🔒Inside the Notebook: Seeding clams in Downeast Maine

When I interviewed Tim Sheehan last fall in Pembroke for our Oct. 19 story “Company seeks to build up clamming in Maine's poorest county,” I was impressed by the many creative ways he and his wife, Amy, have been bringing innovation to a tradition-bound industry. So I wasn't surprised by the recent email I received from Tim telling me about a clam-seeding initiative he and some local clammers undertook in mid-April.

“The mudflats were just starting to flood,” says Sheehan, telling me in a follow-up phone interview how eight clammers set out in two skiffs with 350,000 baby clams to broadcast onto the soft mud in synch with the advancing tide. He figures the young clams had close to 20 hours of protection from seagulls — sufficient time to burrow deep enough into the mudflats by the next afternoon's low tide to escape predation. The early spring seeding also was timed to minimize predation from green crabs that are still in the deeper waters where they over-winter.

The seeding project is a collective effort by the 250 local diggers who sell clams to the Sheehans' Gulf of Maine seafood business, which diverted $1 for every bushel of clams it purchased into a fund for buying baby seed clams from the Downeast Institute in Beals. The diggers selected two areas they thought held the greatest promise for rebuilding the clam populations: Hersey Cove in Pembroke and East Bay in Perry. More seeding is planned later this spring, paid for by local diggers and Gulf of Maine.

“This is a starting point, a chance to gather 'round the idea that seeding might work,” he says. “These clams are going to take three to four years to mature. Let's see what happens.”

“I really hope they see a return,” says Kyle Pepperman, a 2009 graduate of the University of Maine at Machias with a degree in marine biology who works as an aquaculture production and research assistant at the nonprofit Downeast Institute.

Investing in the future

In the warmer waters of southern Maine, he says, the seed clams will reach the two-inch harvestable size in about a year. Although the three-to-four-times slower rate of growth in Cobscook Bay increases the likelihood of predation from green crabs, gulls, moon snails and the effects of digging before they reach harvestable size, Pepperman says the young clams will reach sexual maturity within a year. So, even if most of the 350,000 seed clams sown in Pembroke and Perry don't reach harvestable size, he says there's a good chance some of their offspring will end up in someone's chowder.

“One clam can produce 20 million offspring,” he says. “An investment in seed clams is an investment in the future of the industry.”

Pepperman says he would have liked to have seen the Pembroke and Perry clammers take it one step further by placing protective netting over the seeded flats for a year to keep out predators until the young clams are large enough to burrow to “refuge depth” in the mudflats. “With netting, we've seen 60% survive,” he says.

'Tragedy of the commons'

The rub, of course, is that the netting keeps clammers from digging in those flats for up to a year — a potential loss of income if other flats aren't available, or rich enough, for harvesting comparable quantities of clams.

Such is the “tragedy of the commons,” an economic theory that says shared resources such as clam flats inevitably put individual self-interest in conflict with the common good of all users, potentially depleting that resource unless everyone agrees voluntarily to some limits. It's a conundrum that Maine's lobster industry seems to have reasonably solved with self-imposed limits such as notching the tails of egg-bearing females before tossing them back into the ocean where they'll continue spawning.

Can the clamming industry do the same?

With Maine's softshell clam industry retaining its second place standing in overall value at $22.5 million in 2015, a record for the fishery, despite a 1 million pound drop in landings, the small step of seeding mudflats just taken in Cobscook Bay (and already being done elsewhere) is an important one.

Read more

Seafood retailer setting up shop in Bangor

Gulf of Maine mussel population drastically dropping

Downeast economy already reeling from clam flat closures

Select mud flats reopen for shellfish harvesting