In a twist to the predator-prey debate of the West, where hunters accuse wolves of eating too many elk and Pacific Coast states bemoan federally protected sea lions eating endangered salmon, a fresh menace has emerged: the American white pelican, which anglers say gobbles hatchery-raised rainbow trout and dwindling native Yellowstone cutthroat.
State wildlife managers are reviewing a plan that could include destroying some pelican eggs on islands commandeered by the giant birds to deal with the problem. But to do that, they'd first need approval from the federal U.S. Fish and Wildlife Service, which protects the pelican under the Migratory Bird Treaty Act of 1918.
Whether it's wolves versus elk, sea lions on salmon or pelicans against trout, wildlife managers are increasingly being challenged to weigh competing interests in a landscape where the West's natural balance has been altered by humans. Just as the mighty Columbia River's dams make spawning salmon easy pickings for sea lions, eastern Idaho's reservoirs created predator-free islands for pelicans to multiply.
"They're just like a gang of horse thieves," said retired eastern Idaho rancher Don Allen, who launches his 15 1/2-foot fishing boat from Henry, where a shuttered 100-year-old store is the sole reminder of the area's once-famous cattle roundups. "They get a group of them together, circle an area, then go to work."
Anglers have taken matters into their own hands, illegally releasing pigs or even badgers on the islands to eat the eggs, state officials say.
Wildlife advocates, meanwhile, are concerned sportsmen may have the upper hand in this species-on-species drama because proceeds from fishing license sales help cover state Department of Fish and Game operations. They say federally protected pelicans play an important role in keeping non-game carp and Utah chubs in check.
"I hate to see pelicans treated like vermin," said Chuck Trost, a retired Idaho State University biology professor in Pocatello and president of the local Audubon Society chapter. "Yes, you may be able to save some trout. But there are subtle things that can go on that I'm not sure that fishermen think about."
Bird experts say pelicans likely arrived in Idaho before European settlers, though the creation of vast reservoirs in the early 1900s produced ideal island habitat for the ground-nesting birds. Idaho now has two colonies on islands behind the Snake River's Minidoka Dam near Rupert and in the Blackfoot Reservoir just west of the Idaho-Wyoming border.
In 2003, state biologists counted 1,450 nests between the two colonies, or about 2,900 adult birds.
In 2007, the number of nests had risen to 3,665, or more than 7,200 birds. This year, that's dropped to 2,730 nests, or 5,400 pelicans. The decline is likely due to predation from night herons or ravens, said Colleen Moulton, a Department of Fish and Game non-game species biologist.
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