Thought we’d completely dealt with the threat of poisonous lead in our hunting ammunition? Think again

THE SHOTSHELL SITUATION

Lead is a toxic natural element that’s long been known to cause serious health problems in humans, particularly developmental delays in children. It can be found in everything from batteries to water pipes to household dust, and prolonged contact can even be fatal. Wildlife are also not immune. Within both the hunting and scientific communities, the poisoning of birds as a result of ingesting lead pellets has been recognized for more than a century.

As recently as the 1980s, according to the Canadian Wildlife Service, it was estimated up to six million of the approximately 50 to 60 million ducks migrating from Canada every fall had ingested at least one spent lead shotgun pellet. An estimated 200,000 to 360,000 of those birds died, while several million suffered sub-lethal lead poisoning. South of the border, meanwhile, the U.S. Fish and Wildlife Service estimated that two to three per cent of the continental waterfowl population—more than one million ducks and geese—died annually of lead poisoning from ingesting spent shot.

In response, the U.S. and Canadian governments banned the use of lead shot for waterfowl hunting in the 1990s. The hunting community wasn’t happy with the legislation, in part because the replacement steel ammunition of the day performed poorly compared with lead. Over time, however, the ammunition industry invested in research and technology, making significant improvements. As a result, today’s waterfowlers have numerous non-toxic options, many of which outperform lead.

While it was controversial at the time, the banning of lead shot for waterfowling appears to have worked

While it was controversial at the time, the banning of lead shot for waterfowling appears to have worked—a study of black ducks in the eastern U.S., for example, revealed the percentage of ducks with toxic blood levels declined from 19 per cent in 1978 to just one per cent in 2017. At the same time, however, hunters are still permitted to use lead shot for upland game birds.

Although we seldom associate the harmful effects of spent lead shot with upland birds, research in New Brunswick, South Dakota, Utah and elsewhere has shown that some woodcock, pheasant and quail populations have elevated lead concentrations consistent with consuming lead pellets. In one study, scientists fed three groups of bobwhite quail with one, five and 10 pellets, respectively; the groups that were fed five or 10 pellets exhibited health declines within seven to 14 days. And a 2015 study in South Dakota showed that wild pheasants living in areas with artificially high hunting intensity—near release sites, for example—faced an elevated risk of lead exposure and poisoning.

Here in Canada, the way upland birds occupy their habitat, and the density of hunters, suggests most birds are unlikely to encounter spent lead shot, but the risk can’t be completely ignored. Far more worrisome is the potential harm to wildlife from lead-core rifle ammunition.