Shell fish dying from red tide – Massachusetts – 06/28/2005

  • October 29, 2013 at 6:13 pm #784

    I think the time to be “wondering” is over. Gosh, don’t these people
    talk to each other, or even do the research?
    We’ll see if waht is mentioned in the last paragraph becomes true.
    I’ll be looking for some break in the algae out-breaks.
    You all keep your eyes and ears open too.
    algae bloom is red flag
    Northeast’s red tide prompts concerns

    By Carolyn Y. Johnson
    The Boston Globe
    Published June 15, 2005
    BOSTON — As Massachusetts officials scramble for disaster relief
    for shellfish farmers strapped by the worst bloom of red tide in
    decades, scientists are trying to figure out whether the toxic algae
    explosion hints at an ecological disaster.

    Red tides appear to be on the increase worldwide, fueled in many
    cases by nutrient runoff that comes with booming economic
    development along the coasts. New England’s bloom, spotted in May,
    extends from the Gulf of Maine to Cape Cod and shows no signs of

    “This is unlike anything we have observed before, and the situation
    is still unfolding. We don’t fully understand why it’s so bad this
    year,” said Dennis McGillicuddy, deputy director of the Woods Hole
    Center for Oceans & Human Health.

    So far, scientists think the huge bloom of microscopic, single-
    celled organisms is a natural response to a series of events: Spring
    weather pushed the algae toward shore. There, the algae fed off
    nutrients in freshwater from the heavy winter’s melt and spring
    rainfall. More recently, the late spring sunlight has caused a
    growth explosion.

    The combination “is like sprinkling fertilizer on a lawn,” said
    Peter Borrelli, executive director of the Provincetown Center for
    Coastal Studies.

    Scientists are concerned that the spreading bloom may seed waters
    where red tide never struck before, as it did in Nauset Marsh in
    1978. Since then, the marsh along Cape Cod has had its own annual
    red tide, which appears to be worsening as nearby development
    increases. The same thing seems to be happening in Asia.

    “Red tide is a natural phenomenon. It happens periodically,” said
    Bob Prescott, director of the Massachusetts Audubon Society’s
    Wellfleet Bay Wildlife Sanctuary. “But is it exacerbated by the
    number of people who live along the coast? Is that in some way
    fueling this whole outbreak? You just don’t know until it’s all

    Alexandrium fundyense, the algae species that causes New England’s
    version of red tide, is poorly understood. Even its most widely
    known attribute–it produces a potent neurotoxin–is largely a
    mystery. Scientists are divided as to whether the toxin, called
    saxitoxin, protects the cells from plankton predators or has no
    purpose at all.

    Mussels, clams and oysters, which are all filter-feeding mollusks,
    can suck in about 2 1/2 gallons of seawater an hour, straining their
    plankton meals 24 hours a day. The toxin accumulates as it feeds and
    can concentrate enough in a single shellfish to sicken or kill a
    person who eats it.

    Lobster and most fish don’t filter feed, so they don’t take in
    enough algae to become ill.

    The tiny algae spend months, sometimes years, in a ball-like form
    known as a cyst, buried in sediment on the ocean floor. Those single
    cells then divide to form hundreds of microscopic cells floating
    near the surface of the ocean. Scientists are trying to understand
    these cysts well enough to stop them.

    During a research cruise last year, scientists found a significant
    increase in cysts since their last survey in 1997.

    To ensure public safety, Massachusetts biologists have closed much
    of the state’s shoreline to shellfishing.

    Fortunately, New England’s red tide is relatively benign compared
    with the species found in Florida, which kills fish and manatees,
    and can release an airborne toxin that causes respiratory problems
    in people.

    This week, a team from Woods Hole plans to sail south to see whether
    the algae are spreading beyond Nantucket and Martha’s Vineyard.

    Usually, midsummer is the end of red tide season. Blooms subside as
    the water warms, so fewer nutrients remain in the top layer of the
    ocean. When the algae are starved, they stop growing and begin
    sexual reproduction, creating a cyst, which falls to the bottom of
    the ocean–to haunt shellfish farmers another day.

    Globe writer Beth Daley contributed to this report.

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