An Ocean Warming: Ocean Acidification, Lobster, and the Need for More Research

Year after year, temperatures in the Gulf of Maine’s waters have risen at unprecedented rates, a result of the same increased concentrations of atmospheric greenhouse gases (primarily carbon dioxide derived from human activity) responsible for climate change.

This has caused a slew of problems for the marine life in the area – and it also means serious trouble for the ocean’s biogeochemical composition. The ocean has always served as Earth’s largest “carbon sink,” meaning that naturally occurring and industrially produced carbon dioxide is dissolved into seawater and, through a chemical synthesis process, forms carbonic acid.

Carbonic acid breaks down into ions that increase the ocean’s acidity. Over time, marine species have evolved alongside this process in a steady transformation leading to a balanced pH for the ocean.

But, as humans have deepened their addiction to climate-warming fossil fuels, more and more carbon dioxide is being pumped into the atmosphere – meaning the ocean is taking on more carbon dioxide than ever before. These drastic increases change the ocean’s pH level, throwing it off balance and making it more acidic.

Learning as we go

The full effects of ocean acidification are not yet entirely known, but we have begun to see its effects on certain species. The group of species most threatened by ocean acidification are some of the most important to New England’s coastal economy: the ‘calcifiers’ – lobsters, scallops, oysters and other fish that use the carbonate and calcium ions dissolved in seawater to build their shells.

As the water becomes more and more acidic, it becomes harder to for these species to make and maintain their shells. And as they devote more energy to constructing their shells, less energy can be given to other essential processes, like eating or reproduction.

An uptick in shell disease threatens the fishery

For the American Lobster, ocean acidification has been shown to have devastating effects on the growth and shell building rates of juveniles, making them significantly more susceptible to threats like predation and disease.

A shell disease that creates unsightly lesions in the lobster’s hard exoskeleton, for example, had previously been thwarted by colder water temperatures. But that disease has now slowly begun to creep its way up the coast and into the Gulf of Maine. Given the increasing vulnerability of lobsters, and juveniles in particular, this shell disease and other threats have the potential to inflict serious harm on the species, the fishery, and New England’s economy as a whole.

A Lesson in Taking Initiative

The threats facing our oceans due to ocean acidification have prompted several states to take the initiative to begin to address the regional impacts of coastal and ocean acidification. This spring, Massachusetts senators and representatives are working on a bill that will create a special commission to examine the existing and potential effects of ocean acidification on both ecologically and economically important species in the waters off of Massachusetts.

This bill, Resolve H. 716, follows a rough framework laid out by states like Washington and Maine who have already approved commissions to confront the threats of ocean acidification.

In a recent roundtable forum, Massachusetts Congressman Bill Keating emphasized that thorough research on ocean acidification is critical because without the best scientific knowledge, it is impossible to know how Massachusetts should take action.

Following in Washington’s footsteps is an excellent starting point for this work, however the situation facing Massachusetts and Maine (and New England at large) is unique. In the Gulf of Maine, scientists are witnessing changes in temperature and pH more rapidly and dramatically than almost anywhere else in the world – and its waters face a unique stressor due to the arctic ice melt and the resulting influx of freshwater. On top of the environmental factors, New England is especially vulnerable due to its economic dependence on susceptible species such as lobster.

Next Steps

There’s no question that establishing a devoted task force to study ocean acidification and what it means for the people and species in Massachusetts and New England will be helpful. With the support of strong science and the engaged voices of all stakeholders, addressing New England’s unique ocean acidification challenges is an important step in addressing climate change in our region.

Celebrating New England Lobsters on National Lobster Day

Cashes Ledge Lobster
A lobster at Cashes Ledge. Photo courtesy Brett Seymour/CLF

If there’s one thing we can be sure of, it’s that New Englanders love lobster. It’s weaved into our culture and history, and it’s unimaginable to think of New England without this famed summer seafood.

Few know that lobsters were once so plentiful in New England that Native Americans used them as fertilizer for their fields, and as bait for fishing. And before trapping was common, “catching” a lobster meant picking one up along the shoreline!

During World War II, lobster was viewed as a delicacy, so it wasn’t rationed like other food sources. Lobster meat filled a demand for protein-rich sources, and continued to increase in popularity in post-war years, which encouraged more people to join the industry.

Popular ever since, now when most people are asked what comes to mind when they think of New England, seafood – especially lobster – is typically at the top of the list.

An industry under threat

We love our New England lobster, but there’s evidence suggesting they’re in danger of moving away from their longtime home. That’s because lobster is under threat from climate change, the effects of which can already be seen on this particular species.

The Gulf of Maine is warming faster than 99% of ocean areas. Until last winter’s uncharacteristically cold temperatures, the prior few years saw an increase in catchable lobster – as the warmer temperatures cause them to molt early, and they move toward inshore waters after molting. However, continued warming will ultimately encourage the lobsters to move north to find colder waters, where they spend the majority of their time.

This is already happening in southern New England, where the industry is already suffering, seeing lobsters migrating northward.

And we’re still learning about the potential for damage caused by ocean acidification, as well as how lobsters may be affected by an increase in colder than usual New England winters.

As we celebrate one of New England’s iconic species on National Lobster Day, let’s remember that slowing down climate change is an important priority for ensuring that future generations can enjoy not Canadian or Icelandic lobster, but New England lobster. Click here to support Conservation Law Foundation’s efforts on fighting climate change.

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.

Image credit: Benjamin Wilson, Flickr

Maine’s Most Lucrative Fishery Threatened by Pesticides?

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.

Photo credit: Z. Whalen

Announcing Our November Photo Contest Winner!

Congratulations to Zach Whalen, our winning photographer for November’s contest! We love this unusual view of a common sight in New England’s waters and the way it showcases the spectacular coloring of a northern lobster.

Do you have a great photo of New England’s oceans to share?  Enter our photo contest! Each month, Brian Skerry will lead our team of judges to select a winner, who will receive a copy of Brian’s book Ocean Soul.

Entering is easy! Explore New England’s oceans, take some photographs and then share them with our online community on Flickr™. All you need to do is add your photos to the New England Ocean Odyssey group and tag them “PhotoContestNEOO”. Find out more here.

Be sure to check our our New England Ocean Odyssey Facebook page where we’ll continue to post honorable mentions from the photo contest and other great ocean photography.

We look forward to seeing your photos!

The New Signs of Spring

Spring has sprung, New England style. All the signs are there – the crocuses came up then got covered by sloppy, wet snow, and there’s a bunch of mud underneath it all. What New Englander doesn’t love this time of year? We get to think about shedding our winter wrappings and revealing our tender flesh to the warmer weather.

This happens in the ocean, too. Maine lobsters typically molt (shed the old shell and grow a new one) in the spring, as the water gets warmer. Lobstermen know this, and structure their fishing time around it. Richard Nelson, a lobsterman in Friendship, Maine, says he tries to catch the hard-shell lobsters in early spring before the molting starts, and then starts catching the new shedders right around when the summer tourists show up. The shedders are easier to eat, with their softer shells, and are sweeter tasting. But the shedders are also more fragile, and can’t be shipped very well, so they need to be eaten locally or sent to a processor.

“Lobstermen usually look forward to the shedders as newfound abundance,” said Richard. Lobsters that were previously too small to keep are bigger after they’ve shed, and are more likely to be of legal size. Normally, the appearance of the shedders is good news, but last year the lobsters in Maine were molting a month earlier than usual, which threw a monkey wrench into the whole fishing season. The tourists weren’t there yet to eat the shedders, and the processors were busy with Canadian lobsters, so they couldn’t take the Maine product.

And there are signs that it’s happening again this year, according to Bob Bayer, Executive Director of the Lobster Institute at the University of Maine. Warmer than usual ocean water could be driving the lobsters from their deeper winter homes towards their shallower molting grounds too early for the summer tourists and processors to consume.

This is not the only change we’re seeing. According to Bob, there is a lobster population boom underway from north of Cape Cod well up into Canada. They are increasing in number from year to year, to the point that they are might be overcrowding the ecosystem, which might make them more vulnerable to disease and is possibly leading to cannibalism.

Why are there so many lobsters? Bob thinks there might be few factors at play. First, he thinks it’s possible that water pollution south of Cape Cod might be inhibiting lobster recruitment, while waters to the north are cleaner. Temperature is probably a factor as well, for a couple of reasons. First, lobsters grow more quickly in warmer water. Newly hatched lobsters spend their larval stages near the surface of the water, where they are more exposed to predators, and have to develop adequately before they can settle on the relative safety of the ocean floor. When they grow faster, they reach safety faster. The second reason temperature could be helping lobster populations to increase is that warmer waters can increase the amount of food available to lobsters, which fuels their faster growth –  they only grow quickly if there is enough to eat.

If you add it all up – warm, clean water with lots to eat, you get population growth. What usually keeps growth from becoming a boom is predators – in this case, fish like cod and haddock. Cod and haddock, you’ve probably heard, are not having a population boom. So with fewer things around to eat them, except for hungry tourists – and there’s a short season for those – the lobster continue to boom.

Spring is a time of change, of re-growth and renewal. It is also turning into a time of more bad news for New England lobstermen, who depend on a healthy lobster population with a predictable seasonal molt to make a living. Last year, even with the abundance of lobsters in the sea, fishermen struggled with low market prices due to the glut of product. The entire ecosystem in our New England waters is shifting, and it’s anybody’s guess how things will end up, but it seems clear that making a living from the sea is becoming more unpredictable.