Saw this in a not so local newspaper and thought some people may be
interested:
The Flight of The Albatross
We knew they left their young but not
how far they went
Call it the case of the disappearing albatross.
For years, scientists have been struggling with an
ornithological conundrum: Where do the big marine
birds go when they leave their newly hatched
nestlings on isolated Pacific islands and vanish for
weeks at a time?
Now researchers have an answer: everywhere in
the North Pacific Ocean, including the waters near
San Francisco. Like many visitors to the Bay Area,
they're apparently coming for the food.
``The distances they're traveling is amazing,'' said
David Anderson, a biologist who is tracking the
birds. ``And I don't mean one or two -- I mean all
of them.''
Scientists knew the birds weren't on idle pleasure
flights when they disappeared. That's because they
invariably return to their nests with crops full of
nutrient-rich fish oil, which they regurgitate into
the clamoring maws of their young.
But no one had the the foggiest idea where the
birds were foraging.
Now, thanks to sophisticated tracking devices,
scientists have pinpointed three black-footed
albatross that roamed 2,600 miles from a tiny
Hawaiian atoll to San Francisco.
The resolved mystery may be credited to the
Albatross Project, which is bolstered by a
$200,000 grant from the National Science
Foundation. As part of the project, more than
1,000 schoolchildren are avidly tracking the birds
with the help of microprocessors and satellites.
Anderson, based at Wake Forest University in
North Carolina, employs radio telemetry to track
albatrosses because the birds fly too fast for boats
and too slow for planes.
Radio telemetry involves the use of radio
transmitters fitted to animals to log their
movements and behavior.
While the technology has been around for decades,
transmitters suitable for albatrosses are relatively
new -- especially when coupled with satellite
technology.
``This kind of thing wasn't even possible a few
years ago,'' said Wayne Thompson, a spokesman for
Wake Forest University. ``The transmitters were too
big to use on seabirds. But now we have ones that
are about the size of a dollar bill.''
Thompson said the new transmitters are small
enough to fit unobtrusively between an albatross'
wings, but powerful enough to transmit data to relay
satellites.
On January 22, Anderson and his crew began
taping the transmitters to albatrosses nesting on
Tern Island, an atoll in the Hawaiian chain that
once served as a Coast Guard base. About 3,400
black-footed and Laysan albatrosses nest on the
island. So far, Anderson has fitted 26 birds with
the transmitters.
As the birds wander from Tern Island, their
transmitters beam data to satellites stationed over
the Pacific.
The satellites note the time, latitude and longitude
of each transmitted position. Later, the information
is transmitted to Wake Forest's computer network.
``What's really wonderful about this is that the
schoolkids are actually part of the scientific
process,'' said Anderson. ``They get the same data
we get, and they get it at the same time.
``We're in direct contact with them, and they
participate in our discussions -- there is no
filter. In a very real sense, they are scientists,
not science students.''
Michelle Bergey, a third-grade teacher in
Twentynine Palms, said the project helps her kids
learn about geography, navigation and marine
science, as well as the travel vagaries of ``their''
birds.
``Because it all relates to what their birds are
doing, they stay very involved,'' Bergey said. ``And
some of this stuff is very complex, particularly for
third-graders. But context makes all the
difference.''
Anderson said he was stunned when he began
getting data back from his albatrosses. They were
flying from Alaska to San Francisco, and most points
in between.
``One Laysan albatross,'' he said, ``flew more than
2,000 miles to a specific place on a small island in
the Aleutians, flew back to Tern Island, stayed over
a day, then flew straight back to the same place on
the same Aleutian island.
``Talk about navigational skills -- I can't even
find my way home at night.''
Of the trio of albatrosses in San Francisco, two
appear to be heading back to Tern Island and one
``is still mucking around'' the city, Anderson said.
They may well have come for the calamari.
``Albatrosses are basically scavengers,'' said
Anderson. ``They're especially fond of big squid
die- offs. After squid mate, they usually die en
masse. It can involve thousands and thousands of
individuals. That's a real bonanza for an
albatross.''
Similarly, albatrosses will flock to dead whales and
other sizable chunks of marine carrion.
``We have no way of knowing, but that may be
why they'll return to the same place (such as a
particular Aleutian island) after flying thousands
of miles back to their nests to feed their young,''
said Anderson.
``It's possible they may have located a big carcass.
Or they could also be following boats. Both Laysan
and black-footed albatrosses like to trail fishing
boats, eating the offal that's cast overboard.''
Albatrosses, Anderson says, can fly such long
distances because they aren't really flying --
they're soaring.
``It's called dynamic soaring,'' he said. ``(They
can) go long distances without flapping, because of
a special shoulder joint that locks their wings into
place.''
While albatrosses leave their young for weeks at a
time during their extended explorations of the high
seas, the fledglings are in no danger of starving to
death.
During their long flights, they gorge on fish or
carrion, keeping it in the proventriculus -- the
upper portion of the gut. Here the heavier liquid
elements separate, leaving a large quantity of
fat-rich material. One researcher calls the oily
stuff ``the albatross equivalent of a plutonium
battery -- almost pure energy.''
When an adult returns to its nest, it coughs up the
contents of its proventriculus into the gaping beaks
of its young, providing each nestling with up to 20
percent of its body weight in food.
But as young Tern Island albatrosses eat, so are
they eaten.
``Large numbers of tiger sharks congregate at the
island each year when the fledglings begin flying,''
said Anderson. ``They eat the young birds that fall
into the water. About 10 percent of the fledglings
end up as shark food. The sharks disperse at the end
of the nesting season.''
While the Albatross Project has answered some of the
riddles about albatross behavior, the data are by no
means conclusive. Scientists now generally know
where Tern Island albatrosses go, but it's still not
completely clear why they're going there.
Nor is a troubling trend understood -- a long-term
worldwide decline in albatross populations.
``There are a few theories du jour,'' said Anderson.
``One is that the long-line fishing industry may be
a factor. It could be that the birds are getting
snared in the lines when they attempt to take the
baits. But at this stage, it would be a mistake to
jump to any conclusions.''
Further research will include additional telemetry
work. Anderson is planning to tag Tern Island
albatrosses for at least one more breeding season --
and when he does, thousands of kids across the
country will be avidly awaiting the results.
``As long as they keep e-mailing us the questions,''
he said, ``we'll keep trying to answer them.''
For more information, contact the Albatross
Project at http://www.wfu.edu/albatross
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