AIRPORT OWLS. Where man sees tarmac and terminals, arctic birds see tundra and home

THERE is a paradox at Logan Airport. One of the busiest places in Boston is also one of the most isolated. In a place that thousands of people fly in and out of every day, few are allowed to even walk outside. Opposite Boston's jagged city skyline and crowded streets is a vast tract of land. To airline passengers and ground-crew workers, the open part of the airport's 1,800 acres may only look like a landing field. To a snowy owl, however, it looks like home.

From November to May each year, snowy owls migrate from their tundra habitats in Greenland, northern Canada, and Alaska to sit out the Arctic winter. Some of the owls go as far south as Long Island and North Carolina, even as far as Bermuda, says Norman Smith of the Massachusetts Audubon Society. And some come to Boston's airport, the 10th busiest in the United States.

To the owls, the airport ``looks more like the tundra than anywhere else in the area,'' says Mr. Smith. Large populations of rats, ducks, muskrats, skunks, and sea gulls make it a five-star winter vacation spot for the owls.

More snowy owls congregate at the airport during the winter and early spring than anywhere else in Massachusetts. Audubon researcher Smith has banded more than 35 this year. The sight of wild Arctic birds sitting amid trash, close-cut grass, radar equipment, and runways has a surreal quality to it, but the airport is a safe haven for these birds. Surrounded by water on three sides, the landing field is off limits to all but a few workers. State Police patrol it around the clock.

Even the airport's ``birdmen,'' whose job it is to keep flocks of birds off the runways, have a special affection for the snowy owls. ``They're funny,'' says Logan Airport worker Pat Giovino. ``No man on the face of this earth knows what they gonna do.''

In the past, airport workers have tried to relocate the owls, because they were concerned that the birds might interfere with air traffic. The owls were trapped and removed several times, but kept coming back. Smith was instrumental in persuading airport officials to let the owls remain. ``Owls have been hit by planes,'' he concedes, ``but they keep larger flocks of birds off of the runways.''

Smith is the sole snowy owl researcher for the airport, in conjunction with his work at the Blue Hills Trailside Museum in Milton, Mass. The airport is ideal for Smith's research, because of the restricted access.

Every weekend since 1981, he has carried out a research routine that includes counting, trapping, weighing, measuring, collecting lice from, and banding owls. Numbers on the metal bands are fed into US Fish and Wildlife Service computers in Washington, along with information about the capture site. Owls that Smith has banded at Logan have been found in Toronto, Manitoba, and even on Hudson Bay.

His assistants, Danielle and Joshua, help in the collection of owl pellets. At ages 7 and 4, respectively, Smith's two children are probably two of the youngest field researchers around.

Snowy owls usually swallow their prey whole. The oblong pellets that result from this feeding behavior are not feces, but indigestible hair, feathers, and bones regurgitated about once a day. Pellets provide valuable information on what the owls eat. When Smith sends the unsqueamish kids out to collect pellets from empty roosts, one can't help thinking of childhood Easter egg hunts.

What Danielle likes most about working with the owls is getting to hold them. Before the birds can be held, however, they must be caught. Smith's trapping technique is a lot like fishing. He even uses a fishing pole and reel to trip the bow trap he sets.

On a recent day, Smith set the trap several times without success, but decided to try one last time. Before he and his young assistants had even gotten settled into their truck, 200 feet away, a small white shape on the crest of a hill unfurled into a winged projectile. It covered the distance from hill to bait in a manner better described as a line drive than a swoop.

Smith left a 10-foot tire patch on the grass as he sped toward the netted bird. ``This is the most immaculate white male I've ever seen,'' he commented, once the bird was safely in hand. After measuring and weighing the bird, and taking photographs, Smith released the owl back into the air, where it was swept up and away by a strong gust of wind.