By DOUG O'HARRA, Anchorage Daily News (Published: April 28, 2003)
Blazing sun, crashing surf and exotic shorebirds on the wing. Days spent hiking
white-sand beaches of deserted Polynesian atolls, partly for a chance to see
Alaska's rare bristle-thighed curlew in its winter home. Does this sound like
an idyllic spring break or what?
Not quite. During a three-week survey last month to islets scattered across about 500 miles of the Tuamotu Archipelago southeast of Tahiti, three Anchorage scientists found themselves seasick, sunburned, scratched from coral, dodging little sharks and exhausted after daylong marches through 100-degree heat."It was far harder field work than anything I've done in the Arctic," said shorebird coordinator Rick Lanctot, with the U.S. Fish and Wildlife Service in Anchorage. And then there were the rats. Little black ones that lurked in the dark."If we used our headlights to shine around us, you could see their eyes," he said. "One time, I counted 20 rats just running around by our campsite. ... In some places, the traps would catch two at a time." But Lanctot, along with biologists Lee Tibbitts and Verena Gill of the U.S. Geological Survey's Alaska Science Center, returned home with new counts of the rare Alaska curlew from these islands, more than 5,000 miles from their only known nesting grounds in upland tundra of the Seward Peninsula and the Nulato Hills. Along the way, the trio also helped document new populations of several critically endangered bird species and the threats they face from rats, feral cats and coconut plantations where undergrowth has been burned away. The research will be used to figure out whether the invasive predators can be eliminated from certain islands and native habitat restored.The worst places were virtually devoid of native birds, presenting a sterile pavement of broken coral under coconut groves."It was so quiet," Gill said. "The only birds (nesting) there were little white terns that nested high up in the trees.""I found it very alarming," Lanctot added.Aside from the bird surveys, the team was laying the groundwork for monitoring and protecting Alaska's bird species during their migratory journeys across the Pacific Ocean and beyond, explained USGS shorebird biologist and curlew researcher Bob Gill. Alaska is one of the hemispheric centers for breeding shorebirds, with at least three dozen species of regular breeders scattering to five continents and Oceania during winter. One of the most intriguing of these is the bristle-thighed curlew, named for the bristlelike feathers on its upper legs. This Alaska-born bird is the only migratory shorebird that winters exclusively on oceanic islands. Gill said it is the only shorebird known to use tools during foraging -- by smashing eggs with little pebbles. Only a handful of other species fly as far nonstop over the open sea, a task that requires each bird to stoke up with so much fat that it shrinks its internal organs.Because there are thought to be fewer than 10,000 of them, including about 7,000 of breeding age, and they seem to be declining for unknown reasons, the species is listed by federal agencies as one that might be in trouble. To figure out why, shorebird specialists need to learn more about what happens to the birds during time they spend away from Alaska, Lanctot said. It's the only shorebird, for instance, that has a flightless molt. That is flightless during molt, when it grows new feathers. What if that leaves them vulnerable to cats and rats on the islands? Hence the trip to the South Seas.Along with scientists from Hawaii, Tahiti, New Zealand and England, the three Alaska biologists flew to an island called Rikitea in early March, then voyaged atoll to atoll in a 49-foot catamaran called Botany Bay. The boat crew included two Alaskans from Cordova and a bona-fide descendent of Fletcher Christian, the English seafarer who led the mutiny on the Bounty and later settled Pitcarin Island.The 14-member team visited 11 atolls over three weeks, some unexamined by scientists in at least 80 years. Aboard they had no refrigeration and no fresh water for bathing and had to share bunk space for 12 in the catamaran's narrow, stifling submarinelike hull. Lanctot and Gill, spouses in civilian life, said it was no romantic South Seas getaway. "Everybody called it the 'pit of despair' because nobody wanted to sleep down there," Gill said. Still, the trip was often exhilarating, especially when they landed on one atoll that had never been developed or cleared by people. There the team counted 500 of the critically endangered Tuamotu sandpipers, possibly doubling the known population in the world. The birds were remarkably unafraid, Lanctot said."But the day after you went there, a pregnant rat could jump off a boat, everything would change," he said.While the Alaskans participated in surveys, they watched for the curlews as well as several other species of Alaska shorebirds. In the end, they counted 268 bristle-thighed curlews, 339 wandering tattlers and 64 Pacific golden plovers.Catching the curlews for blood samples and banding proved difficult, Lanctot said. The birds were seen foraging along lagoons and channels and swooping along the shore. Nets and traps didn't work. They had to run them down.
On one of the last islands, the biologists snatched a curlew that had been scarfing down hermit crabs in the channels between islets. That night, they caught two more using million-watt floodlights that stunned the birds long enough for another person to snatch them, Lanctot said.The trick, it seemed, was targeting curlews that had become positively swollen with winter food."They were really, really fat to the point where they had a hard time flying," Lanctot said. "The birds we caught weighed almost twice as much as the birds we see on the breeding grounds."These birds, on an atoll called Reitoru, were on untouched islets across open water from a developed places. The scientists placed colored bands on their legs, took blood samples and let them go.
Those three birds are almost certainly winging toward Alaska right now, somewhere over the middle of the sea.
