July 14, 2022 — Hutchins, a habitat restoration biologist with National Oceanic and Atmospheric Administration, lives and works on Cape Ann. Along with a small group of volunteers, he monitors the baby eels migrating upstream at Mill Brook between spring and fall. In a year, sometimes they’ll document well over a thousand elvers.
Half a century ago, fishermen harvested millions of pounds of American eels annually up and down the Atlantic Coast. By 2013, however, researchers estimated the population had dropped by half.
Experts suspect overfishing and coastal development have played a role in the decline, along with eutrophication — when nutrients from sewage and fertilizers choke the oxygen from ponds and streams.
Another fish fundamental to fresh and saltwater ecology is the river herring.
Alewives and bluebacks are migratory herring that range along the East Coast from Florida to Maine. Whereas eels are born in the ocean but live in freshwater, river herring live in coastal waters and only venture inland to spawn.
As with eel, river herring populations began to crash in the 1980s, coinciding with advances in commercial fishing techniques and new construction along the coast.
Massachusetts is home to about 3,000 dams, with many built in the 19th century for water power, reservoirs, or flood control.
“A dam in a river is like a blocked artery; it’s like a heart attack,” said Robert Kearns, a climate resiliency specialist at the Charles River Watershed Association. “It degrades the water quality behind it; reduces the dissolved oxygen which fish rely on to breathe and to live … and creates a habitat that’s better for invasive species.”
Beyond commercial fishing, a report by the American Sportfishing Association found saltwater sport fishing generates over $500 million dollars a year in sales, wages, and taxes in Massachusetts.
But amid the reality of human-made climate change, the future of the herring and the eels, on which so much depends, remains very much in question.