Lethal Means Explored to Fend Off Birds’ Predators

Federal wildlife experts say the snowy plover is endangered because their eggs are being eaten by birds, skunks, feral cats, raccoons and red foxes. This month they will start allowing the killing of plover predators.

Larry Mangan, a senior wildlife biologist with the U.S. Bureau of Land Management, which oversees much of Oregon’s plover habitat, acknowledged the plan is controversial with biologists and among land managers.

“But we’ve tried as much as we can with nonlethal means in the past,” he said. “And we’ve come to the conclusion that we really can’t recover the species in Oregon without more predator management.”

The decision authorizes methods such as shooting, poisoning, euthanizing trapped animals and destroying nests and eggs of airborne predators. The plan urges that nonlethal alternatives be fully explored before killing begins, however.

Biologists and others have struggled to protect the nests, finding as many as possible and surrounding them with large wire exclosures to keep out airborne predators.

But the predators often find their way in, or kill the fledgling plovers when they make their way out.

The main culprits are crows, said Mark Stern of the Nature Conservancy’s Oregon Natural Heritage Program. He said crows and ravens sit on the edge of the exclosures, then drop between the wires, which are about 4 inches apart.

According to the environmental assessment, crows and ravens accounted for more than 40% of the predator-caused nest failures along the Oregon Coast over a 10-year period.

Carl Frounfelker, a Siuslaw National Forest wildlife biologist, says he would like to try nonlethal means, such as electrifying the wires on the top of the exclosures.

Mangan said the last resort would be poison.

Foxes and other four-legged predators would be caught in “soft” leg-hold traps, Mangan said. Except for feral cats, trapped animals would most likely be euthanized rather than relocated, he said.

The cats would probably be taken to nearby humane societies. None of the lethal measures would be used in areas where humans or pets might be endangered, he said.

There have been some public objections to the plan, including arguments that predators are being made a scapegoat for plover losses that could be better addressed through habitat improvements.

Mangan and Stern agreed that measures such as improving habitat and reducing conflicts with human activity are important, but they also see better predator control as an important part of the effort.

Dave Williams is director of the Portland wildlife services office of the Agriculture Department’s Animal and Plant Health Inspection Service, which will contract for the control work.

He said he expects more protests after predator killing begins, noting that some people object to killing any wildlife.

How much the new predator-control program will help the plover recovery remains to be seen.

Mangan hopes it will lead to more nests that produce fledglings, and more fledglings that survive the month between hatching and the time they’re able to fly.

“We wouldn’t do this if we didn’t think there was good chance for success,” he said.