It’s a dirty job, but digging for blood and sand worms along the Maine coast can pay well, particularly in areas of the state where it can be hard to make a living. Maine’s annual harvest of these popular bait worms, however, continues to decline, posing a quandary for marine biologists who cite climate change and predation as possible factors.

Wormers, as they’re called, would like to work with marine biologists to ensure a healthy and robust industry.

As he walks across the mud flats off Beals Island, worm digger Donnie Bayrd feels the suction of silt pull at his boots. He twists each foot slightly from side to side to prevent the mud from closing in around his boot — an occupational hazard that has brought down more than one wormer into the muddy flats.

Bayrd says it’s worth the trouble to brave the fragrant and unforgiving mud flats of Washington County in search of these creatures, which can also bite. Sport fishermen, he says, pay to have the worms flown around the world and have been known to try and make them last.

“They cut these up in pieces and fish with them. The bigger the worm, the better they like it because they can get a half-dozen pieces out of them,” he says.

Landings for sand and bloodworms peaked in the early ’70s, when combined harvests were closing in on 2 million pounds and valued at over $1 million. In 2014, the combined value had grown to over $7.5 million, but the harvest had diminished to under 700,000 pounds. Marine biologists are challenged by the drop in worm landings.

“Since 2002, there’s been a 50 percent decline in sand worms, a 42 percent decline in bloodworms,” says Brian Beal, professor of marine ecology at the University of Maine at Machias whose research focuses on shellfish and clams in particular.

Beal says it’s possible the invasive green crab, which has a voracious an appetite for clams, could be at least partially responsible for the decline in the sea worms harvest.

“We know that things like green crabs do prey on clams and they also prey on worms,” he says. “Studies that were done in the 1950s and ’60s, and some of the work that we’ve done in Freeport looking at the gut contents of green crabs, show us pieces of worms in their guts, so we know that they’re are eating these worms, as well as clams.”

Washington County worm diggers have their own theories.

“You have biologists that come around, and I’m not taking away from people who go to school, but very few of them say, ‘Well, what do you guys think?’” says Fred Johnson of Steuben, president of the Down East chapter of the Independent Maine Marine Worm Harvesters Association.

“They don’t see the changes in that inner benthic zone that we’ve seen over the years,” Bayrd says.

In Milbridge, Bayrd runs the Striper Bait Co. and employs dozens of diggers. He’s a big believer in modern science, but says he’d like to see some of the $43 the state collects from nearly 850 wormers statewide dedicated to research that could be conducted alongside those who hit the flats daily.

Bayrd says scientists have yet to observe the changes in the industry that he has witnessed for more than 50 years.

“Everything changes, the worms move out of the rivers in a wet year or rainy year and the line of worms will be further down the river towards the salty water, and in a very dry years they’ll come into the inner rivers. So it’s very dynamic. It’s subject to change. That’s the only constant in the universe and it is with worms as well,” he says.

Bayrd says the lower numbers of worms taken each year has a lot more to do with the fact that fewer and fewer Mainers are inclined to engage in a back-breaking occupation, and he believes that the worm populations tend to rise and fall in cycles, a position not shared by scientists such as Beal.

“If clams and worms were cyclical, then you ought to be able to predict with fairly good certainty what the population is going to be in a few years, and no one can do that,” he says.

Earlier this year, the worming industry was alarmed by a bill proposed by Rep. Robert Alley, a Beals Democrat, who had hoped to learn more about worming by closing the industry down between Dec. 1 and March 31. Alley’s bill will come up Monday before the Legislature’s Marine Resources Committee, but wormers who sell to European buyers during those months raised a ruckus.

Alley says he will amend his well-intentioned study bill to leave the state open to worming year-round.

This article appears through a media partnership with Maine Public.