FW Article: Owl patrol

Kevin Li kdli at msn.com
Mon Mar 11 19:36:14 PST 2002



>From the Christian Science monitor, an article on snowy and saw-whet owls.


Kevin Li
kdli at msn.com
Ballard, USA

The Home Forum > Kidspace
from the March 12, 2002 edition

Owl patrol

Arctic snowy owls searching for a homey spot head for ... Boston's airport?

By Samar Farah

If Norman Smith has some spare time, he likes to spend it at the airport.
He's not watching airplanes, though. He's watching owls.
The director of the Massachusetts Audubon Society's Blue Hills Trailside
Museum in Milton, Mass., has special permission to patrol Boston's Logan
International Airport. He drives his pickup near the runways, looking for
snowy owls.

Mr. Smith has been peering up at the sky for as long as he can remember,
straining to spot hawks and owls in flight. He's always had a special
feeling for "snowies," as he calls them. The large, mostly white nocturnal
birds spend most of their time in the far North.

But it's not just snowies' charm that has Smith hunkered down in his truck
for hours at a time, watching owls amid the screaming jetliners. What
fascinates Smith is all that's left to learn about the owls. It's the
"mystique of this white creature," he says, that attracts him most.

For example, scientists know that snowy owls have four talons on each foot,
instead of the usual three. They know snowies can live up to 10 years in
captivity. But no one can even estimate a snowy's lifespan in the wild.
Researchers know the owls live mostly above the Arctic Circle, but no one
knows where, in particular, they congregate. The owls' migration habits are
largely unknown, too.

Naturalists do know why snowies like Boston's airport, though. And that's
where Smith comes in.

It began in 1981, when Smith got a call from the United States Fish and
Wildlife Service. Could he help them trap a snowy owl living at Logan?

The owl was a hazard to planes taking off and landing. Birds, especially big
birds (snowy owls can be two feet tall with wingspans of 5-1/2 feet), may be
accidentally sucked into jet engines. This can severely damage the engine
and even cause the airplane to crash.

Keeping birds away

A rotating three-person Bird Patrol, hired by the airport, does everything
it can to reduce the bird population there. They have lots of ways to do
this, including the use of "cracker shells" and propane cannons. These are
big noisemakers intended to scare off the birds without hurting them. As a
last resort, the Bird Patrol may shoot particularly large and persistent
birds, such as sea gulls and crows. The Migratory Bird Treaty Act prevents
them from shooting snowies, though. Instead, they call Smith.

Smith successfully trapped that first owl in 1981. Since then, he's been
trekking to the airport at sunrise and sunset several times a week, pursuing
the mystery of the snowies. He's trapped nearly 300 snowy owls to date.
Logan airport, in fact, is the best place to find snowy owls around here.
(You're not likely to spot the airport owls yourself without binoculars.)

The owls' natural habitat is the Arctic tundra, treeless stretches of open
grass. But every year, from November to April, when many birds fly south,
snowies can be found almost anywhere on the airport's 2,400 acres: on the
edge of the parking garage, by runways, even perched on control towers
bristling with spikes designed to keep all birds off.

Why do snowy owls like it here? The wide-open spaces and low-cut grass make
it seem like home. Their favorite meal - a small rodent called a lemming -
doesn't live anywhere near Boston. But the owls find plenty of other small
rodents, namely meadow voles (a cousin to the lemming) and urban rats.

Not even the thunder of 1,000 planes taking off and landing daily deters the
owls. While they do have extremely sensitive ears, Smith says they must get
used to the noise the same way people learn to ignore traffic noise in the
city. Smith fondly recalls observing one particular owl that catnapped all
day in the middle of the airfield, completely unfazed by planes passing
overhead. (Smith wears earplugs at the airport most of the time.)

Letting the grass grow longer at Logan might keep away a few snowies. But
Smith says that nothing - not even paving the airfield completely - would
make this or any airport completely bird-free.

That's why Smith is good to have on hand. He drives around the airfield in
his pickup until he spots an owl. Then he'll park and set up his trap about
100 feet away. He uses a live mouse in a wire cage to lure the owl into the
trap. A long string runs from the trap to his truck.

When the owl approaches the trap, Smith pulls the string, which flips a net
over the owl. Just this year he's caught 22 different snowies.

He takes every owl back to the bird sanctuary in the Blue Hills, near
Boston. There, he "bands" the owls, placing a numbered aluminum strip around
the owl's ankle. That's so the owl can be identified later. Then he lets the
owls go.

Two of this year's owls have also been fitted with small satellite
transmitters. This is part of the Trailside Museum's new program to study
the snowy's migration patterns. Where do the owls go, for example, when
they're not at Logan?

Keeping tabs by satellite

A Teflon-coated harness attaches the transmitters to the owls like a
backpack. The radios are very light - 30 grams, or about one ounce. (Male
snowies weigh from three to four pounds. The usually larger females are
between four and five pounds.) The harness is held on with dental floss.
When the floss deteriorates in two years, the transmitter falls off. Two
years is about the length of time the transmitter's batteries last.

Smith says the bird is hardly aware of the transmitter. The snowy eventually
preens its feathers in such a way that only the radio's antenna is visible
on its back. It transmits signals via satellite to a firm in New Jersey,
which then determines the owl's exact location.

As long as the transmitter is attached and the battery is running,
scientists can tell the bird's location and whether it's moving or
stationary.

The Snowy Owl Telemetry Research Project is now in its third year. In two
years, researchers have learned more about snowy owls' migration than they
had in the past 20 years, Smith says. Some of the owls have returned briefly
to Logan Airport; others have been tracked as far north as Baffin Island in
Canada.

"The longer we work on this," Smith says, "the more questions we have." And
the answers to some of these mysteries may lie no farther than one's
backyard - or the nearest airport. All you need is a careful eye.

People sometimes ask Smith how he can tell one snowy from the other. It's
the same as with people, he says: "Every single one is different," They may
not be much to look at during the day, when they resemble nothing more than
"big, fluffy white mounds." But at night, when they are most active,
"they're spectacular."

A high-schooler finds owls that others had overlooked

Norman Smith has been bringing his two children on snowy owl expeditions to
Boston's Logan International Airport since they were 2. But he's the first
to admit that he's learned something about owls from them. In fact, not only
Smith but also other owl researchers have learned a lot about owls from his
oldest daughter's high-school science project.

In 1994, Danielle Smith, then a freshman, entered the Massachusetts State
Science Fair. Danielle wanted to study how weather conditions affect the
migration of saw-whet owls, small owls that average 7-3/4 in. tall and
populate wooded areas in the Northeastern and Western United States. She
proposed the nearby 476-acre Daniel Webster Wildlife Sanctuary as a research
site. But her father and others discouraged her, pointing out that saw-whets
had never been spotted there before.

Danielle persisted, however. "She had a hunch," her father says. But more
important, she's always had a "wondering and questioning" mind.

Eventually, Mr. Smith relented, and he and Danielle set up a large mesh net
in the woods that September. By the end of November, they had caught,
banded, and released 10 saw-whet owls. Encouraged, they repeated the
experiment the next year. Their results more than quadrupled: They caught 53
saw-whets. In 1999, they brought the project to their backyard in Whitman,
Mass., about 20 miles southeast of Boston.

Danielle describes her backyard as small and almost treeless. Nevertheless,
she and her father caught 36 owls that year in a trap they set up by their
pool. Apparently, saw-whets pass through Greater Boston on their migratory
route. They are so small, they had previously been undetected.

The project continues today. In all, Danielle and her father have trapped
and banded 722 saw-whets. And the Massachusetts science fair? Danielle won
second prize. But more important, she has shared her findings with other owl
researchers in the Eastern United States.





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