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Scientists puzzled about mysterious disease killing starfish off U.S. West Coast (Radiation???)
http://theextinctionprotocol.wordpress.com/2014/02/10/scientists-puzzled-about-mysterious-disease-killing-starfish-off-u-s-west-coast/
February 10, 2014 – ECOLOGY - A
puzzling “wasting disease” first observed along the west coast of the
United States in June 2013 continues to kill millions of starfish. The
gruesome disease causes the creatures to rot--and to rip their own limbs
off. As one biology professor told PBS Newshour, two infected starfish
he was observing “started ripping themselves apart. The arms just crawl
away from the particular body.” Laura James, a diver and videographer
from Seattle, Wash., and one of the first to notice starfish with the
disease, described a recent dive to Newshour. “There were just bodies
everywhere,” James said. “And they were just like splats. To me, it
always looked like somebody had taken a laser gun and just zapped them
and they just vaporized....We have had now occasional die-offs here and
there, but it's not like this. It's not a mass mortality event.”
Biologists aren't sure what is causing the mysterious disease, which has
now affected 12 starfish species. Pete Raimondi of the University of
California, Santa Cruz, said he believes the starfish wasting disease is
likely caused by a pathogen in the form of a parasite, virus or
bacteria. One theory about the source of such a pathogen is that it came
from the ballast water of foreign ships, as the disease has largely
appeared along major shipping routes. Other theories for the cause of
the starfish die-off include ocean acidification, warming ocean water
making starfish more susceptible to infection and even radiation from
the 2011 Fukushima power plant disaster.
While
the starfish wasting disease cause remains mysterious, one thing is
quite clear: the disease is unbelievably deadly. With a mortality rate
of 95 percent, the disease has completely killed off entire starfish
populations in Puget Sound, off the coast of Washington, and in coastal
areas along California. Starfish are a keystone species, eating
everything from mussels to clams to crab (and even other starfish).
Because they eat so voraciously, starfish have a major impact on ocean
ecosystems. Subsequently, when millions of starfish are wiped out, it
can have a major effect. “These are ecologically important species,”
said Drew Harvell, a marine epidemiologist at Cornell University. “To
remove them changes the entire dynamics of the marine ecosystem. When
you lose this many sea stars it will certainly change the seascape
underneath our waters.” –IST
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