Gallery: U.S. Geological Survey collect data for bobcats population
Scientific research connecting dead wildlife to household and industrial use of rat poison has led to a movement among cities, the National Park Service and even the U.S. Environmental Protection Agency to limit the sale, purchase and outdoor use of certain rodenticides.
Last week, the city of Malibu passed a resolution opposing the use of rodenticides, which not only kill rats but is leading to the deaths of wild birds and small mammals as the poison works its way up the food chain in hillside and mountainous habitats.
Malibu's resolution, which has already led to removal of rat poison from the shelves of hardware stores and supermarkets in the coastal city, could become a model for other cities throughout Los Angeles County.
Lengthy studies done by the NPS and UCLA found that carnivores prowling the untouched Santa Monica Mountains were dying after eating mice, gophers, squirrels and rats that had ingested rodenticides. The secondary exposure either killed the wildlife directly, or compromised their immune systems and left them vulnerable to common diseases such as mange, which often became deadly.
NPS research ecologists said 92 percent of bobcats studied after death had traces of anti-coagulant rodenticides in their bodies, as well as seven of eight mountain lions and 83 percent of coyotes. Exposures included multiple kinds of rat poisons, sometimes in large amounts, according to a July 8 letter from the U.S. Department of the Interior/NPS to the Malibu City Council in favor of Malibu's resolution.
Recently, this newspaper reported on a new U.S. Geological Survey study of bobcats in the Whittier-Puente Hills that shows similar exposures of rat poison in bobcats who contracted mange. So far, one bobcat has died and the other, a male code-named ZEK, remains in a veterinarian's care, according to USGS researchers and the Puente Hills Habitat Preservation Authority, the group that manages the hillside preserve stretching from Whittier to Rowland Heights.
PHHPA President and Whittier City Councilman Bob Henderson said he will bring up the idea of passing a resolution with the Authority board. He also wants L.A. County cities that share borders with wild lands to urge bans.
"I will introduce an item of discussion at the Whittier City Council to see if we can get some momentum going to try to get protection around the hills," he said Monday. "It would be nice if we could get that adopted throughout Southern California."
The California Department of Fish and Wildlife is working with the state Department of Pesticide Regulation to restrict the use of certain rodenticides to only certified users, according to the CDFW's blog.
The CDFW suggests homeowners use traps instead of poison to catch and kill rodents. They urge homeowners living near open space to avoid any products with the active ingredients brodifacoum, bromadiolone, difethialone and difenacoum.
The CDFW has tested "hundreds of carcasses of wildlife" that have died as a result of exposure to rodenticides, including: mountain lions, bobcats, golden eagles, great horned owls, barn owls, Cooper's hawks, red-shouldered hawks, red-tailed hawks, American kestrels, Canada geese, red foxes, gray foxes, San Joaquin kit foxes and even black bears, according to a blog by CDFW researcher Stella McMillin.
The U.S. EPA received some push-back last March when it tried to cancel 12 of the company Reckitt Benckiser Inc.'s products containing rodenticides. These 12 products marketed under the name D-Con did not comply with EPA safety standards and posed "unreasonable risks to children, pets and wildlife," according to a written statement by the EPA.
The company declined to voluntarily implement the measure, according to the EPA.
The list of products the EPA proposes to ban included: D-Con Bait Pellets, D-Con Bait Packs, D-Con Mouse Prufe Kills Mice and others with similar names. (See http://epa.gov/pesticides/mice-and-rats/cancellation-process.html#cancellation for the full list of products the EPA is proposing to ban).
Sally Barngrove, a resident of Pasadena, spotted two bobcats frolicking in the backyard of her Lower Arroyo home a few months ago. She and others, including conservationist Ann Scheid, are concerned about the bobcat population living on the west side of the Arroyo Seco.
Last year, Barngrove saw two open rat poison containers beneath archery targets in the Lower Arroyo. She and others reported the find and she said it appears whoever put out the poison has stopped the practice.
Kian Schulman, secretary with the Malibu Agricultural Society, said she's pleased with Malibu's response to her group's efforts. She said the Ralph's, CVS and the local hardware store have stopped selling D-Con and other rodenticides.
"It (Malibu's resolution) is a great step for our local bobcats and for other wildlife, which we intend to extend to other cities in the Santa Monica Mountains area," Schulman said.