Bobcats Are the Latest Victims of Rat Poison in California

Poisons meant to kill rodents are indiscriminately killing everything else, including birds and animals that prey on them

The recent deaths of three bobcats in Santa Cruz, CA are yet more tragic evidence of the toll rat poison is taking on our wildlife and how it has infiltrated the environment. One of the bobcats still had a young kitten with her, who ran off when Duane Titus, with Wildlife Emergency Services, approached them. The two other bobcats were hit by cars.

Bobcat in the wildPhoto by Dave HarperA wild bobcat in Contra Costa County. Most animals are not exposed to just one poison but a toxic cocktail of several different types of poison.

We know that when predatory animals — like bobcats, mountain lions, and birds of prey — eat poisoned rodents, they often bleed to death or become very ill. We also know that even if rat poison does not kill an animal directly, it can affect their health pretty seriously. Some of the sub-lethal effects include reduced oxygen supply, weakness, anorexia, depression, excessive thirst, liver damage, and increased bruising. The two bobcats that were hit by cars may have been weakened and slowed down due to the presence of anticoagulant poisons in their systems: Recently, several racehorses who had consumed just trace amounts of rat poison died of internal bleeding after exercise.

What impacts might rat poison have on a raptor — eagle, hawk, or owl — pursuing prey at high speed? A Cooper’s hawk killed in Berkeley a few years ago by a cat that was barely more than a kitten was probably weakened and downed in the first place, making it possible for such a small cat to catch it. That hawk tested positive for several different rat poisons. Most animals are not exposed to just one poison but a toxic cocktail of several different types of poison.

State and federal regulators have imposed new regulations limiting the types of rat poison that can be purchased over the counter. As of July 2014, Californians can no longer purchase “second generation” rat poisons at hardware and other stores; as of April 1, 2015, no one in the United States will be able to buy them over the counter. But two huge problems remain. Pest control companies and agricultural users were exempted and can still use the very worst poisons.

Regulators have stated that pest control companies use poison “more responsibly” than homeowners. While any less poison in the environment is a good step, the regulatory agencies admit that they do not have any real evidence that poison from pest control companies is any less harmful than poison used by homeowners. Poison in a bait box —whether put out by a pest control company or a homeowner — is poison, period. While bait boxes used by pest control companies might be a little safer for some pets and children, they aren’t doing much for wildlife — or even housecats that prey on rodents.

Unlike the old roach “motels,” where a roach could “check in,” but not check back out, rats and mice (who don’t care who puts the bait out or how “responsibly” they do it) enter the bait box, eat the poison, come back out, poisoned, and become toxic, easy prey for a red-tailed hawk, a great horned owl, a bobcat, or a housecat.

A Great Horned Owlin a treePhoto by Pam DimelerrIn a 2012 study, WildCare, a wildlife rehab facility in San Rafael, found that over 75 percent of the animals it tested had some amount of rodenticides in their systems.

Meanwhile, consumers can still purchase a plethora of first generation rat poisons. Although slower acting, those chemicals have been implicated in the deaths of hundreds, if not thousands, of wildlife throughout California: bald eagles, hawks, owls, Canada geese, turkey vultures, bobcats, mountain lions, and many other species.

In Southern California, exposure to first generation anticoagulants has caused both mountain lions and bobcats to suffer severe cases of mange. Last year, one Southern California mountain lion, known as “P-22,” who was famous for appearing in National Geographic magazine, had to be captured and treated for rodenticide exposure. It is not known whether he will fully recover.

In a 2012 study, WildCare, a wildlife rehab facility in San Rafael, found that over 75 percent of the animals it tested had some amount of rodenticides in their systems. It is all too obvious that these poisons —meant to kill rodents but indiscriminately killing everything else, including people’s pet dogs and cats —have infiltrated our environment.

Pest control companies make a lot of money with their “responsible” bait boxes, keeping customers coming back for more all the time. The idea that they are “controlling” rats is somewhat misleading: if you use bait, you’ll be sure to have rats coming back for more too. If we can’t stop using these products — and the government, beholden to the pest control industry, won’t take them off the market — these products need to be renamed for what they really are. “Rat poison” or “rat bait” is really “wildlife poison” and “pet bait.”

Meanwhile, we continue to poison one of the very best solutions to our rodent problem. One red-shouldered hawk can eat as many as 300 rats per year; one barn owl can eat as many as 1,500 mice, rats, voles, and gophers per year. If we humans could do our part by cleaning up birdseed and trash, removing ivy (which rats love to roost in), elevating chicken coops, using non-toxic snap traps, finding out where rats are getting into our homes and blocking their way in — we would be enabling raptors and other wildlife do their job and provide us with free and safe pest control services.

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