TURNERS FALLS — Toting buckets and nets, roughly 30 volunteers made the trek down into the muddy pit that is the drained power canal to rescue sea lampreys on Monday.

This yearly rescue, conducted when the power canal is drained for yearly maintenance, is a collaboration between the Connecticut River Conservancy, FirstLight Hydro Generating Co. and United States Geological Survey’s (USGS) S.O. Conte Research Laboratory. Volunteers spent the day collecting the larval and juvenile sea lampreys (petromyzon marinus) from small pools that formed in the bottom of the canal.

These migrating vertebrate are important to the ecology of the Connecticut River, and the rescue allows the creatures to be collected and released, with some going to the S.O. Conte Research Laboratory for research.

Nina Gordon-Kirsch, the Massachusetts river steward at the Connecticut River Conservancy, helped coordinate the rescue on Monday. Gordon-Kirsch explained that the sea lampreys migrate from the Connecticut River toward the Atlantic Ocean, where they collect important nutrients and transport those nutrients through the waterways as they migrate.

“They’re native to this area and they migrate out to the ocean and back up here,” Gordon-Kirsch said. “Because they’re a migratory fish, they’re actually important for the ecological system, because they’re bringing nutrients back and forth.”

According to the Connecticut River Conservancy’s website on migratory fish, sea lampreys only contain cartilage. The creatures have no jaws — only a flat, sucking face. Sea lampreys are some of the oldest species of fish, beating out sharks and sturgeon in available fossil records. The U.S. Fish and Wildlife Service dates the sea lamprey at 340 million years, meaning the species existed in the Paleozoic Era and survived mass extinction.

Although the species is millions of years old, the sea lampreys rescued from the Turners Falls power canal are in the larval or juvenile phase, meaning they are still occupying the fresh water of the power canal for three to five years before migrating to the ocean as they mature.

While FirstLight conducts maintenance within its canal, the young sea lampreys are at risk of dying from the lack of water. Gordon-Kirsch said the sea lampreys can’t survive without water, so a rescue is important to save the species.

“There’s a ton of ecological life that’s in there, so that’s why we’re here today — to help that ecological life stay alive,” Gordon-Kirsch said.

In 2023, the rescue saw roughly 50 volunteers come through to collect the sea lampreys. Due to new safety restrictions and volunteer space, a smaller cohort was assembled this year. The volunteers were expected to canvas as much of the drained power canal as possible.

Diana Chaplin, communications director at Connecticut River Conservancy, said not only do the volunteers provide an important service by preserving the sea lamprey population, but the rescue is also an educational opportunity whereby community members can interact with the environment around them.

“The coolest part about it is being hands-on with this community science activity,” Chaplin said. “You’re learning about sea lamprey while you are actually touching them and holding them while they’re wiggling around. … You’re actually having a really positive impact by saving them.”

Among the volunteers who were embracing this educational opportunity on Monday was Rachel Keeffe, who is teaching vertebrate anatomy at Mount Holyoke College. She participated in the sea lamprey rescue in 2023, and spoke to her students about the species. She pointed out how important the sea lampreys are when it comes to understanding how vertebrates develop, especially as sea lampreys are one of the oldest vertebrates living today.

“I love to be able to come back and tell my students, ‘These guys are in our river,’” Keeffe said.

Erin-Leigh Hoffman can be reached at ehoffman@recorder.com or 413-930-4231.