THE VIRGINIAN-PILOT Copyright (c) 1995, Landmark Communications, Inc. DATE: Monday, July 10, 1995 TAG: 9507100100 SECTION: FRONT PAGE: A1 EDITION: FINAL SOURCE: BY LANE DEGREGORY, STAFF WRITER DATELINE: PUNGO LAKE, N.C. LENGTH: Long : 108 lines
The widow Abigail completed her annual 3,300-mile flight alone this year.
With a candy-bar-size satellite transmitter strapped on her back between her wide, white wings, the 15-pound tundra swan arrived at the Arctic Circle on July 1 after a three-month journey.
She soared from Pungo Lake in rural North Carolina, along the Chesapeake Bay, through the Appalachian Mountains, over the Great Lakes, and across hundreds of miles of lonely Canadian land before landing in fields of wild grain in the Northwest Territories, near the Mackenzie River.
By the time she finished her journey, she'd flown through at least a half-dozen military restricted flight areas. A trio of biologists tracked her every move with electronic equipment orbiting high in the atmosphere.
Their mappings will help military officials keep $20 million aircraft from colliding with migratory waterfowl.
``Most cockpits are built to withstand strikes from 5-pound birds,'' said biologist Adam Kelly, a civilian Air Force contractor who helped tag and track Abigail. ``Swans can weigh 15 to 20 pounds each. Whenyou're flying at 400 knots, if a bird like that hits you, you won't survive.''
``We wanted to know how swans leave this area, where they go when they head north each spring,'' he said, standing outside his trailer on the Air Force Bombing Range, between Stumpy Point and Englehard.
``Tundra swans fly through the bombing range in such huge numbers, we wanted to track their paths to fill in the big picture for the military,'' he said.
Based on Abigail's travel, Kelly said, planes from Oceana in Virginia Beach are right in the swans' path when they come into the Dare County ranges. ``Those pilots could easily collide with waterfowl on the way,'' he said. ``We want to extend our model to help warn planes coming out of Tidewater.''
Kelly and two colleagues are conducting a two-year study of birds at the North Carolina bombing range. They plan to produce a ``Bird Avoidance Model'' that will show pilots how to keep out of most species' flight paths. Each year, military experts estimate, about 3,000 U.S. Air Force planes collide with birds.
At least one pilot has died since 1993 and another has been permanently injured as a result of bird strikes.
``Swans fly at heights between 500 and 1,000 feet - the same altitude as many military aircraft,'' Kelly said, as an A-10 jet sliced the sky overhead. ``Historically, we haven't had many bird strikes with swans. But as their numbers increase, it could become a catastrophic problem for pilots.''
About 40,000 tundra swans winter around southeastern Virginia and northeastern North Carolina. They fly north to Alaska and northern Canada for summer.
And in recent decades, Kelly said, their numbers have been increasing.
Tundra swans live about 20 years and usually mate for life. They hatch three or four babies each year and can fly up to 600 miles in a single day. Their long necks, Kelly said, enable them to eat grasses and reeds in shallow lakes.
Abigail, a 3-year-old female with a 7-foot wingspan, long, black beak and small, yellow patches on the bridge of her nose, was selected from 30 swans to wear the $3,000 satellite transmitter backpack that the Air Force supplied in February.
To catch her, biologists set up a 100- by 60-foot net and baited it with corn. ``Abigail was the biggest, strongest bird we trapped,'' Kelly said. ``A real super swan. That's why we chose her to wear the transmitter.''
The harness that straps the transmitter to her back was specially designed to ensure it wouldn't affect her flying, which reaches speeds up to 30 miles per hour.
Scientists think Abigail's mate probably died last winter, because she stayed south with juvenile swans several weeks after her peers had flown the coop. Single swans are not in a hurry to get to their summer homes because they won't have any eggs to lay.
She left Pungo Lake on April 3 and stopped just below the Arctic Cirle nine days ago. Abigail is the first bird the biologists know of that has been tracked all the way from winter to summer feeding spots. Every three days, Kelly and his crew got a fix on their swan.
``She only transmitted for six hours every three days because we're trying to make the $100 battery last until the swan returns,'' he said. They tracked her journey on the 5-foot-long color map tacked to the wall of his trailer, affixing another paper swan cutout after each transmission.
The swan flew almost due northwest after leaving the United States. But her path was more indirect from North Carolina through Minnesota.
Instead of crossing the Great Lakes in a single swoop above open water, Abigail made smaller trips over the lakes' southern tips, where land offered regular stop-over spots.
Besides recording geographical locations, Abigail's water-and-peck-proof transmitter shows scientists how high she is flying. An altimeter attached to her harness measures barometric pressure at the swan's altitude. The entire experiment is costing taxpayers about $6,000.
By October, the swan probably will have begun her journey south.
``We want to see if she retraces her steps on the way back or takes a separate route. She'll be young, free and single then - looking for a mate,'' Kelly said. ``As long as someone doesn't shoot her, Abigail should be back here by November.''
If Kelly can recapture Abigail and recover her satellite transmitter, the price of the experiment would be cut in half.
And results for the military could be priceless. ILLUSTRATION: Color U.S. AIR FORCE photo by Christie Atkins
Andreas Smith, one of three biologists on the project, holds Abigail
before she flew north.
Staff Map
Abigail's migration route
by CNB