A recent decision by the Environmental Protection Agency could prove a small but important step in stopping a deadly epidemic in urban areas among owls, hawks and bobcats. On June 10 the EPA banned four of the most potent rat poisons for consumer use. Also called “second generation” rodenticides because they’ve been showing up for years in the livers of the predators that help keep rat populations in check, the toxins stop blood from clotting and cause fatal hemorrhaging in animals that have ingested it. The decision bans products like D-Con, Hot Shot and Generation from being sold in stores.
“I didn’t expect this,” says Maggie Sergio, solutions director for WildCare in San Francisco, which has been pressuring the EPA to take action for months. “And I’m extremely encouraged by it.”
Sergio says producers may put up a fight in court, and the EPA does not know how long it will take to actually clear the products off shelves. And regardless, their toxic effects could linger. Anticoagulant rodenticides can stay in an animal’s system for up to 300 days, Sergio says.
The problem has been widespread. According to the state Department of Fish and Game, 79 percent of endangered San Joaquin kit foxes in the Bakersfield area turned up positive for rodenticide. Near Los Angeles, 90 percent of bobcats sampled had rat poison in their blood. WildCare has partnered with the Pelagic Shark Research Center to see if the strange rash of leopard sharks turning up on the beach with signs of hemorrhaging is linked to rat poison.
Rebecca Dmytryk of WildRescue in Moss Landing routinely finds birds that she suspects have died of rat poison and worries the ban on consumer use won’t address what she calls the real root of the problem: agriculture, where farmers still fight pests with boxes of deadly pellets. “How many barn owls are living in [residential areas]?” says Dmytryk. “There’s more exposure in agriculture and wild lands.”
Thomas Wittman, owner of Gophers Limited, also fears rodenticide use will continue unabated on area farms until people find new ways of controlling rats and mice. “It’s going to be a problem, but there are going to be really sure alternatives,” he says. Wittman, now board president of the Ecological Farming Association, first began experimenting with nontoxic ways to control rats, mice and gophers during time he spent at the UC–Santa Cruz Farm and Garden. He says his was the first pest control business to be certified by the Monterey Bay Area Green Business Program. Wittman’s most popular trick, called the Cinch Sure Catch, looks like an extendable grabber and rests on the gopher hole, where it waits for an unsuspecting victim.
Unfortunately the ban is not complete. The product can still be applied by professionals, and the U.S. Fish & Wildlife Service is discussing a plan to dump more than 1,000 pounds of brodifacoum—one of the substances banned for consumer use—on the Farallon Islands just west of San Francisco to remove nonnative house mice whose disruptive presence threatens the endangered Ashy storm-petrel. The agency has received public comments, including a petition from WildCare with 2,700 signatures, and plans to produce a draft environmental impact statement in the fall, at which point more comments will be taken.
Sergio, meanwhile, says the next target is the professional pest control companies, which have “huge” contracts and can still use the banned subtances. “The first step is getting it banned at a consumer level, and that’s wonderful,” she says. “The next step is getting it out of the market altogether.”
