Saving Seafood

Eelgrass decline in Chesapeake Bay to potentially cause shifts in food web, study says

September 19, 2025 — Beneath the surface of the Chesapeake Bay, a quiet but significant transformation is taking place. Eelgrass, long a foundational seagrass species supporting fish, crabs, and other marine life, is declining in parts of the Bay. Its warmer-water relative, widgeon grass, is expanding in its place.

Researchers from William & Mary’s Batten School of Coastal Marine Sciences and the Virginia Institute of Marine Science (VIMS) conducted a study, and say this shift could have major ecological consequences and potentially affect fisheries and the health of the Bay itself.

What’s Happening Underwater

Eelgrass and widgeon grass may look similar at first glance, but their differences are significant. Lauren Alvaro, a marine ecologist who conducted extensive fieldwork for the study, explains: “Not all seagrasses are created equal. Eelgrass has broader leaves like linguine, while widgeon grass is more like angel hair pasta. And those differences affect the types of creatures they support.”

Eelgrass meadows typically support larger animals, such as blue crabs and fish prized by anglers. Widgeon grass, meanwhile, supports smaller animals, and while there may be more individuals per gram of plant material, the overall biomass is lower. In other words, even if the Bay looks full of seagrass, the types and sizes of animals it supports are changing.

Read the full article at 13 News Now

Saving eelgrass, the most important plant you’ve likely never heard of

January 16, 2025 — Matthew Long peers over the side of the research boat Calanus, into the dark water of Hadley Harbor, about 2 miles from Woods Hole.

There’s a meadow down there, according to Long, a marine chemist at the Woods Hole Oceanographic Institution. Acres of a willowy green plant called eelgrass.

Eelgrass is the dominant species of seagrass in New England, but it’s little-known and largely unsung. And no wonder — it’s impossible to see from shore and barely visible from the boat.

But Long assures me it’s there. As his colleagues put on scuba gear to collect samples, he ticks off the reasons why healthy eelgrass meadows are critical for the New England coast.

Read the full article at wbur

Eelgrass and Ocean Acidification: California Takes Action

October 4, 2016 — What do eelgrass, the California state legislature, crabbers, and Ocean Conservancy have in common? They are all part of the solution in California’s remarkable actions this past week to address the threats that ocean acidification presents to California’s healthy fisheries, marine habitat and coastal jobs.

Governor Jerry Brown just signed into law a pair of bills that will address the concerns over ocean acidification raised by oyster growers, crabbers and others who make a living off of the ocean.

The two pieces of state legislation were crafted by Assemblymember Das Williams and Senator Bill Monning, as tailored place-based solutions to what amounts to a global problem. SB 1363 will protect and restore eelgrass habitats, increasing carbon sequestration amongst the roots of this coastal vegetation.

Read the full story at the Ocean Conservancy

GEORGE LAPOINTE and TOM TIETENBERG: Reducing Maine’s carbon footprint

September 8, 2016 — We know the threat of climate disruption to Maine is real in part because we are experiencing early warning signs. The science is also clear that the problems will escalate if we do not act to further reduce carbon pollution.

There are now many important examples of how a warming climate threatens Maine, and here is one that strikes close to home for many Mainers: our changing marine environment could spell serious trouble for commercial fishing and all those who rely on it for a living. Consider the following:

• The Gulf of Maine is warming faster than 99 percent of world’s oceans.

• Maine’s shrimp fishery has been closed for several years now, attributed in part to warmer waters.

• Lobstermen and other fishermen are bringing up in new species from warming waters with their catch — presence of new species is not usually a good sign. For example, warming weather contributes to large increases in green crab populations, which ravages Maine clam flats and eelgrass beds.

• Clams and other shellfish face an existential threat: the same carbon pollution that is warming the globe is making ocean water more acidic and that makes it more and more difficult to build a shell.

These problems affect many Mainers, from commercial fishermen to all the households and businesses that they interact with. Commercial fishing is a $2 billion part of Maine’s economy, employing roughly 39,000 people.

Read the full opinion piece at Central Maine

Invasive species exploit a warming Gulf of Maine, sometimes with destructive results

October 28, 2015 — Until two years ago, if you had walked down to the shore of Maquoit Bay at low tide, you would have seen a meadow of eelgrass stretching nearly as far as the eye could see across the exposed seafloor. Here near the head of the bay, the sea grass stretched for two miles to the opposite shore, creating a vast nursery for the shellfish and forage species of Casco Bay, of which Maquoit is a part.

Now there’s only mud.

Green crabs took over the bay in the late fall of 2012 and the spring and summer of 2013, tearing up the eelgrass in their pursuit of prey and devouring almost every clam and mussel from here to Yarmouth. Fueled by record high water temperatures in 2012 and a mild winter in 2013, the green crab population grew so huge that the mudflats of Casco Bay became cratered with their burrowing, and much of the Maquoit and adjacent Middle Bay bottom turned into a lunar landscape.

Eelgrass coverage in Maquoit Bay fell by 83 percent. With nothing rooted to the bottom, the seawater turned far muddier, making life hard on any plants or baby clams that tried to recolonize the bay.

“We were astounded,” says Hilary Neckles of the U.S. Geological Survey’s Patuxent Wildlife Research Center, who linked the destruction to the green crabs. “The ecological ramifications really reverberate throughout the ecosystem, because sea grass is the preferred habitat of so many fish and shellfish species.”

Over the past decade, the Gulf of Maine has been one of the fastest-warming parts of the world’s oceans, allowing warm-water intruders to gain a toehold and earlier invaders such as the green crab to take over. Coupled with declines of the cold-loving species that have dominated the gulf for thousands of years, the ecological effects of even more gradual long-term warming are expected to be serious, even as precise forecasting remains beyond the state of scientific knowledge.

Scientists say the 2012 “ocean heat wave” was an unusual event, and that the 10-year accelerated warming trend is likely part of an oceanographic cycle and unlikely to continue. But the gulf has been consistently warming for more than 30 years, and long-term forecasts project average sea surface temperatures in our region could reach 2012-like levels by mid-century. The events of 2012 and the nearly as warm year that followed likely provide a preview of things to come, of a gulf radically transformed, with major implications for life on the Maine coast.

Genevieve MacDonald, who fishes for lobster out of Stonington, was standing on the dock at Isle au Haut one morning that summer, looked in the water, and couldn’t believe her eyes. There, swimming around the harbor like mackerel, were dozens and dozens of longfin squid, temperate creatures rarely seen in the chill waters of eastern Maine. “If you had a cast net you could have brought in a whole basket full of squid,” she recalls.

Read the full story at Portland Press Herald