Photo Credit: Jim Wilson, The New York Times/Redux
There are almost 30,000 double-crested cormorants that nest on East Sand Island, at the mouth of the Columbia River in Oregon, says an article, by Isabelle Groc, in National Geographic. These cormorants are eating too much salmon and steelhead trout, says the United States government; as a result, the American government is considering killing 16,000 of these birds as a measure to control their population. This raises the question on whether it is ethical and right to kill one species to save another.
That's too many cormorants, says the U.S. government. Starting next spring, it proposes to shoot more than half of the iridescent black birds, on the grounds that they're eating too many fish.This might be one of those cases where the American government is forced, by law, to act unreasonably— protecting an endangered species by killing one not currently endangered. This seems like a bad idea, and the rest of the article raises important questions on why it is important for humans and wildlife to share land and resources, including food. It would seems that human reason can find other less harmful solutions. Killing the birds is a simple and cheap solution to one problem, but it might not be the best answer. And I am persuaded that it is a short-sighted solution that will lead to more problems in a few years, or decades.
The cormorants eat mostly anchovies—but they also dispatch as many as 20 million salmon and steelhead trout smolts every year. The nesting season of double-crested cormorants on East Sand happens to overlap with the migration of the juvenile fish down the Columbia to the Pacific.
"They're eating over 6 percent of all the wild steelhead that are passing through the lower Columbia River," says Ritchie Graves, a fisheries biologist with the National Oceanic and Atmospheric Administration. They also consume more than 2 percent of the yearling chinook salmon.
Besides being commercially valuable, both fish are on the Endangered Species List, and that's what's forcing the U.S. Army Corps of Engineers to act. The corps owns and manages East Sand Island; indeed, it created the bird colony when it expanded the island with dredging spoils back in the 1980s.
Last summer the corps announced a proposal to kill 16,000 double-crested cormorants on the island over a period of four years. It also proposes to remove enough sand to inundate the nesting area of the cormorants, so that birds that leave won't come back. The goal is to reduce the double-crested cormorant population on East Sand Island to about 5,600 breeding pairs.
The move is part of a growing trend toward what wildlife managers sometimes call "lethal control"—killing one species of animal to protect another.
Lethal control of natural predators "is slowly becoming a dominant conservation strategy," says Michael Nelson, a professor of environmental ethics and philosophy at Oregon State University, in Corvallis. "We are embracing this as the first line of defense."
As the strategy is playing out at local levels, it is drawing opponents. That includes Piggott, who is dismayed by the corps' plan to shoot cormorants.
"We have built a level of trust between the researchers and the birds that nest around the blinds," she says. "It makes me sad and angry that we are breaking this relationship and using the blinds against the birds. They have no idea what's coming."
You can read the rest of the article at [NatGeo].