Herring die-offs in puget sound – 04/02/2005

  • October 21, 2013 at 11:47 pm #658


    Scientists mystified by Puget Sound-area herring decline
    3/29/2005, 4:35 a.m. PT
    The Associated Press

    TACOMA, Wash. (AP) — A steep decline in Puget
    Sound-area herring, a critical food source for larger
    fish, marine mammals and sea birds, has scientists

    Not only are adult herring dying earlier than normal,
    but some fear a stock that used to be one of the
    largest in Washington state’s inland marine waters
    could go extinct.

    The 30-year decline in the small, silvery fish has
    far-reaching implications, said Jim West, a state Fish
    and Wildlife Department research scientist who found
    high concentrations of polychlorinated biphenyls and
    other toxic substances in herring in south Puget

    “Virtually any predator worth its salt in Puget Sound
    is going to be eating herring,” West said.

    Herring are a dietary stable for chinook salmon, cod
    and halibut, and also are eaten by porpoises, seals,
    sea lions and orcas. Freshly spawned herring eggs once
    drew swarms of marine birds, especially diving ducks
    called surf scoters that fly north to nest in the
    Canadian interior.

    “It’s thought to be important for them to feed on
    herring spawn while they’re here because there’s not a
    lot of food up there for them,” said Joseph Evenson, a
    state Fish and Wildlife Department biologist. “They’re
    basically working off their fat reserves.”

    The herring decline may explain the disappearance of
    thousands of scoters from parts of the inland waters,
    said Evenson and his boss Dave Nysewander, the state’s
    marine bird and mammal project leader.

    One of the most severe herring declines is between
    Bellingham and the Canadian border, an area which once
    accounted for about a third of the state’s total

    The Cherry Point stocks plummeted from 10,000 tons in
    1994 to 808 tons in 2000, then rebounded to 1,611 tons
    in 2003, but remain in danger of going extinct, said
    Duane Fagergren, a fish biologist with the state’s
    Puget Sound Action Team.

    In January 2004 the Center for Biological Diversity
    and other activists sought protection for Cherry Point
    herring under the Endangered Species Act. A decision
    from the National Oceanic and Atmospheric
    Administration is expected in mid-May.

    Much of the mystery to scientists is in the high
    percentage of herring that die before reaching the age
    of peak fertility.

    Herring in the inland waters typically used to live as
    long as 5 to 8 years, but now “it’s rare to see one
    over 4,” said Paul Hershberger, a U.S. Geological
    Survey fish pathologist who has been studying disease
    in herring since the mid-1990s.

    In the 1970s, about 20 percent of the sound’s herring
    population died of natural causes annually, but now
    it’s 67 percent to 84 percent, Hershberger said.

    Environmental activists blame pollution and other
    habitat degradation, but state marine fish manager
    Greg Bargmann says disease, lack of food and predators
    also may be involved.

    Hershberger cited the presence of a ichthyophonus, a
    parasite that wasn’t noticed in the inland waters 30
    years ago but is now common and infects the heart and
    other organs, and a virus that causes viral
    hemorrhagic septicemia, which infects mostly young herring.

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