Mystery ailment killing dolphins, manatees, pelicans – 01/07/2014

  • January 20, 2014 at 11:33 pm #2177

    Indian River Lagoon mystery ailment killing dolphins, manatees, pelicans
    Tampa Bay Times

    The Indian River Lagoon on Florida’s east coast has long been known as
    the most diverse ecosystem in North America.

    Its 156 miles of water boast more than 600 species of fish and more than 300
    kinds of birds.

    The lagoon is not just an ecological treasure. To the towns along its edge —
    Titusville, Cocoa, Melbourne, Vero Beach and Stuart, among others — it accounts
    for hundreds of millions in revenue from angling, boating, bird-watching,
    tourism and other waterfront activities.

    Scientists puzzled by manatee deaths on Florida’s east coast

    3 Months Ago – Florida’s vanishing springs

    7 Months Ago – Red Tide fades; manatee population down about 10 percent

    2 Months Ago – Red Tide study shows toxins, potential benefits

    More than a Year ago – U.S. Sugar deal crucial for Everglades, group says

    More than a Year ago. But these days the Indian River Lagoon has become known as a
    killing zone.

    Algae blooms wiped out more than 47,000 acres of its sea grass beds, which one
    scientist compared to losing an entire rainforest in one fell swoop.

    Then, beginning last summer, manatees began dying. As of last week, 111 manatees
    from Indian River Lagoon had died under mysterious circumstances. Soon pelicans
    and dolphins began showing up dead too — more than 300 pelicans and 46 dolphins
    so far.

    How bad is it? In the past week, a dolphin a day has turned up dead in the
    lagoon, said Megan Stolen, a research scientist at Hubbs-SeaWorld Research

    “When you lose the manatees, pelicans and dolphins, you know something is going
    on,” said Marty Baum of Indian Riverkeeper, a nonprofit environmental group that
    tries to act as a steward for the lagoon and the Indian River that flows into

    Yet so far nobody can name the killer. Biologists have some suspicions but are
    baffled about any connection among the species’ problems. The diets are
    different: Manatees are vegetarians, while pelicans and dolphins eat fish. The
    symptoms are different: The manatees’ stomachs are stuffed, while the pelicans
    and dolphins are emaciated.

    Baum’s family has lived around the lagoon since the 1860s, but he can’t remember
    anything like this ever happening.

    The lagoon has had algae blooms before. None of them were like the one that hit
    it in 2011. Experts called the explosion of the greenish Resultor species a
    “superbloom” because it covered nearly 131,000 acres and lasted from early
    spring to late fall.

    Then came the “brown tide” algae bloom last summer, tinting the water a
    chocolate brown. The algae, Aureoumbra lagunensis, have been a recurring problem
    in Texas. Why it suddenly showed up in Florida is another mystery.

    The algae blooms shade out sunlight needed by sea grass. By the time the algae
    was done, the lagoon had lost more than half its sea grass, essential to
    nurturing fish and other marine species.

    Then came what Pat Rose of the Save the Manatee Club called “a cascade of

    The mysterious manatee die-off began in the northern part of the lagoon last
    July, hit its peak around March and now produces another dead manatee about
    every two weeks, said Martine DeWit of the Florida Fish and Wildlife
    Conservation Commission.

    Biologists at a state laboratory in St. Petersburg examine every dead manatee
    that’s found in Florida for a cause of death. But the Indian River Lagoon
    manatees have them stumped. The manatees appeared to have abruptly sickened and

    Normally manatees eat sea grass. With much of the sea grass gone, the manatees
    turned to eating a red sea weed called gracilaria. But so far there is no sign
    that played any role in their deaths, DeWit said. The lab is continuing to test
    for viruses, pollutants or something else.

    Similar tests are being run on the dead pelicans and dolphins. Stolen of
    Hubbs-SeaWorld said the dolphin die-off first became evident in January and has
    not let up since.

    And the lagoon’s 700 dolphins are already somewhat beleaguered. They tend to
    suffer from high levels of mercury. In fact, research by the Harbor Branch
    Oceanographic Institution at Florida Atlantic University has found that there’s
    so much mercury in the lagoon’s fish that people who eat them have higher
    mercury concentrations in their tissues than those who eat imported fish.

    Scientists caught a break Friday when a kayaker discovered an ailing, sunburned,
    underweight dolphin stranded in the shallows, Stolen said. Rescuers were able to
    capture it for rehabilitation, and they hope it offers clues to what killed the

    When it comes to naming the cause, the list of suspects rivals a game of Clue.
    Stormwater runoff filled with fertilizer and other nutrient pollution has been
    blamed for fueling the algae blooms. Other theories point to the U.S. Army Corps
    of Engineers dumping polluted water from Lake Okeechobee, changes in water
    temperature or salt levels, overflow from contaminated mosquito-control ditches,
    even climate change, which is boosting the acidity of the world’s oceans.
    The Harbor Branch Oceanographic Institute had hoped for $2 million in state
    money this year for a study of the lagoon’s water chemistry, but Gov. Rick Scott
    vetoed the appropriation.

    There are a few hopeful signs. The pelican die-off appears to have ended. As for
    the sea grass, “we’re starting to see some regrowth in certain areas, but not as
    much as we’d hoped,” said Tony Rice of the Indian River Lagoon Estuary Program,
    a government-sponsored partnership among local and state agencies.

    Meanwhile, a new brown tide bloom was spotted last month. If the lagoon hasn’t
    hit a point where it’s sliding toward oblivion, said Rose, of the Save the
    Manatee Club, a return to normal is a long way off. “I’m thinking it’s seven,
    eight, nine years,” he said. “We could be looking at a decade before it

    Craig Pittman can be reached at


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