and more effective methods to keep green crabs out of the flats once the research is complete.
“At this point we don’t see any other options,” he said. “If we can’t do something to protect the spat … I don’t what we’ll do. It seems all doom and gloom unless this works.”
He said the crabs are not going to go away, but he hopes this project will help keep the populations low enough in the still remaining productive flats to allow enough clams to survive.
“I hope we can say look ‘we can protect this cove enough and still make a living,’” Goodenow said.
The project will also attempt to measure the effects of other clam culprits, notably ocean acidification, which can lead to acidity levels that dissolve clams.
Toward that effort, another piece of the study will be conducted by Darcie Couture, lead scientist and principal at Brunswick-based Resource Access International.
Couture’s work costs $40,000, with the cost shared equally by the state and town.
The study will work in coordination with the trapping and fencing, but will also try to determine the effectiveness of ocean acidification mitigation practices by testing methods like turning over sections of mud to see if it improves quality of sediment. In addition, researchers will spread pulverized clam shells along the shore, which has been shown to reduce acidity and provide refuge for young clams, Couture said.
At the end of the season, Couture said they will layout plans to launch what their research reveals would be the best strategies for mitigation.
She said the project could serve as a model for other towns seeing similar problems with their clam flats.
“This project has the potential to have a big impact on the entire region,” Couture said. “The results we get from the study will weed out what doesn’t work, so other towns don’t have to waste time on things that don’t look promising.”
She said this is really the first concentrated scientific effort to corroborate anecdotes from people working in the industry.
After months of discussion with the council about getting funding for the project, the fencing permit is now the final remaining hurdle.
“We’re literally waiting and ready to go,” Couture said. “We’ve got the gear ready, the staff is ready. We’re ready to go jump in.”