As
he walked on a beach in the western Prince William Sound town of Whittier,
seabird biologist David Irons was startled when he saw hundreds of white lumps
on the black rock beach.
They
were dead seabirds, in what he would discover were likely record numbers, a
sign the ecosystem was being troubled by abnormally warm ocean water.
The
dead birds, common murres that had starved, were lined up and left where the
tide had dropped them on the shore.
"We
have never found close to 8,000 birds on a 1-mile long beach before,"
Irons said of his early January discovery. "It is an order of magnitude
larger than any records that I am aware of."
Biologists
like Tamara Zeller have been boating around Prince William Sound scanning the
beaches for dead and sickly murres. They also count the birds floating in the
water, she told CNN affiliate KTVA.
They
cannot stop at every beach so they estimate the disturbing total of birds from
the ship. When they are able to get to shore, the toll is always much higher.
At
Whittier, one day about two weeks ago, she counted 98 of the black and white
birds while on the water. On shore she saw 284. The day's total for January 7
was 3,000.
Heather
Renner, a supervisory biologist at the Alaska Maritime National Wildlife
Refuge, said the Whittier die-off is part of a much larger event that started
in August.
Renner
estimates that 100,000 common murres have died.
"It's
hard to know how many birds have died because Alaska is so big, and there are
so many remote areas," Renner said.
The
vast majority of the bird deaths are due to starvation. Tests on 100 carcasses
revealed almost all the murres were emaciated, and the culprit is likely their
lack of a good food supply.
"The
fish that they eat tend to have a narrow band of water temperatures they can
live in," Irons said. "If the temperature gets too warm or too cold
the fish disappear."
And
there's plenty of warm water off Alaska's coast right now. Since 2013, an
expanse of seawater that's 2 to 7 degrees Fahrenheit above average has
stretched from Asia to North America. Scientists have dubbed it "the
blob," and they're studying it closely for its effect on wildlife.
According
to the U.S. Fish & Wildlife Service, murres usually spend
the winter offshore, diving into the water for fish, crustaceans and mollusks.
The average adult murre weighs 2 pounds and eats up to 30% of its body weight
per day.
They
typically dive as deep as 250 feet, but if they need to, almost 600 feet is
possible. Their short wings make them excellent swimmers.
The
8,000 dead common murres that Irons observed doesn't put a dent in the overall
population. Neither does Renner's estimation of 100,000 bird deaths.
There are
approximately 2.8 million murres in Alaska.
Their
deaths give clues to a larger picture, Irons said.
"Seabird
biologists say seabirds are indicators of the health of the ecosystem. Now
they're dying and that is telling us something. We should be aware of that. If
we don't record they're dying it goes unnoticed," Irons told KTVA.
The
scientists also say that die-offs aren't uncommon. One in 1993 was estimated at
100,000 murres. There was one in 1997 -- during an El Niño -- that affected
several types of birds. At that time scientists also focused on warm water and
the lack of food.
And
almost 190,000 murres perished after the Exxon Valdez crashed in the sound in
1989, spilling more than 1 million gallons of oil.
But
Irons and Renner say this die-off is different in its scope and the persistence
of the warm water blob that may have caused it.
"Scientists
tend to get blasé about (die-offs) but this is bigger than I've ever seen,"
Irons told KTVA.
Renner
agreed.
"This
is probably one of the larger events and going over a longer period of time and
a bigger geographical area," Renner said.
Murres
aren't just being found on shorelines. They also have been picked up as far
inland as Denali State Park, CNN affiliate KTUU reported.
Being
on land means trouble for murres, whose bodies are designed to take off from
water. The inland murres are grounded and needed to be taken back to the ocean.
Before that they are taken to a rehab facility.
At
the Bird Treatment and Learning Center in Anchorage, staffers usually see a few
sick or starving murres each year. So far this season more than 225 have been brought in.
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