Maquoit Bay is seen in Brunswick in May. Portland Press Herald file photo by Derek Davis

BRUNSWICK — As water temperatures rise and invasive species, such as the predatory green crab, continue to thrive in Maine waters, communities including Brunswick and Harpswell are turning to quahogs to help bolster the local fishing economy and improve the ocean ecosystems.

Brunswick and Harpswell received grants for $19,000 and $15,000, respectively, from the Maine Shellfish Restoration and Resilience Project through the University of Maine. The project seeks to help “restore shellfish flats, improve clam flat or mussel bed productivity, find and fix pollution (and) work with town and state officials to open closed flats,” among other goals, according to the project description. 

Roughly 6 or 7 mm quahog seeds. These baby hard shell clams need to reach at least 10 mm before they will be big enough to be planted in the mudflats in Brunswick, as part of a $19,000 shellfish resilience grant. Hannah LaClaire / The Times Record

In Brunswick, the funding will be used to help strengthen the town’s wild quahog — or hard-shell clam — fishery.

The town will purchase 500,000 1 mm quahog “seeds,” (or as many as 1.5 million if approved for another grant from Bowdoin College) and grow the animals in floating mesh bags until they reach 10 mm, at which point they will be big enough to be planted in Maquoit Bay, Middle Bay and the New Meadows River, where they will hopefully grow over the next 3 1/2 years and then be harvested. Local farmers and harvesters will help monitor and care for the quahogs as they grow.

“With the use of standard and simplistic shellfish farming nursery techniques, we will combine both the local knowledge of generation shellfishermen and shellfish farmers to help bolster the existing natural population of quahogs,” Dan Deveraux, Coastal Resources Manager wrote in the grant application. 

Shellfish harvesters have been digging clams, quahogs and mussels in Maquoit Bay for more than a century. Between the 1940s and 1960s, the area was a “prolific quahogging area,” Devereaux told The Times Record last year, and even more so after a warm spell in the 1950s caused the population to explode. 

But strain on the mudflats and over-harvesting caused the population to decline, hastened by a 1988 algal bloom in Maquoit Bay that killed everything in the water. 

Devereaux and other town officials have since worked to replenish them throughout the area. 

Since 2012, the Marine Resources Committee has conducted quahog “relaying and planting” projects, in which young and adult quahogs are taken from higher density areas like New Meadows, Maquoit and Middle Bay and moved them to areas without a commercial population of soft-shell clams or quahogs like Bunganuc, Harpswell Cove and Thomas Point Beach.

Clammers were once resistant to quahogging, Devereaux said previously, but as soft-shell clams have declined in the face of climate change and green crabs, which decimated the population between 2012 and 2015, many have come around to the lucrative per-piece market. 

In the last five years, officials have seen a resurgence of hard shell clams — the waters are warmer for them, they’re larger, heavier and header, making them more resistant to predation. 

In 2013, there were 98,975 live pounds of quahogs harvested in Brunswick, valued at $101,044. Three years later there were 389,335 pounds with a value of $637,437. By 2018, there were 767,035 live pounds of quahogs harvested in Brunswick with a total value of $1.35 million. Data from 2019 is not yet available. 

Comparatively, in 2012 there were 660,201 live pounds of soft-shell clams harvested in Brunswick, valued at just over $1 million. By 2015, those numbers had dropped to 96,809 pounds, valued at $540,000. 

The species is recovering, back up to 524,127 pounds and $1.02 million for 2018, but “nothing that is comparable to the 1990s, where at the time Brunswick was landing close to a million pounds,” Devereaux said. 

Even though quahog harvests continue to surpass soft-shell clams (by weight), town officials are still concerned with making sure the species not only survives, but thrives, not only for economic purposes, but also for environmental ones. As bivalves, clams provide important water filtration for the ocean. Coastal development is creating more nutrient runoff, Devereaux said, and without more, “it’s a recipe for disaster.”

A quahog relay project in 2015, in which town officials transplanted quahogs from densely populated areas like Maquoit Bay into sparse ones likes Bunganuc and Thomas Point Beach.

“Keep shellfish in the bay and you have a better chance to survive, he said. 

Last spring, town clam seed inventories showed a decline in the natural seed settling out on the flats, something officials credit to predation and coastal and ocean acidification. This “will most certainly lead to a decline in resources, ultimately leading to a curtailment of commercial licenses or the implementation of catch quotas, or both,” according to the grant application. 

Brunswick has 62 licensed harvesters, and “we’re trying to keep there guys on the mudflats,” Devereaux said.
A smaller-scale project this summer, during which Devereaux grew about 1,000 1 mm quahogs in floating bags, was successful. 

He hopes this larger endeavor will help further mesh farming and wild shellfisheries. Even if it doesn’t work, “we can at least try,” he said. 

In Harpswell, the thought behind the project is much the same. 

The commercial harvest of soft-shell clams and quahogs supports 73 licensed harvesters in town, “and has provided a livelihood for several generations of clamming families,” Marine Resources Coordinator Paul Plummer wrote in the grant application.

But just like in Brunswick, soft-shell clams are struggling to fight against predation and climate change. 

“Rather than sit by and passively watch the decline of their fishery, the Harpswell Marine Resources Committee is seeking out new ways to enhance and sustain their important shellfish resources,” Plummer wrote. 

In 2016, Harpswell soft-shell clam landings show there were 97,940 live pounds harvested, valued at $283,763. By 2018, the numbers only slightly increased, to 128,220 pounds and $252,976.

Comparatively, In 2016, Harpswell quahog landings show there were 112,379 live pounds harvested, valued at around $173,000. Two years later, that more than doubled, with 244,000 harvested with a value of almost $390,000. The numbers for 2019 have not been released yet. 

With its funding, Harpswell plans to build a tidal upweller, a dock-like structure with decking that comes up to reveal little silos below, Plummer explained. The silos will be filled with about 500,000 very small quahogs, and as the tide comes and goes, the shellfish are fed. This puts them in an environment where they are constantly eating, hopefully growing faster, and are kept safe from predators. In October, the bigger quahogs will be planted in the town mudflats. 

“If quahogs are making a comeback, we’re going to focus on them,” he said in an interview.

Both towns will get their quahog seed from Muscongus Bay Aquaculture based in Bremen. 

“As communities struggle with strategies to move forward in the face of a rapidly changing environment, we feel that it is important to determine if a method is successful or not, and use those lessons to plan next steps,” he said in the grant application. 

Both towns hope to share their findings with other communities to learn what works and what does not. 

“We can share with municipalities and help bolster their hard shell clam stock if they have it,” Devereaux said, “and if they don’t, who knows, maybe in 10 years they will.”