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WILDLIFE CONSERVATION

Saving Loons from Lead Poisoning

A 12-year Tufts study revealing New England loons are dying from lead poisoning has triggered a third state, Massachusetts, to ban lead fishing sinkers from freshwater fishing areas. On June 21, Massachusetts wildlife officials held a public hearing on proposed regulations to ban lead fishing sinkers and jigs on both the Wachusett and Quabbin Reservoirs.

If regulations are approved, as expected, Massachusetts will join New Hampshire and Maine in the growing number of states choosing to regulate lead fishing gear in different ways. New Hampshire enacted legislation banning lead sinkers on all state water areas in January, and Maine has similar legislation taking effect in 2002.

Four other states, including Vermont, New York, Minnesota and Wisconsin, are discussing similar action or have begun educational campaigns.

"With three New England states on board, we're looking to move this initiative to the federal level and expand this kind of protection nationwide," said Dr. Mark Pokras, head of Tufts' Wildlife Clinic at the School of Veterinary Medicine. "With this kind of leadership, we will save the lives of not only hundreds of loons, but many other species of wild birds that fish on freshwater lakes."

Overseas, both Great Britain and Denmark have likewise banned lead fishing gear and Canada has banned lead gear in its state parks. Since 1989, Pokras and fellow Tufts wildlife biologists have conducted animal autopsies on nearly 500 dead loons. They have found that more than half of the adult loons from the region's freshwater lakes and ponds are dying of lead poisoning from lead sinkers.

Loons most likely swallow them when they ingest pebbles to aid in digestion. In the loon's acidic gizzard, the lead breaks down quickly, is absorbed into the blood, and can cause death within two weeks. A single dose of 0.3 grams of lead has proven fatal to loons. Lead sinkers and jigs generally weigh between 0.5 and 15 grams.

Wildlife biologists are crediting Tufts research for propelling the lead safety campaigns. The Tufts School of Veterinary Medicine's Wildlife Clinic is the federally designated center for emergency care and rehabilitation of endangered species in the Northeast.

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