Blue crabs. Photo via Benjamin Wilson, Flickr
Blue crabs. Photo via Benjamin Wilson, Flickr

Crab Chowder?

In 2012, northeast sea surface temperatures reached an all-time high. Many speculate that rising water temperatures have contributed to a record high catch of 126 million pounds of American lobster, Homerus americanus, in the Gulf of Maine. However, the steady rise in New England’s sea surface temperatures may have also made southern areas of New England inhospitable for lobster. In a recent interview with AccuWeater, Maine Lobstermen Association’s Patrice McCarron said, “In southern New England, Buzzard Bay, Mass., and the waters off of Rhode Island, temperatures in the Long Island Sound area have become too warm for lobsters.” Lobster catch in these areas has plummeted since the 1990s.

The warming trend in New England waters has caused alarm for local fishermen, and we’re only beginning to understand the ways climate change might affect our fisheries. While some treasured New England species may relocate father north, it’s possible that other species will move into this region and create new economic opportunities.

We’ve written before about some of these species moving north as water temperatures rise, and now we can add another to the roster—blue crabs. Although blue crabs are traditionally caught off Maryland and Virginia, fishermen in Long Island Sound have been seeing more of them lately. Some think that, in time, Long Island Sound could replicate the blue crab fishery of southern areas like Chesapeake Bay.

The blue crab, Callinectes sapidus, whose Latin name can be translated to mean “beautiful savory swimmer,” is the Maryland state crustacean and the most valuable shellfish in the mid-Atlantic region. The crabs can grow to be around 4 in long and 9 in wide, weighing around 1 pound, and reaching maturity in 12 to 18 months. The bottom-dwelling blue crab can live in a range of salinities, feeding off of crabs, claims, snails, eelgrass, sea lettuce and decayed vegetation. Blue crabs can be found all along the Atlantic Coast, with a prominent population in Chesapeake Bay presently suffering from habitat degradation and overfishing.

Could Maryland’s pride species create a new industry in New England Waters? The blue crab, caught for sale in both hard and soft shell forms, is currently sold at a market price in Maryland of $39.25 per dozen. With the growing blue crab population and a high demand market, does New England clam chowder have a new competitor on the way?

Scientists are careful to note that the long-term effects of climate change on species like blue crabs are still far too uncertain to predict the future of a fishery, but one thing is for sure—New England’s ocean is changing, and marine life is on the move.

An Atlantic sturgeon. Photo credit: NOAA/Robert Michelson
An Atlantic sturgeon. Photo credit: NOAA/Robert Michelson
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New England’s Endangered Living Fossils

Categories: Creature Features

Tomorrow, the US will observe Endangered Species Day, an opportunity to “recognize
the national conservation effort to protect our nation’s endangered species and their habitats.”

If you’re a regular New England Ocean Odyssey reader, you’re probably already familiar with some of New England’s endangered marine species—Atlantic salmon, leatherback sea turtles, and North Atlantic right whales, for example. You also know how important protecting important habitat areas can be to the conservation and recovery of these incredible animals.

In honor of Endangered Species Day, we thought we’d introduce you to one of New England’s weirder endangered species: sturgeon.

There are actually two species of sturgeon found in New England—shortnose sturgeon and Atlantic sturgeon. Once, sturgeon were so common in east coast streams and coastal waters that settlers considered them a navigational hazard, since they tended to leap out of the water and directly into passing boats.

These once-plentiful sturgeon populations have declined sharply since the 1800s due to overfishing for meat and caviar. Shortnose sturgeon have long been considered endangered throughout their entire range, which stretches from New Brunswick to Florida. The Atlantic States Marine Fisheries Commission and the National Marine Fisheries Service placed a coast-wide moratorium on catching Atlantic sturgeon in 1998. In 2012, most populations of Atlantic sturgeon were also placed on the endangered species list, with the exception of the Gulf of Maine population, which is listed as threatened.

Sturgeon are basically living fossils and are one of the oldest existing families of bony fish—they’ve been around since the Cretaceous period, 120 million years ago. They don’t have scales, but are covered with bony plates called scutes. Atlantic sturgeon can reach an insane 60 years old and fifteen feet long. Within the past month, a six-foot sturgeon washed up in the Delaware River and a seven-foot sturgeon washed up in the Connecticut River—and both of these fish were just juveniles.

Atlantic sturgeon are anadromous, meaning they split their time between freshwater and saltwater. Generally, sturgeon remain in brackish streams until they’re about six years old. They then reach maturity in the ocean before returning upstream to spawn. Female sturgeon don’t spawn until they’re about 15 years old and only spawn once every 2-6 years, meaning populations are slow to grow and recover. Sturgeon larvae also need cool, clean, flowing water to survive, making upstream habitat restoration a crucial part of sturgeon recovery.

Interested in learning more about these endangered fish? NOAA is holding an Endangered Species Day Sturgeon Tweet Chat with NOAA Fisheries Scientist Jason Kahn today from 2-3 p.m. ET. Tweet @NOAAFisheries with the hashtag #ESDaychat to join in.

Lined sea anemones off Cape Ann by Alex Shure. http://www.shureunderwater.com/
Lined sea anemones off Cape Ann by Alex Shure. http://www.shureunderwater.com/
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A charming nightmare? With the lined sea anemone perspective matters.

Categories: Creature Features

Look at this tiny wonderland of delicate, star-shaped, fair-haired anemones – benignly filtering food from the water and setting a lovely ocean ambiance. They could be little whisks that a mermaid might use to make a soufflé. Peaceful, right? Wrong. These dudes are remorseless, parasitic death-bringers who drill into their hosts and eat all their food. Which makes me love them a lot, really.

These lined sea anemones (Edwardsiella lineata) spend part of their lives anchored to the bottom of the ocean, doing what most anemones do, sitting around and eating what the current brings them. Before that, however, when they are but wee larvae, they go on a search-and-destroy rampage of their favorite host, a ctenophore known as the sea walnut, or warty comb jelly. We have lots of ctenophores in New England – you can see them in action in this short video by Alex Shure. Ctenophores may seem pretty hardy in this big swarm, but they are no match for the larval lined sea anemone.

 

Jelly Attack! from Green Diver on Vimeo.

It’s not just what this tiny assassin does, it’s how. Mayhem is a polite word for it. As Casey Diederich, my favorite marine biologist for fact-checking blogs about demented goings-on in the ocean, points out:

“The parasitic larva kind of hangs out in/near the pharynx, part of the digestive cavity of the ctenophore, to steal its food. This means that it must have some way to evade digestion by the ctenophore. If you could evade digestion, why not just enter through the ctenophores mouth? Apparently, the parasitic larva burrows through the outside of the ctenophore, then migrates through the ctenophore’s mesoglea (the “jelly” found in  jellyfish, ctenophores, and other kinds of marine invertebrates), and canal system until it gets to the ctenophore’s gut/pharynx. WHAT??? Nature is a crazy motha.”

And, yes, “crazy motha” is a technical marine biology term.

This is probably not much fun for the ctenophore, which can play the unwilling host to several of these baby anemones at a time, but it’s not all bad news, depending on your perspective.

First of all, the parasitic infection prevents the comb jelly from thriving, and thus reduces its population over time. Ctenophores eat zooplankton, including tiny juvenile fish, like cod and flounder. So it’s possible that the parasitic action of the anemone is helping more of these little fish not get eaten and make it to adulthood. More food for us! In some places over half the local comb jellies are infected with the parasitic anemone.

Secondly – in the northeastern Atlantic, off the coast of Europe, these comb jellies are invasive, and really taking a toll on the native wildlife, so the lined anemones might be preventing even worse devastation to the fisheries in that neck of the ocean.

So, the anemones are the good guys? Well, hold on. The larval form of the lined anemone has been implicated as one of the animals that can cause the annoying “sea-bather’s eruption” – an itchy rash you get sometimes after you swim in the ocean. Also, given how successful they are at life in general, there is concern that the lined anemones themselves might become an invasive nuisance in the northeastern Atlantic.

I guess there are no easy conclusions to draw here. Still, I think it’s safe to say that if these types of animals had blood, the lined anemone’s would be cold. One cold-blooded, crazy motha.

lobsterwhalen
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Maine’s Most Lucrative Fishery Threatened by Pesticides?

Categories: Creature Features

Last month, Maine legislator Walter Kumiega introduced a bill that would ban the use of two pesticides, methoprene and resmethrin, in any body of water or area in the state that drains into the Gulf of Maine. We’re all familiar with some of the negative consequences of certain pesticides—from DDT’s effect on birds described in Rachel Carson’s Silent Spring to the more recent concerns about some chemicals’ role in crashing honeybee populations. But Kumiega’s bill is unusual in that it seeks to protect a marine species, not a terrestrial one—lobsters.

Lobsters are by far Maine’s most valuable fishery. In 2012, the state landed 126.6 million pounds of lobster with a value of over $340 million, and around 80% of the state’s fishing revenues currently come from these tasty crustaceans. This heavy reliance on one species means that Maine’s fisheries are very vulnerable to any natural or human change that might harm the lobster population.

A crash in the currently abundant lobster population is a very real possibility, as fishermen in Long Island Sound know well. Connecticut and New York once had booming lobster fisheries. In 1998, for example, Connecticut landed over 3.7 million pounds of lobster, while New York landed nearly 7.9 million pounds. But that fishery collapsed rapidly over the past 15 years. In 2012, Connecticut caught just 241,000 pounds of lobster, and New York caught just 270,000 pounds.

This precipitous crash in the lobster fishery has been linked to two factors. First, climate change has led to warmer water temperatures in Long Island Sound. The area was already the southern edge of lobsters’ range, and areas that were once hospitable to lobsters quickly became too warm. A Massachusetts state biologist recently told a group of fishermen that he doubted lobsters would recover in waters south of Cape Cod any time soon, because water temperatures are simply so high that lobsters have moved north or farther offshore to lay their eggs. In addition, higher water temperatures may make conditions more favorable for the spread of a shell disease that makes lobsters unfit for sale.

Water temperatures aren’t the only thing linked to the lobster crash, however. During the 1990s, two pesticides were sprayed extensively in the New York area to control the mosquitoes that carry West Nile virus. These chemicals were later identified in the tissues of dead lobsters in Long Island Sound. Despite the claims of government scientists that there is not enough evidence to link pesticides to the lobster decline, in the mid-2000s, three chemical companies reached multimillion-dollar settlements with lobstermen for their role in the die-off. Pesticides have also been blamed in a smaller die-off in New Brunswick’s Passamaquoddy Bay.

This takes us back to Maine’s proposed bill. Methoprene and resmethrin are apparently used sparingly in Maine and have not been used by state agencies, but Kumiega says the legislation is a preventative measure to protect the state’s valuable lobster fishery. Some, however, are concerned the bill does not go far enough and might provide a “false sense of security.” The executive director of the Maine Lobstermen’s Association told the Portland Press-Herald that lobstermen worry banning two pesticides could limit research into other environmental changes and pollutants that could harm the lobster fishery. They want a more thorough analysis of which pesticides might harm lobsters, and the state seems to agree—the Department of Marine Resources is considering a sediment survey of Casco Bay to assess the presence of pollutants.

With such a large portion of Maine’s fishing revenues dependent on lobsters, more research into what could deplete their population–whether it’s fishing pressure, climate change, or pesticides—will be critically important. Connecticut and New York have already lost a once-thriving fishery, and Maine’s marine ecosystems and coastal communities can’t afford to do the same.

Northern anemones are one of the many kinds of invertebrates found at Cashes Ledge.
Northern anemones are one of the many kinds of invertebrates found at Cashes Ledge.
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It Takes a Village: Life on the Bottom at Cashes Ledge

If you’re reading this post, you are probably a vertebrate. Those of us with spines and bones may find it hard to empathize with invertebrates (animals without spines), with their radically alien ways of being, frequent radial symmetry and general facelessness! But in many ways, invertebrates are the heart of ocean ecosystems, so for those of us interested in the fascinating universe of the sea it is important to understand them. And there are few better places to study invertebrate communities than one unique and now threatened special area in the Gulf of Maine.

Off the New England coast, about 80 miles due east from Cape Ann, lies Cashes Ledge: an undersea mountain range that is one of the most dynamic, and ecologically productive areas in the entire North Atlantic. Although only the most intrepid divers have seen Cashes Ledge with their own eyes, you can imagine the undersea terrain by thinking of mountains that you already know: as a multifaceted terrain of rocky peaks, banks, and channels, with a valley floor of mud, gravel, sand, boulders, and rock. This terrain supports a vibrant bottom-dwelling community of bright orange, red, and yellow sponges, sea stars, brittle and feather stars, sea squirts, sea pens, anemones, tube worms, northern shrimp, horse mussels, and sea mosses, technically known as “bryozoans.”

This colorful community is one of Cashes Ledge’s treasures, and one that is ever more in peril.

Invertebrates of Cashes Ledge. Photo by Jon Witman.

Invertebrates of Cashes Ledge. Photo by Jon Witman.

 

The variety of terrain at Cashes Ledge makes it an ideal living laboratory for studying the structure of the vibrant communities that grow along its slopes and hills. The enhanced water flow created by the topographic “ramp” of the Ledge encourages a high growth rate of invertebrates, both mobile and encrusted to their home rocks—varieties of sponges that are as yet uncatalogued, including a rare species of blue sponge that has only ever been sighted in the rock wall communities of Cashes Ledge.

Unique communities form at each depth, creating a complex and rich diversity of species. Metridum anemones gather at the tops of the ridges, sheltered by waving groves of laminarian kelp. Large urticina anemones and orange sea stars flourish in the mid-depth areas, as well as brachiopods, crinoids, ascidians, and yellow mounding sponges the size of footballs. The soft bottom is home to tube worms, pink northern shrimp, and thickets of mud anemones. Ammen Rock, the highest peak in the Cashes Ledge range, hosts large, sensitive beds of horse mussels: a “foundation species” because they provide habitat and refuge for other species.

Phakelia sponge and brittle stars. Photo by Jon Witman.

Phakelia sponge and brittle stars. Photo by Jon Witman.

The biological richness which makes Cashes Ledge so compelling for scientists to study has also drawn the attention of industrial fishing interests, which are currently lobbying to remove long-standing protections for Cashes Ledge.  Allowing bottom trawling at Cashes Ledge would rapidly deplete the remaining populations of large cod and other groundfish who are the most prolific spawners. The kelp forests, slopes and rocky terrain serve as excellent habitat and the best chance for restoring Gulf of Maine cod populations, which are now at historically low numbers.

Cod and anemones. Photo by Stellwagen Bank National Marine Sanctuary.

Cod and invertebrates. Photo by Stellwagen Bank National Marine Sanctuary.

New bottom trawling would be bad news for bottom-dwelling sea life at Cashes Ledge, because a number of the invertebrate species that grow there are particularly vulnerable to human disturbance. These invertebrates move slowly (if at all), and often have specialized reproductive cycles. If their habitat is harmed and breeding adults removed, species could take many years to recover, even longer for rarer species. Scientific estimates predict that the large, solitary sea anemone Urticina crassicornis would take 268 years to return to the community if it were removed by fishing gear.

Trawling Cashes Ledge could deplete or endanger many species that we do not yet fully know about. Cashes Ledge should be left intact as a resource for scientists, as well as a replenishment zone whose presence will sustain a recovering ocean ecosystem that will be of benefit to fishermen in the future. Trawling at Cashes Ledge is a short-term economic gamble that would cause long-term economic and environmental damage.

Cashes Ledge is a “wild offshore place that helps us understand how marine ecosystems tick,” says marine ecologist Jon Witman, who has been studying it for 35 years. “Cashes Ledge provides an opportunity to understand why biodiversity matters in an ecological sense. Unfortunately,” he continues, “we are losing marine biodiversity in the world’s oceans faster than we can study it.”

As an offshore haven far from the polluted waters of coastal habitats, Cashes Ledge warrants full and permanent protection to ensure that its intricately connected habitats and unique ecosystem can continue to serve as a reservoir of diverse ocean wildlife, a replenishment zone for sustainable fish stocks, and an open ocean laboratory for scientific research. Please add your voice to those calling for the protection of Cashes Ledge.

Laura Marjorie Miller writes about travel, ocean conservation, Yoga, magic, myth, fairy tales, photography, and other soulful subjects. She is a regular columnist at elephantjournal, a writer at UMass Amherst, and a travel correspondent for the Boston Globe. Her writing has appeared in Parabola and she has features forthcoming in Yankee Magazine and Seven Miles of Steel Thistles. She is based in Massachusetts, where she lives with a cat named Huck.