Cameras Capture Northern Migration
Scientists using time lapse photography have documented the migration of caribou and ptarmigan in northern Alaska. The project employed automated cameras to capture thousands of images of spring in the northern foothills of the Brooks Range.
University Of Alaska Fairbanks Ken Tape and fellow ecologist David Gustine with the U.S. Geological Survey set up cameras at sites along a 65 mile stretch off the Dalton Highway in the spring of 2012. Tape says the digital cameras were programmed to snap shots of the sprawling landscape every 15 minutes over about a month beginning in late April.
“It’s pretty fascinating,” Tape said. “What I’ve effectively got to do is watch spring happen in the Arctic from 14 different places sitting behind my computer.”
Tape spent hundreds of hours pouring over 40 thousand images of the view shed, and whatever passed through it.
“I wasn’t really sure that it was gonna work, it was kind of a pilot project, and when I got the data back and I first downloaded a couple cameras I realized that it was a bit of a gold mine,” he said.
Tape describes a landscape changing with the weather, wind bending bushes and drifting snow, but there’s also occasional more lively punctuation, like a curious wolf peering into the lens, or a hungry bear taking center stage.
“[The bear] attacked a caribou outside of the frame; drug the caribou into the frame; and sat there and ate it,” he said. “So things like that you just wouldn’t necessarily, I wasn’t expecting to see.”
What Tape was anticipating is also there.
“Over 5,000 ptarmigan and over 6,000 caribou,” he said.
Scientists typically used GPS collars and aerial surveys to track migration, but cameras offer a less invasive alternative. Tape also points to telling context provided by the photos, images that illustrate not only the volume and location of caribou and ptarmigan, but the surrounding environment.
“The study offers an opportunity to document environmental condition along alongside that migratory pulse,” Tape said.
If conducted over multiple years, Tape believes the time lapse photography technique could help sort out whether and if so, how environmental factors affect Arctic wildlife behaviors like migration, big questions as climate change alters their northern home.