Biologists Planning Long Look at Pelicans
BISMARCK, N.D. (AP) — Federal biologists trying to solve the mystery of why 28,000 pelicans left Chase Lake National Wildlife Refuge last year have bought electronic tracking devices for the birds.
But for the plan to work, the pelicans will have to return to the refuge near Medina.
Wildlife officials are confident they will come back – and earlier than normal.
“We’re predicting they’ll start coming back next week,” said Ken Torkelson, a spokesman for the U.S. Fish and Wildlife Service in Bismarck. “Their normal return date is anywhere from April 10 to 15.”
The birds are currently at their winter grounds in Florida, Louisiana, and Mississippi, Torkelson said. Chase Lake was still frozen on Thursday, he said.
The big birds returned last April to nest, as they have for at least a century. But they took off in late May and early June, abandoning their chicks and eggs. The 4,385-acre Chase Lake refuge had been the site of the largest nesting colony of white pelicans in North America.
Biologists checked air, water and soil quality at the site. They also have checked for diseases, food supply, predators and other possible factors to solve the mystery of why the pelicans abandoned their young.
Biologists are still baffled. “We may never know,” Torkelson said.
He said electronic tracking equipment will be harnessed to 10 pelicans at Chase Lake. Long-range video surveillance cameras and extra crews also will monitor the pelicans this year.
Torkelson said each tracking device costs about $4,000. The device will give a pelican’s location, altitude, speed and heading.
“We’re hoping to learn how much time they spend at the colony and where they go when they leave the colony,” Torkelson said. “We’re also hoping to learn more about their foraging sites.”
A fence will be installed around one nesting colony to keep out predators.
Backpack-like tracking devices also will be attached to five pelicans at Medicine Lake National Wildlife Refuge in northeast Montana, between the Missouri River and the Canadian border. Additional monitoring of pelicans also is planned at Waubay National Wildlife Refuge in northeast South Dakota.
Only the North Dakota refuge had a premature exodus of pelicans last year, Torkelson said.
Pelican nesting grounds will be off-limits to the public this year at Chase Lake, he said. Wildlife officials also have installed signs around the refuge, telling people to stay away.
Visitors still will be able to see pelicans feeding at prairie potholes in the Chase Lake area, Torkelson said.