http://seattlepi.nwsource.com/local/264581_deadbirds28.html
Tuesday, March 28, 2006
Razor-thin birds wash up on shore
Hundreds of dead auklets found on Oregon coast
By ROBERT McCLURE
P-I REPORTER
Once again, things are starting to look weird along the West Coast.
A rash of bird deaths has scientists wondering if they're seeing a
repeat of last year, when they were alarmed by throngs of dead birds
washing up on beaches, underfed whales and the failure of Washington's
largest seabird-nesting colony, among other developments.
Like last year, scientists say, this year's bird deaths appear related
to changes in the marine food web that they still don't understand but
that look as if they are related to unusual weather.
The dead birds are being tested for toxins, bird flu and other
diseases. But many are so scrawny that researchers say it's virtually a
foregone conclusion that they starved to death.
"You've got skin and little more over the breastbone," said Bob
Loeffel, a biologist who has scoured one stretch of Oregon beach for 28
years. "They're thin. Razor-thin."
Dead birds have been turning up along the Pacific coast from the
Columbia River south to about Newport, Ore., and in British Columbia.
The birds dying in unusually high numbers in Oregon are rhinoceros
auklets, a fish-eating bird a little smaller than a crow. Before this
year, Loeffel had never found more than 13 of them in March on the
4.6-mile stretch of beach he monitors. This year it will easily exceed
100, he said. His is the longest-running study of dead birds on the
Northwest coast.
Hundreds of other auklets have been found up and down the Oregon coast.
"We've seen a dramatic rise in the number of rhino auklets washing up
on the beaches," said Julia Parrish, a University of Washington
professor who oversees a network of Northwest beach observers called
the Coastal Observation and Seabird Survey Team. "One thing that's
given us pause is waiting to see if this is a several-week event, or is
this going to go on longer?"
For now, she said, it appears restricted in the United States to the
Oregon coast.
In Canada, the confirmed deaths have been among Cassin's auklets, and
they mostly occurred from late December to early February. It's not
uncommon for juveniles to die, but this time adults were found dead.
"We believe they starved to death, but we really don't know the
linkages here, whether it's related to what we saw last summer," said
Robert Elner, chief of migratory bird conservation for the Canadian
Wildlife Service. "There's something happening. ... We've got signals
that there's something amiss."
Researchers are convinced that much of what they saw in 2005 was
related to an interruption of the normal spring weather patterns, with
overly warm, nutrition-poor ocean water hanging around when cold,
food-filled ocean water normally moves in. They say it's easy to see
why that happened: Wind that usually kicks up this time of year failed
to do so.
But they don't know why the wind didn't blow.
Could this year's wave of deaths be bird flu? Lab tests could show
that, but "it's highly, highly unlikely," said the UW's Parrish.
Cassin's auklets begin to congregate along the coast in preparation for
breeding early in the year, before the rhino auklets, Parrish said.
Then, in March, the rhino auklets do the same thing. It's usual to see
some of them die, but perhaps 10 times as many as normal are washing up
this year.
"It seems like some combination of weather and local food shortage,"
she said. "That is potentially why whatever happened didn't affect
other species: They weren't here."
One possibility is that the birds didn't get as much food as normal
last summer, then had to weather a relatively cold and rainy winter and
died because their fat reserves were exhausted earlier than usual,
Parrish said.
There are some reasons to think that this year will be better. For
instance, in the Farallon Islands off San Francisco, where birds showed
up late to breed in 2005 and later abandoned their nests, they seem to
be back to their normal pattern, Parrish said.
Dave Mackas, a biologist with the Canadian Department of Fisheries and
Oceans, noted that the warmer-than-usual ocean conditions started
around 2002 and appeared to peak last year. The Oregon coast and ocean
were hardest hit, with lesser effects stretching to the north and
south, he said.
"My bet is 2006 won't be as bad as 2005," Mackas said. "But it doesn't
mean we won't see another 2005 down the line if the ocean gets warmer."
WEIRD WEATHER
With ocean temperatures warming to unusually high levels over the past
three years, scientists noted a string of odd happenings affecting
marine life from northern California to Alaska.
Here is what has happened this year:
British Columbia coast: Cassin's auklets washed up dead.
Oregon coast: Rhinoceros auklets washed up dead from the Columbia River
to Newport.
Whidbey Island: A Humboldt squid, normally found in Mexico and Southern
California, turned up on the beach on Jan. 2.
What happened in 2004-2005:
Triangle Island: Nesting success plummeted for the Cassin's auklet.
Lake Washington and Ship Canal: About half the 2004 run of sockeye
salmon -- some 200,000 fish -- failed to materialize. Scientists
suspect overly warm water was the cause.
Protection Island: Last summer, glaucous-winged gulls that normally
fledge about 8,000 chicks produced only 88.
Tatoosh Island: Breeding started late for common murres last spring.
Only about one-fifth fledged chicks, compared with up to four-fifths in
a good year.
Northwest coast: Tens of thousands of common murres and Brandt's
cormorants -- emaciated at a time of year they should be flush --
turned up dead on Oregon and Washington beaches in spring 2005.
Southern Washington to Alaska Panhandle: Numerous sightings of Humbolt
squid, which normally live off Southern California and farther south,
in October 2004.
Northwest coast: Gray whales migrating from Mexico to the Bering Sea
had so exhausted their fat reserves that their bodies were misshapen as
they passed by last spring.
Northwest coast: Scientists trawling for young salmon found counts
extremely low in spring and fall 2005.
Northern California: Scientists trawling for young rock- fish found
counts very low in 2005.
Farallon Islands: Auklets abandoned their nests in unprecedented
numbers. Where hundreds of chicks normally are produced, only a handful
were in 2005. Lack of food is blamed.
Monterey, Calif.: Large number of seabirds found dead on beaches in
spring 2005.
--------------------------------------------
Birding-Aus is on the Web at
www.birding-aus.org
birding-aus.blogspot.com
--------------------------------------------
To unsubscribe from this mailing list, send the message:
'unsubscribe birding-aus' (no quotes, no Subject line)
to
|
