Thirteen feet below the surface of Woods Hole harbor, a lobster shelters under a plastic shield in a wire cage. An experiment is happening: every seven seconds on the dock above, a pile driver pounds a long, steel post deeper into the muddy harbor bottom nearby.
Each strike creates an underwater boom.
Above the water, the noise is even more piercing. Andria Salas, a marine biologist from the Woods Hole Oceanographic Institution (WHOI), spends the day with ear protection always at the ready.
Part of her job is to handle the 50-odd lobsters involved in the experiment. She's collecting data about the animals' heart rates and movements every time the pile driver strikes.
To do that, she must outfit each lobster with a specialized tag.
鈥淚t鈥檚 a lobster saddle,鈥� she says, demonstrating how the tags are strapped around a lobster鈥檚 middle.
Salas says she woke up with the idea for the wearable tags. Each one is made using a snorkel mouthpiece, custom circuit board, and Velcro belt.
鈥淚t鈥檚 worked pretty well," Salas says. "We鈥檝e never had one fall off.鈥�
Aran Mooney, the lead scientist on the project, puts it this way: 鈥淭hey're basically Fitbits for lobster.鈥�
The experiment happening here at this dock is designed to replicate, at small scale, the pile driving necessary to construct an farm.
The goal is to understand how a variety of marine creatures 鈥� not only lobsters, but other fish-market-friendly species like scallops, flounder, black sea bass, and squid 鈥� respond to the noisy, intensive work of building an offshore wind farm.
It鈥檚 something fishers and regulators are especially interested in.
鈥淣o one's analyzed lobster heart rate data in respect to sound exposure or these stress responses,鈥� Mooney says. 鈥淪o this is kind of completely new.鈥�
More research needed as offshore wind industry faces challenges
The steel pole Mooney鈥檚 team uses is only one foot in diameter, compared to massive 30-foot-wide piles used by offshore wind developers. But the data the team is gathering can be scaled up, Mooney said.
鈥淏eing 5 or 10 meters away from our piling here is the equivalent to being about 200 or 300 meters away from an offshore wind farm [under construction, as far as] the sound levels that you would receive,鈥� Mooney said.
This experiment is funded by the federal Bureau of Ocean Energy Management. It comes at a time when the offshore wind industry faces numerous challenges, including rising costs and a skeptical president-elect. At a , Donald Trump vowed to end offshore wind on 鈥渄ay one鈥� of his second term.
For his part, Mooney said he鈥檚 not working for 鈥� or against 鈥� offshore wind. He鈥檚 a scientist studying animals; for him it鈥檚 all about tracking heart rates and signs of stress.
鈥淲e don't know if these lobsters are responding to sound,鈥� he said. 鈥淲e don't know if that response is negative. It could be positive. Or it could be no response at all.鈥�
Underwater species show mixed response to pile-driving noise
Already, the WHOI team鈥檚 earlier studies have shown that squid, which detect sound through vibration, responded dramatically to pile-driving noise 鈥� at least, at first.
鈥淭hey ink, they jet," Mooney said. "They color-change and respond to this noise. But they habituate quickly. They're not getting deafened, and they kind of go back to their normal behavior of feeding and trying to mate really quickly. So with that data, you can kind of say, 鈥極kay, I think the squid fishery is probably going to be okay.鈥欌��
But it鈥檚 a different story for scallops, one of the highest value fisheries in the U.S. As soon as scallops were exposed to pile driving noise, they clammed up.
鈥淸With] every strike, they close a little, and then they try and open, and they close a little, and then try and open. And they don鈥檛 habituate to that sound,鈥� Mooney said. 鈥淭hat's very, very exhausting for the scallop.鈥�
As far as lobsters go, Salas said they may find that the noise is making the crustaceans鈥� hearts skip a beat.
鈥淲e're looking at things called cardiac pauses that crustaceans can have," she said. "They can do that when they sense something in their environment is startling or a stressor.鈥�
Earplugs for lobsters? Scientists look for sound mitigation ideas
Offshore wind developers are already aware of problems that construction noise may create for marine life. To 鈥� walls of air bubbles, released from the ocean bottom. It鈥檚 a good start, Mooney said, but not targeted for the entire ecosystem.
鈥淎 lot of the mitigation measures are not designed for animals on the bottom, the fishery species that are detecting the vibratory component of sound,鈥� he said. 鈥淭hat's really just so fundamentally different.鈥�
The WHOI team ultimately hopes to identify best practices to make construction noise less harmful to the bottom-dwellers. For instance, they鈥檙e looking at how lobsters respond when the pile driving is ramped up slowly.
Analyzing the data they collected will take about a year. The researchers hope to be back here in Woods Hole Harbor, running more experiments 鈥� and wearing ear protection 鈥� next fall.
