This
is the first mention of radiation as a cause of starfish deaths in
MSM -
"They
are looking for marine biotoxins and viruses and exploring a variety
of possible sources, including radiation from the debris that washed
across the Pacific Ocean after the Fukushima disaster"
Mystery
ailment is wiping out coast's starfish
A mysterious pathogen is wiping out starfish along the Pacific coast, a potential catastrophe that has flummoxed marine biologists who are joining forces to find the culprit.
Peter
Fimrite
9
December, 2013
The
uncontested star of tide pools is disappearing from large areas along
the coast, including Monterey, where the marine invertebrates have
been withering and dying by the thousands.
Nobody
knows what is causing the die-off, but the killer - most likely some
kind of virus, bacteria or pollutant - is widespread and extremely
virulent. It has ravaged a variety of starfish species in tide pools
and in deeper water along the coast from Mexico to Alaska.
Pete
Raimondi, a marine biologist and lead researcher on a team of
scientists, laboratory technicians and geneticists, said he has seen
90 percent of the sea stars, as the multi-armed animals are also
known, die within in an infected area in just two weeks.
"Where
it has hit, it has been pretty lethal," said Raimondi, a
professor in the Department of Ecology and Evolutionary Biology at UC
Santa Cruz. "This is going on up and down the coast. ... It's
going to change what's out there pretty fundamentally."
Syndrome
discovered
The
disease, which has been dubbed sea star wasting disease, was first
detected last summer in tide pool areas along the coast of Monterey.
Raimondi, who teaches a class in kelp forest ecology, soon began
noticing dead and dying starfish further underwater during dives with
his students.
Researchers
in Sonoma County and in Washington state also detected the syndrome,
which causes the starfish to become mushy and deteriorate until body
parts begin falling off.
Raimondi
said there seems to be a progression, or sequence, of infection in
which different starfish species get the disease at different times.
The
Ochre star, the purple or orange starfish most commonly seen in
intertidal regions, is typically the first to get hit, he said.
"It's
dying in huge numbers," Raimondi said of the species. "We've
seen them go from a lot to zero fast."
The
disease has spread from the shoreline into deeper water, ravaging the
population of sunflower stars, the largest sea stars in the world.
Short spined sea stars and giant sea stars have also been hit hard.
"The
ones that get it first are all predators," Raimondi said of the
starfish, which have very few predators and feed on a variety of
invertebrates, including mussels, sea urchins, clams and snails.
Monterey
Aquarium hit
The
disease has even found its way through the filtration system of the
Monterey Bay Aquarium, which uses sea water in its tanks. Michael
Murray, the director of veterinary services, said the aquarium
carefully controls temperatures and other factors like salinity, but
cannot keep out natural impurities.
"There
is something going on in the water," Murray said.
"Unfortunately, we're not really sure what it is, so we really
don't have the ability to say what it isn't."
Raimondi
said he believes the starfish are succumbing mainly to a secondary
bacterial infection caused by the disease, which spreads in the water
almost like the common cold among the dense, often interwoven,
populations of starfish.
UC
Santa Cruz biologists are collecting samples up and down the coast
from Washington to California while scientists from Western
Washington, Cornell and Brown universities are trying to isolate the
pathogen in the laboratory. They
are looking for marine biotoxins and viruses and exploring a variety
of possible sources, including radiation from the debris that washed
across the Pacific Ocean after the Fukushima disaster.
"We're
not throwing anything out yet," Raimondi said.
Ecological
impact
Although
he doubts it will result in extinctions, Raimondi said the loss of so
many starfish could have serious consequences as mussels and other
starfish prey begin to overpopulate areas where their numbers were
once controlled. As a result, he said, fish, invertebrates, crabs and
other species that feed on algae, plants and other sea life that
thrive when starfish are in control will be marginalized and forced
to look elsewhere for food.
"It
just started, so we don't know yet what it is going to do,"
Raimondi said. "The theory is that there is going to be a
fundamental shift" in the balance of sea life.
Starfish
die-offs have occurred in the past, but Raimondi said they have been
localized and clearly associated with specific events, like a sewage
spill or a sudden influx of warm water. The last substantial sea star
die-off occurred during the 1998 El NiƱo weather pattern, but that
was restricted to Southern California.
It
isn't the only weird thing to happen of late along the California
coast. Marine scientists have been trying to find out why previously
unknown blooms of toxic algae are suddenly proliferating along the
coast. The mysterious blooms, including deadly red tides, have been
bigger, occurred more frequently and killed more wildlife than in the
past.
Last
year at about this time, legions of big predatory Humboldt squid
gathered along the Northern California coast and stranded themselves
on Santa Cruz beaches, far north of their normal habitat.
Other
wildlife healthy
By
most accounts, though, the California ocean ecosystem has been
healthy. Herring were abundant in San Francisco Bay last year, and
there are plenty of salmon off the coast. Harbor porpoises,
bottlenose dolphins and orcas have returned to the region in larger
numbers than anyone can remember, while humpback and other whale
migrations have been growing.
The
strangest thing about the starfish die-off is that it is happening at
a time when ocean temperatures along the West Coast are going through
an extended cool period, something normally associated with ocean
abundance. So far, Raimondi said, there are no signs that the
mysterious killer is slowing down.
"Usually
it is pretty obvious what is causing it. None of those factors
exist," he said. "I don't think it's the end. We see it in
more and more sites."
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