Biologists turn Maine island into a tern haven
OUTER GREEN ISLAND, Maine --After three months spent crouching in a box, flapping her arms, and wearing a crude cardboard hat, Julie Hart is about to close the book on one of the summer's strangest scientific success stories: the creation of a safe haven for the endangered roseate tern.
For the first time in more than 90 years, roseate terns graceful, seagull-like birds that once nested up and down the New England coast have returned to this island to raise their chicks. Outer Green Island was once a vibrant colony of terns, until they were killed off for their eggs and feathers, used to decorate fashionable ladies' hats.
Hart, an Audubon-funded researcher, moved here in May and has spent the last three months frightening off seagulls, falcons, and the other predators that took over the island decades ago. She has gotten boils from poisonous plants and been pecked on the head by the terns themselves all to help the birds establish a hold, however tenuous, on the island.
"We want them all to make it," said Hart, "and we know very few of them will."
Hart is one of a few hundred ecologists around the world who dedicate months of their lives to lonely campaigns to build new colonies of threatened or displaced migratory birds. In California, the Common Murre Restoration Project is attracting murres back to Devil's Slide Rock off San Francisco after they were wiped out by an oil spill in 1986. In Japan, biologists are trying to move a colony of rare short-tailed albatross away from their home on an active volcano.
These projects are based on an idea called "social attraction," which amounts to a kind of bird psychology. Developed by a biologist named Stephen Kress, it uses decoys, recordings, mirrors, and even fake eggs to trick birds into thinking they are joining a thriving colony. Kress first used the approach in 1973 to restore puffins to Eastern Egg Rock in Maine. Since then it has been used to relocate nearly 40 species of birds in 12 countries.
"Before that, no one had even thought you could start a seabird colony," said Kress, now director of the National Audubon Society's Seabird Restoration Program, which manages Outer Green Island and six similar projects off the Maine coast.
When it works, the approach can ensure survival where there would have been extinction, but the payoff can be achingly slow. This is the tern project's third year on Outer Green Island, and so far only 13 pairs of roseate terns have nested here. Their more populous (and nonendangered) cousins, the common terns, returned to the island in the summer of 2002 and have now built 700 nests. Still, the colony isn't ready to try surviving on its own; just Tuesday, two fledging terns fell from a 50-foot cliff and drowned, and a seagull flew off with another tern in its bill.
The technique requires a certain kind of dedication, often from young field biologists like Hart, a 25-year-old with a degree in environmental science from the University of Vermont. This summer she has done without plumbing, refrigerated food, and any number of personal conveniences. She has not had a shower since a boat ferried her to the mainland for a few hours at the end of June.
"This kind of person there are many of them out there," said Kress of Hart and the conservationists working on the other Maine islands. "They don't want to come off the islands during the summer."
This is Hart's first year on Outer Green Island, a rocky outpost so small she can walk its length in five minutes. She rises to count the birds at 6 a.m., checks on the nests, and takes two "gull walks" a day, jumping and screaming at any seagulls lingering on the rocky shore. Hart is careful to avoid the oil of the cow parsnip plant that gave her painful boils in June, and to sweep away the profuse but harmless spiders that weave webs on the paths.
Food arrives once a week on a boat, which Hart meets by rowing out in an inflatable dinghy. The riptides and rocky shore make swimming a dangerous proposition, but Hart manages an occasional cold-water bath.
There is also a rotating pool of nine volunteers and interns, each of whom spent a week on the island with Hart. Currently the volunteer is Suzann Regetz, 30, a legal secretary and bird enthusiast who is considering a new career in field biology.
Hart and Regetz spend six hours a day sitting in blinds wooden boxes perched on the island's rocks, just large enough to crouch in so they can observe bird life unnoticed. They record what fish the terns bring in and which bird of each pair watches the nest while the other forages.
When Hart approaches the tern colony nesting on one edge of the island, she encounters the terns' famous family instinct. They are fiercely protective of their young and dive-bomb anyone who enters their colony. While Hart tags fledgling terns, Regetz stands on higher ground to distract the adults. She wears a kind of headgear peculiar to bird researchers: a hat with a stick and a piece of cardboard designed to keep the birds from pecking her head.
At quieter times, inside the blind, Hart can see the rewards of her work in the slow drama of a new colony establishing itself. When newborn terns hatch, they appear as fragile puffs peeking out of crevices, unable even to regulate their own temperature. Adult terns occasionally sit on newborns to keep them warm a technique called "brooding" while the other parent provides a constant stream of food.
After counting, banding, and screaming at gulls, Hart and Regetz go home each night to two tents pitched near a cabin with solar panels, a laptop computer, a tool kit, and water.
Nesting season ends next week, and Hart leaves the island on Aug. 10. The terns will migrate to Argentina or Brazil until they come back next year. Hart doesn't know if she'll be returning with them, but for now she has her mind on something more immediate: An intern brought her a pint of strawberry Ben & Jerry's earlier this summer, and she has been thinking about ice cream ever since.
Jessica T. Lee can be reached at jtlee@globe.com.
