LOS ANGELES — California is home to some of the most-sweeping legislative and grass-roots efforts to reduce the use of rat poisons deemed unacceptably toxic to wildlife, including a state ban on the retail sale of certain pesticides and far-reaching efforts by nonprofits to encourage home owners to install barn owl nesting boxes to naturally reduce rodent populations.
California’s moves reflect a national shift away from rodenticides that revved up in 2005, when the Environmental Protection Agency was ordered by a federal judge to determine possibilities for reducing poisonings of children and wildlife. By 2008 the agency had developed a risk mitigation decision, which pinpointed 10 chemicals found in a certain type of rodenticide, called second-generation anticoagulants, as most harmful to wildlife and children.
Stella McMillan, the U.S. Department of Fish and Wildlife’s senior environmental scientist in charge of pesticide wildlife investigations for the state of California, told NBC in March that about 70 to 80 percent of animals in the wild are affected by second-generation rodenticides. She said that poisonings have been documented in at least 25 species in California, including northern spotted owls, mountain lions, hawks, minks, coyotes and endangered San Joaquin kit foxes.
An estimated 10,000 children are accidentally poisoned by rodenticides every year, often mistaking the peanut-buttery taste of the colorful pellets for candy.
Second-generation anticoagulants were introduced in the 1980s when rats began developing resistance to first-generation anticoagulants, which have a similar effect but a shorter half-life and are less toxic than their successors. Rodenticides often don’t kill immediately, affecting an animal’s tissues while it remains alive for up to three weeks.
During that time, poisoned rodents can be hunted by wildlife — including birds of prey, bobcats, coyotes and mountain lions, all of which have been found poisoned by first- and second-generation anticoagulant rodenticides in California. Poisoned wildlife suffer from weakened immune systems, which can leave them with painful illnesses like mange, or from disorientation, which increases their risk of being hit by cars.
“Rat poison doesn’t just kill rats, especially the stuff you might be putting out in today’s world,” said Dr. Travis Longcore, an associate professor of spatial sciences at the University of Southern California and the science director of the Urban Wildlands Group, a Los Angeles–based nonprofit. “You do kill rats, but you'll also kill other wildlife, like birds, coyotes and bobcats. We know this because we as scientists have looked at the blood of bobcats and coyotes and mountain lions and documented that there are rodenticides in their blood that affect their immune system.”
As a State Assembly bill banning rodenticide use in state parks made its way to Gov. Jerry Brown’s desk last year, nonprofit groups in Northern and Southern California rallied citizens to set up barn owl nesting boxes in lieu of using rat poisons, in the hope that natural predators would provide rodent control. These state- and citizen-level efforts were bolstered when over 20 municipalities throughout the state — including San Francisco, Berkeley, Marin, Malibu and Calabasas — agreed to restrict the local sale and use of rodenticides.
At the federal level, in February 2013 the EPA filed a notice of intent to cancel 12 products made by popular rodenticide brand D-Con’s manufacturer, Reckitt Benckiser, because they did not meet the standards set in the 2008 risk mitigation decision. According to a special section of D-Con’s frequently asked questions page dedicated to EPA inquiries, the company said that it “challenged attempts to cancel second-generation anticoagulant rodenticide products because of concerns about consumers using alternate products that contain a neurotoxin which, unlike D-Con products, have no known antidote in the case of accidental exposure.”
“Although companies are switching to bromethalin, a rodenticide for which there is no known antidote, there are effective ways to treat bromethalin exposure if it does happen, and we believe exposure is very unlikely when the bait is in a tamper-resistant bait station,” the EPA said.
By May 2014, Reckitt Benckiser and the EPA reached an agreement: D-Con would stop producing the 12 products cited by the EPA — eight of which contain second-generation anticoagulants — and the EPA sanctioned several new D-Con products that contain a new active ingredient that is still responsive to a vitamin K antidote.
“Reckitt’s other products contain either bromethalin or diphacinone. Bromethalin, diphacinone and the other first-generation anticoagulants are less toxic and less persistent and thus less likely to result in death to wildlife that consume poisoned rodents,” the EPA said.
D-Con was mandated to stop selling the banned products to retailers by the end of this March, to begin phase-out of by June and stop producing them by the end of December. California started moving away from rodenticide use months before the agreement was reached.
In February 2014, California State Assembly member Richard Bloom, whose District 50 includes the sprawling Santa Monica Mountains Recreation Area, authored and introduced AB 2657, a sweeping restriction on the use of second-generation anticoagulants in any “environmentally sensitive areas,” focusing on state and national parks. He previously introduced legislation to help protect the state’s bobcat population, which was dropping considerably in areas like Joshua Tree National Park in southeastern California because of human influence, including the presence of rodenticides.
Last March, the California Department of Pesticide Regulation banned the direct-to-consumer sale of rodenticides containing second-generation anticoagulants. However, the ban does not apply to licensed professional pest control companies. The statewide sales restriction went into effect on July 1.
In April, as Bloom’s bill made its way through committees and was narrowed in scope to cover exclusively state park land and exempt certain agricultural companies from the ban, the California Coastal Commission banned the use of rodenticides in the Santa Monica Mountains Recreation Area. That month, Southern California’s attention was dramatically drawn to rodenticides when P-22, a locally famous urban mountain lion that resides under the Hollywood sign in Griffith Park, was found to be poisoned.
P-22 was showcased by National Geographic in December 2013, when a local photographer’s shots of the healthy young puma hunting in the Hollywood Hills were published. His golden coat was shiny and full, his face alert and focused as his muscular body stalked deer. Then in late March 2014, a stationary camera in the park caught the image of the mountain lion — looking disoriented and weak, his skin and fur ravaged by mange, eyes dilated and ears drooping. Park rangers were able to track his radio collar and administer a life-saving dose of vitamin K, but tests revealed two different doses of first generation anticoagulant rodenticide in his blood.
His ravaged health drew increased attention to the cause of banning rat poisons from Los Angeles nature areas. Citizens for Los Angeles Wildlife, or CLAW, a community wildlife nonprofit spawned from efforts to protect Laurel Canyon’s wildlife corridor, increased pressure on the Los Angeles Department of Recreation and Parks to ban the use of rodenticides from over 400 nature areas in the county. Petitions circulated with photos of P-22’s face, encouraging Angelenos to support Bloom’s state park rodenticide ban.
“While second-generation has a longer half-life, it was first-generation that was found in P-22 and is used in squirrel bait. There needs to be more education,” said CLAW co-chairwoman Alison Simard, who hopes future bans will include more types of rodenticides. “We’re saying poison is poison is poison. If your exterminator says that their poison isn’t toxic, tell them to lick it.”
By fall 2014, large steps were made: At the state level, AB 2657 was signed into law in September. At the municipal level, the Department of Recreation and Parks banned the use of second-generation rodenticides in LA nature areas. And at the citizen level, CLAW introduced an effort in September inspired by Northern California’s Hungry Owl Project that encourages homeowners to install barn owl nesting boxes on their property and talk to their neighbors about agreeing as a community to avoid rat poisons and let the owls hunt instead.
“California is frequently a trend-setter state, certainly on environmental issues,” Bloom said. “I think Californians increasingly understand the nature of the ecosystem and are sensitive to the need that we not do things that have a dramatic impact on what is a very complex ecology. There’s a whole list of reasons why it’s important to maintain these very beautiful and important animals.”