Wildlife Poisonings
Poison manufacturers and consumers are killing California's wildlife and polluting the commons
OPEN LETTER TO THE CALIFORNIA SENATE APPROPRIATIONS COMMITTEE
August 30, 2023
Senate Appropriations Committee
State Capitol, Room 412
Sacramento, CA 95814
(916) 651-4101
Senator Anthony J. Portantino, committee chair
Senator Angelique V. Ashby
Senator Steven Bradford
Senator Aisha Wahab
Senator Scott D. Wiener
Dear Chair Portantino and Committee Members,
I strongly support the California Ecosystems Protection Act of 2023 (AB 1322), which would protect California wildlife and communities against harmful rodenticides. I urge you to advance the bill past Senate Appropriations and extend the moratorium on diphacinone and other anticoagulant rat poisons throughout the state.
As a volunteer with a wildlife rescue and rehabilitation organization, I have seen firsthand how destructive these poisons are to California's native wildlife. In my own semi-rural neighborhood in North San Diego County, I have seen and documented wild bobcats suffering and dying from diphacinone poisoning, and constant, recurring cases of indigenous coyotes being poisoned and disfigured.
As you know, mountain lions, coyotes, bobcats, and birds of prey, all suffer and die from having eaten rats poisoned with diphacinone and other anticoagulant poisons.
Wild coyotes that ingest anticoagulant-poisons like diphacinone suffer from horrible symptoms and exposure for up to two years before dying—but not before losing their ability to hunt for themselves and resorting to scavenging closer and closer to people’s homes and businesses, where they encounter people and more rat poison. Hawks, owls, and condors are very susceptible to diphacinone poisoning too, as you know, but the toll on them is likely vastly undercounted, as they typically don’t live long enough after being poisoned for anyone to intervene.
These "secondary poisonings" are not only tragic in humanitarian terms, but as a matter of simple resource management they are also wasteful and counterproductive, since these same native predators are essential to keeping the rodent population under control. Even casual hunters understand and embrace the important role apex predators play in their native environments, and your committee will not find a single pest control or poison industry representative who would deny the undesirability of indiscriminately poisoning California's native wildlife. Everyone with any interest or stake in California’s wildlife, natural resources, and beauty should object to the use of diphacinone and anticoagulant poisons like it.
Despite our best efforts, though, the public is simply not aware of the harm poisons like diphacinone cause. The poison manufacturers and pest control companies offer the public a simple solution—with ongoing service contracts and billing, of course—but don't bother informing their own customers of the downsides; the real, significant costs and harm they are blithely shifting onto wildlife by distributing poison in their customers' neighborhoods.
I have personally spoken with homeowners and commercial property owners in urban, rural, and semi-rural communities who ask how they can help the sick and maimed coyotes and bobcats they see in their neighborhoods. They are distressed to learn that their own diphacinone anticoagulant rat poison bait stations are killing their local wildlife.
At the same time, I have spoken with and documented commercial property managers who pay monthly fees to have diphacinone bait stations spread and regularly refilled around their properties, right next to trash cans overflowing with food waste; the pest control companies have no incentive to inform them of even the most basic and low-cost rodent mitigation techniques. At every stage, people shift their costs and poison pollution to someone else, and the ultimate burden falls on wildlife.
But the Committee should be aware more than simple ignorance or carelessness are at work. I've been involved in cases where pest control companies (with prominent brand names you would certainly recognize) not only mislabel the diphacinone they are distributing, but outright lie to their customers about its dangers to pets and wildlife. In two unrelated cases, at my urging, concerned commercial property managers have called their pest control service providers specifically to ask if the sick bobcat and many gravely ill coyotes on their properties might be being harmed by their diphacinone bait stations. Three separate representatives from their pest control service providers flatly lied, saying diphacinone (specifically Bell Labs' diphacinone product, Ditrac) posed no risk at all to wildlife. This despite the poison manufacturer's own clear warnings about the risks of secondary wildlife and pet poisonings and environmental contamination. I’m sure you could observe similar deceptive and dangerous responses by calling your own local pest control service providers.
Ignorance, indifference, and motivated deception explain the countless innocuous looking diphacinone bait stations outside almost every commercial and multi-unit residential property in the state, poisoning our native predators by the tens of thousands and polluting the environment. And it's a special kind of indifference because, of course, those same bait stations feed and attract rats, which reproduce faster than they can possibly be poisoned, and so exacerbate the problem.
To illustrate the gore and suffering caused by secondary diphacinone poisonings, I attach a copy of a field report I compiled over six months of observations of just one neighborhood in Oceanside, North San Diego County, where homeowners, HOAs, and commercial property owners using diphacinone poison bait stations have been unwittingly poisoning the coyotes—and, no doubt, the bobcats, hawks, and owls—that live in a nearby nature reserve.
I have recently written to the Natural Resources and Water Committee to urge its members to support AB1322 to place a moratorium on the use of diphacinone poison throughout California, as well as to the California Department of Pesticide Regulation to urge it to formally reevaluate its use, and now I urge you and your Committee members to advance the bill past Senate Appropriations.
Thank you,
Cosmo Wenman
San Diego, California
cosmo.wenman@gmail.com
310-780-5130
Sick Wildlife in the Fire Mountain Community
Wildlife Care of Southern California (WCSC) is a non-profit organization with city, state, federal, and USDA permits to rehabilitate native wild animals. Since 2017, it has been researching the treatment of mange in bobcats and coyotes in the field and is in the process of monitoring, documenting, and assessing the current condition of multiple individuals in and around the Fire Mountain community, Oceanside, CA. This report was prepared by WCSC volunteer and North County resident Cosmo Wenman. For more information contact him at cosmo.wenman@gmail.com or visit wildlifecareofventura.org.
Several of Fire Mountain’s native coyotes are desperately ill and urgently need aid. You can help the neighborhood’s sick wildlife by immediately pausing the use of rat poison.
Please talk with your neighbors, HOA, and neighboring businesses about removing poison-bait stations and transitioning to poison-free, effective, and ecologically non-hazardous rodent mitigation options.
Fire Mountain’s Sick Wildlife
Of the neighborhood’s 12 or more coyotes, at least six are sick.
At least one puppy is sick. There may be a second and third puppy that are healthy.
The puppies' adult mother is also sick and rapidly deteriorating. If the mother becomes unable to hunt effectively in the coming weeks, her puppies may not survive. The puppies are very small, around only 15 inches tall and around 12 lbs., and they are not yet hunting for themselves.
At least two additional adult coyotes are very ill, one of which is underweight and has multiple bleeding lesions.
Three additional adults have been observed with signs of early stages of illness.
These symptoms and extraordinarily high incidence rate of illness are consistent with poisoning. The direct cause of the coyotes' illness is likely secondary poisonings from rat poison bait stations.
Fire Mountain’s Wildlife and Secondary Poisonings
When an animal ingests poison by eating poisoned prey, it is referred to as a "secondary poisoning." The US National Parks Service and the California Department of Fish and Wildlife have determined secondary poisonings from rodent poison cause death and debilitating mange in several species of California wildlife.
A healthy immune system usually keeps the microscopic mites that live on all mammals in check, but when bobcats, mountain lions, and coyotes eat rodents poisoned with anticoagulants, their immune systems become compromised; their mite populations explode, resulting in mange. Animals sick with mange lose their fur and develop painful skin lesions over their entire bodies. Bobcats with mange die within months. Coyotes with mange can suffer for as long as one to two years before they die of dehydration, starvation, exposure, and secondary infections.
The effects of secondary poisonings can been seen in the disconcerting and sad appearance of several of the neighborhood’s gravely ill coyotes. Coyotes suffering from mange lose the ability to hunt for themselves, leave their packs, and scavenge closer and closer to homes during the daytime. For this reason, poisoned, sick coyotes are far more visible to the public.
Secondary poisonings to neighborhood coyotes, hawks, and owls are happening on a regular basis.
Neighborhood Poison Stations and Pest Control Services
It is not uncommon for pest control service providers to misinform homeowners and businesses about the hazards their poisons pose to wildlife. They know that many of their clients would be upset to learn that their own poisoned bait stations may be killing and causing suffering in native wildlife.
Black, shoebox-sized poisoned bait stations are a common sight outside commercial properties and many commercially managed residential buildings. These boxes are not rat traps. Their intended function is to attract rodents and distribute poison. Rodents enter the stations, eat the poison, then leave to die outside where they are consumed by wildlife. Pest control service providers typically refill these dispensers with poison on a monthly basis and charge their clients for regularly scheduled refills, with little concern for harm to wildlife.
Ask your pest control service provider which poison they are distributing on your property, common HOA areas, and in your neighborhood. Ask them about secondary poisonings and the risks to owls, hawks, bobcats, coyotes, and pets. Compare their response to the poison manufacturer’s own warning labels and official statements, and advisories from the EPA and the US National Parks Service.
Poison bait boxes typically use anticoagulant poisons such as Bromadiolone, Brodifacoum, Cholecalciferol, Diphacinone, and Difethialone, which cause death by internal bleeding. Bell Labs’ own product labels for its Diphacinone products (Ditrac) include this very clear, serious warning about harm to wildlife:
The US Environmental Protection Agency's National Pesticide Information Center describes Diphacinone, used in Ditrac, as "high risk" for secondary poisonings in mammals: NPIC.orst.edu/factsheets/rodenticides.html
Bell Labs declares to the US Environmental Protection Agency that Ditrac is "extremely toxic to mammals, birds and other wildlife" and specifically notes the risk of secondary poisoning: EPA.gov/pesticides/chem_search/ppls/012455-00080-20200729.pdf
The US National Park Service warns about wildlife secondary poisonings from Diphacinone in Southern California: PROJECTCOYOTE.org/wp-content/uploads/2017/02/rodent-infographic041714.pdf
BASF’s declares to EPA that its Cholecalciferol product (Selontra) is toxic to wildlife via secondary poisoning
Anticoagulant poisons that are chemically similar to Ditrac's Diphacinone have recently been banned outright throughout California, specifically because of secondary poisonings in wildlife.
The Neighborhood’s Rodent Control Strategy
Fire Mountain’s indigenous owls, hawks, falcons, bobcats, and coyotes catch many thousands of rodents every year—many times more than poison bait boxes or any pest control company could ever eliminate. A single coyote will eat up to 1,800 rodents per year. A single hawk can eat up to 2,900 mice per year. A family of owls will eat up to 3,000 gophers per year. These native predators are essential to keeping the neighborhood's rodent population under control and are the most effective pest control service its homeowners could hope to have working for them.
Despite this, several homeowners, HOAs, and businesses in the neighborhood use poison bait stations. It is important to realize these stations are not traps. Their intended function is to attract rodents and distribute poison.
Rodents enter the stations, eat the poison, then eventually die nearby. Poisoned rodents become sick and lethargic and make for easy targets for the neighborhood's wildlife. Rats and mice that eat the poison are consumed by natural predators or scavengers.
The neighborhood’s wildlife is extremely vulnerable to consuming dead or dying rodents that have been poisoned by these stations. It is possible the neighborhood’s coyotes, in particular, are habituated to seeking dead or lethargic poisoned rodents near homes and businesses with poison bait stations.
The homeowners’ and businesses’ own poison bait stations not only attracts rats, but actively undermine their most effective pest control; every coyote, hawk, and owl incapacitated or killed by poison would eat many hundreds to thousands of rodents each year.
Helping the Neighborhood’s Sick Wildlife
Wildlife Care of Southern California is currently monitoring, documenting, and assessing the condition and treatment of multiple sick coyotes in and around the Fire Mountain community, Oceanside, CA.
The most effective action the neighborhood can take to help its sick and injured wildlife right away is to:
Please consider immediately pausing the use of poisons.
A pause will help the remaining healthy coyotes avoid getting sick while the sick individuals are tracked and monitored through recovery. If poison is not removed, coyotes that have already been treated will become sick again. Even a temporary pause of a few months would be a big help in saving the sick adults and puppies before it is too late. Please consider at least temporarily pausing the use of poisons right away while we all try to help the coyotes that are already sick. If you have hired a pest control company, please direct it to immediately collect all poison from all its poison stations and to stop refilling them until further notice. Direct them to give you (or your HOA or commercial property management) a list of the locations of all poison stations throughout the property so they can be verified to be empty.Evaluate and monitor "exclusion" measures to prevent rodents from being attracted to your property and entering buildings. Pest control service providers offer exclusion consultations and services, which can be quite effective. You can use their exclusion services while directing them to not use poisons on your property, to remove their poison bait stations, and stop charging you for poison refills. Keep dumpsters closed and the areas around them clean and free of loose food waste. Keep common areas clean and trash free. Trim back brush in yards and common areas where rats may nest.
Switch to ecologically safe, effective, poison-free traps and other rodent mitigation options, including those that may not require any expensive service contracts. Evaluate poison-free traps such as those offered by goodnature.co, for example, which are endorsed by the American Bird Conservancy, the American Eagle Foundation, The International Owl Center, The Raptor Institute, and others. Periodically re-evaluate and monitor rodent exclusion and mitigation requirements.
Permanently remove unused poison bait stations from your property. Removing unused bait stations will help us identify the specific sources of any future wildlife poisonings in the area.
POISON-FREE Rat & Mouse Traps
Goodnature Traps, available at Goodnature.co and Amazon.com
Cosmo Wenman is CEO of Concept Realizations. He can be contacted at twitter.com/CosmoWenman and cosmo.wenman@gmail.com
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DOCUMENTS
My letter and field report:
Information about AB 1322: