From Montreal, at a meeting of the Society of Environmental Toxicology and Chemistry
Since 1999, more than 2,100 trumpeter swans in northwest Washington and southwest British Columbia have died—about 15 percent of the birds that winter in this region. Nearly 80 percent of the deaths occurred because the birds ate lead shotgun pellets, reports a U.S.–Canadian team of researchers.
Some 25,000 trumpeter swans breed in this region and other North American areas along the Pacific, notes team member Laurie Wilson, a wildlife biologist with Environment Canada in Delta, British Columbia. Over the past several decades, these swans have been climbing back from the brink of extinction, so the high death rate from lead poisoning is especially troubling.
To date, the team has autopsied more than 1,700 carcasses. "We're recovering, on average, 22 lead pellets" per bird, says Wilson. However, she adds, more than 4 percent of the birds had gizzards containin