Lobster Die-Off Spreads To Other Sea Life

Subject:     Lobster Die-Off Spreads To Other Sea Life----
Date:       Thu, 11 May 2000 13:31:08 -0400
From:        Stephen Tvedten <steve@getipm.com>
Organization:     Get Set Inc. (www.getipm.com)

To:     Lyndon Hawkins <hawkins@empm.cdpr.ca.gov>
          Senior Research Scientist
          State of California, Department of Pesticide Regulation - Integrated Pest Management

Dear Lyndon, I thought you might like to read an article entitled: Lobster Die-Off Spreads To Other Sound Sea Life - By JANE E. DEE, The Hartford Courant, May 11, 2000.

More than lobsters are dying in Long Island Sound in what some scientists are calling one of the most severe ecological disasters to strike the East Coast.

Spider crabs, sea urchins and starfish also have been found dead in hundreds of lobster pots pulled from the water recently.

``I think it should be a warning to all of us about what we are putting in the water,'' said Paul DeFur, a University of Connecticut scientist who has conducted toxicology tests on tissue taken from dead lobsters. ``Out of sight, out of mind is not a responsible way of thinking.''

Concerned scientists from across New England who first shared ideas at a symposium last month are stepping up their examination of the unprecedented die-off, which started in 1997 and culminated last fall with massive numbers of dead lobsters.

Many factors, including pollution, may be contributing to the deaths, scientists say. And while a parasite known as a paramoeba has been identified as a cause of death, the full explanation remains elusive.

Scientists, who are just beginning to gather data on the deaths of other shellfish, believe the results might illuminate the bigger problem of what is happening in the Sound. Lobster fishermen say they have found as many dead crabs as lobsters in their traps.

Long Island Sound is one of the country's largest and most heavily populated estuaries, with about 20 million people living along its shores. It is relatively enclosed, with little circulation, especially at its western end, where the lobster mortalities have been highest.

Although state officials agree that the die-off is a catastrophe, they say the overall health of the Sound is improving.

``Certainly this is a disaster for the lobster fishery,'' said David Leff, deputy commissioner of the state Department of Environmental Protection. ``But we shouldn't let this color our perceptions of the entire Sound, as well.''

But while the Sound is the cleanest it has been in years, scientists studying the marine life mortalities say it should be considered a sentinel body of water, warning of problems that can occur as a result of pesticides, sewage and other pollution.

``I've been involved in a lot of work in New York and Massachusetts, but this is something that is alarming,'' said Lance L. Stewart, an associate extension professor with the college of agriculture and natural resources at the University of Connecticut. ``Lobsters, by nature, have been very resilient, so this worries us.''

Scientists are focusing on several possible agents that could be contributing to the die-off, including a chemical compound and a larvicide that appear to inhibit lobster's reproductive systems, and chlorine from sewage treatment plants.

DeFur is examining how chemical compounds that occur when detergents break down in sediment may be affecting the Sound. Detergents can enter the Sound after being poured down sink drains and passed through sewage treatment plants.

The compounds, nonylphenols, interfere with the endocrine hormones of some marine organisms, inhibiting their reproduction, DeFur said.

Scientists have documented the adverse effects of nonylphenols on finfish, but more research is needed to determine the effect they might have on crustaceans, DeFur said.

State officials say, however, that the chance of chemicals entering the Sound is slimmer now with upgrades in sewage treatment plants. The Sound is cleaner than ever despite the 85 treatment plants in Connecticut that each day pour 450 million gallons of treated sewage into rivers that flow into the Sound, they said.

John Makowsky, a fourth-generation lobsterman who fished the waters behind the Norwalk Islands before the lobster kill, said he believes rain ``is the delivery system of something toxic'' into the Sound.

Whatever is killing the lobsters in his traps also has destroyed the slime and sea grass that clings to his ropes, Makowsky said, adding that he believes chlorine from the treatment plants is to blame. Makowsky, 49, said he can no longer make his living from the sea and has returned to school.

But state officials said they do not believe chlorine used to treat sewage is seeping into the Sound in harmful levels. Paul Stacey, a water quality expert with the DEP, said a 1988 toxicity study in Stamford by the federal Environmental Protection Agency determined there was not enough chlorine in the water to be toxic to organisms.

However, Stacey said, ``you can never rule out the possibility that something at low levels is weakening the lobsters and making them susceptible to disease.''

Pesticides, including those used to battle mosquitos, are also being studied for their possible role in the die-off.

Hans Laufer, a UConn professor emeritus, said he became alarmed after listening to lobstermen describe finding egg-bearing lobsters that had molted before their eggs hatched, in effect shedding their eggs along with their shells.

Laufer, who has studied reproductive hormones in crustaceans for 20 years, questioned the use of one larvicide that interferes with a mosquito's ability to molt. Insects, Laufer said, are biologically related to lobsters.

The larvicide, methoprene, is known to harm small crustaceans, Laufer said. It acts in a similar fashion as nonylphenols, disrupting endocrine hormones and interfering with reproduction.

``In mosquitoes, it acts as an anti- hormone, and that's what's killing them,'' Laufer said. ``It's doing exactly the same thing to lobsters, exactly the same.''

In New York state, where methoprene has been used for years, officials acknowledged that the larvicide's impact on sea life needs to be studied. But for public health reasons, the state still plans to apply the methoprene to hundreds of catch basins this year, said Mark Lowery, spokesman for the New York Department of Environmental Conservation.

Connecticut officials also plan to use methoprene to control mosquitoes, because scientific research has not yet proved that the larvicide is harmful to lobsters.

``I would agree with the scientists that we don't know for sure what is causing the die-off, and that we should continue to make inquiries to eliminate and confirm what factors are contributing,'' Leff said. ``But there is not enough evidence now on which to base public health policy.''

Despite the current inquiry, the cause of the lobster deaths might never be known.

``There's a big black hole out there as to what caused this,'' said Richard French, a UConn pathobiologist who identified the paramoeba.

As for the lobster die-off that has crippled the state's $13 million lobster industry and put many longtime fishermen out of work, French said, ``There might not be anything we can do. It may be too late.''

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