Four people trudged through muddy tundra in hip waders as a chilly wind beat their rain gear. When the wind and rain died down, mosquitoes mobbed any exposed skin.
Most humans might find this environment uncomfortable. But for the migratory birds that travel thousands of miles each year to lay their eggs here, it's ideal.
“There are so many shorebirds that come to Kotzebue, it's a really productive area,” said Rozy Bathrick, a PHD student studying the birds’ migrations. “The wet tundra is just an excellent habitat for them. Mud flats are some of their favorite habitat to forage in.”
Bathrick, along with two assistants, is studying shorebirds throughout the state, from Bethel to the small Cook Inlet community of Beluga. It's part of a collaboration with the U.S. Fish and Wildlife Service and the United States Geological Survey.
The team is in Kotzebue — the last stop on a month-long research trip — to find the long-billed dowitcher.
Bathrick said the dowitchers have nearly a thousand mile-nesting range, from the Y-K Delta to Utqiaġvik. Kotzebue is of particular interest to the researchers because it hosts two distinct bird populations. Bathrick says little is known about the groups.
According to Bathrick, some of Kotzebue’s dowitchers will travel more than four thousand miles to the Gulf of Mexico in the colder months, while others migrate straight down the Pacific Coast to Southern California.
While many shorebirds are hard to identify, the long-billed dowitcher has some unique characteristics that make it easier. About the size of a robin, the dowitcher has a long beak about three times the size of its head, which it uses to search for insects. The birds have colorful rust colored feathers on their chests during the summertime. Juvenile and non-breeding dowitchers have grayish colors.
“Usually when they're foraging, they just plant [their beak] deep in the mud,” Bathrick said. “Then they move it like a sewing machine needle just kind of up and down.”
Bathrick’s team searched for the birds in a boggy area outside of town, near solar farms.
“We had this hypothesis that birds liked that area, because unlike other parts in the open tundra, there's actually cover there under solar panels,” Bathrick said.
It was relatively quiet at the site, so the team split up. Suddenly, while looking for berry patches near the solar panels, a dowitcher flew by.
Bathrick’s team sprang into action, setting up a nearly 40-foot-wide net. Then Bathrick played the sound of a dowitcher chick in distress on a portable radio, to lure the bird in.
“The birds have this spike in hormones right now and they're really reactive to sounds like that,” Bathrick said.
Instantly, the bird emerged from tall grass and flew straight toward the net. After trapping the bird, Bathrick untangled it and held it in her hands.
The team took a series of measurements, including weight, body lengths, feather and blood samples.
One of the last steps is attaching a tag and small GPS locator, close to the dowitcher’s hip joints. This allows the researchers to track the bird as it makes its southern migration. As Bathrick released it, it flew toward another bird that also had a GPS locator attached — possibly the bird’s mate, the researchers think.
Bathrick said tracking the birds can help pinpoint critical areas where the birds stop along their route to refuel, or where they might be dying — which is important because shorebird populations have declined steeply in recent years.
According to Bathrick, while dowitcher populations are declining across their entire range, they’re most at risk of dying during their migration and in their winter habitat. The shorebirds are relatively safe on the tundra during their breeding season. But that habitat could be in danger as warmer Arctic temperatures and increased vegetation could dry out the summer nesting grounds.
“There's climate change that's impacting these landscapes, the shrubification is changing their breeding habitat, they really rely on open wet areas to breed in,” Bathrick said.
Researchers plan to turn on the tracking equipment later this month, before the birds fly south for the winter.
