Deer, and fawns
Julia J. Di Sieno
Animal Rescue Team, inc.
Young deer are called fawns. Fawns are often found alone, because they do not flee from danger until about 14 days of age, and they do not forage with their mother until they are older. To escape detection a fawn lies motionless in tall grass or other cover. Its spotted coat helps it blend into its surroundings by imitating dappled sun on vegetation. A fawn’s lack of scent also helps to protect it from detection by predators.
The condition of an orphaned fawn will deteriorate quickly if it is not nursing. If you are sure that the fawn is orphaned, or if it is injured, call a wildlife rehabilitator. Fawns require special care. Do not feed the fawn or attempt to care for it yourself. It is illegal to keep a fawn unless you have a permit. Taking a fawn from its natural habitat and teaching it to associate food with humans is doing the fawn a disservice. Once the fawn matures, it will be too large to stay in a house or garage. These deer are often released in a natural area once they are grown, but they are likely to suffer an early death. Human habituated deer may also pose a danger to pets and people, especially during deer mating season.
LIVING WITH LIONS PROJECT
Promoting Non-Lethal Predator Control Alternatives
NATURAL RODENT DETERRENTS
1) Rodents and especially mice are allergic to oil of peppermint and will not frequent a property where they can smell
it. If you place a few drops of oil of peppermint on a piece of cotton and place it anywhere you feel that there is a
mouse problem, you will never see them again. Use only the “real” oil of peppermint, not peppermint extract, for the
best results. You can also plant peppermint in your garden to keep all types of rodents away from the plants. They are
also repelled by camphor and pine tar.
2) There are a few ground covers that rodents do not like to live in or be around. These are adjuga, carpet bugle, cape
weed, chamomile, Indian rock strawberry and creeping speed well.
3) Hire some barn owls to address your rodent problem by installing some nesting boxes. A family of 6 barn owls can
consume as many as 16 or more rats in one night.
4) Rodents will avoid certain plants that give off repulsive scents. These include daffodils, hyancinths and scillia.
5) Gopher purge (uphorbia lathyrus) is a plant that contains pods each containing three seeds. The plant is a natural
repellent to gophers and moles and all other burrowing animals. The roots are so poisonous to them as well as to
humans and it will eliminate the problem.
6) Keep all trash + food tightly contained, woodpiles and debri picked up, drainage pipes clean and fi ll the ends with
chicken wire to prevent rats from entering and setting up house, also remove bird feeders until the problem is under control. Natural Pest Control Internet Sites: Critter-repellent.com
THERE ARE ALTERNATIVES TO POISON
Learn more environmentally-friendly
non toxic gardening practices at:
(click on pests and diseases)
(click on environmentally preferable
purchasing and then on less toxic gardening/IPM)
National Pest Information Center:
Alternatives to Anticoagulant Poisons
For the sake of our native wildlife, please use alternatives to rat poisons. Integrated pest management is an excellent alternative to widespread poison use. Replacing anticoagulants with another poison is not a practice we encourage. The bottom line is that no poisons available on the market in the U.S. have zero risk of unintended consequences for wildlife.
The best pest control is to encourage natural predators. Nesting boxes and perches for owls can be installed around your homes (see HungryOwl for more information).
The next best step to take is to take a preventive mode of action. Rodent proof your homes by sealing up holes. Remove unnecessary vegetation and trash in your yard that could be homes for small mammals. If ground squirrels are a problem, remove food and water sources such as bird feeders and baths!
Finally, once you’ve taken the above steps, try mechanical traps. Wooden snap traps and electric zappers are good for within home use. Just be careful with using snap traps outside. You might catch and injure other wildlife such as raccoons, opossums, coyotes, owls or other birds that will also be attracted to the bait. If you have pets, they too could fall victim to snap traps.
Here’s some suggestions for particular pests:
Rats and Mice
The rats and mice that people target in southern California may be both native and nonnative rats and mice. The most frequent method of rodent control used worldwide are anticoagulant rodentcides. However, we recommend NOT using any poisons at all! Whether you use the poisons inside your home only, or both in and outdoors, you put other wildlife at risk of being poisoned too. Plus, pets and children are not immune to the effects of these poisons either.
Are there safer, effective ways to control rats and mice?
Yes! Visit www.ipm.ucdavis.edu/PDF/QT/qtrats.pdf for details.
- Seal holes inside and outside buildings to prevent entry by rats and mice.
- Keep areas clean and free of crumbs and water. Seal food in rodent-proof containers.
- Use snap-traps instead of baits whenever possible – a lot of them, set at night. Keep the traps indoor where wildlife such as raccoons, coyotes, oppossums, etc. won’t become accidental victims of the snap traps.
- In extreme cases, call a qualified professional. We recommend companies that are certified by EcoWise or GreenShield.
Within the southern California area, a lot of people consider our native pocket gophers a big problem around their gardens and lawns. Pocket gophers are strictly herbivorous, and will often pull plants into the ground by the roots to consume them in the safety of its burrow, where it spends 90% of its life. The burrows of this species may reach lengths of more than 150 meters. The main predators of pocket gophers include badgers, coyotes, long-tailed weasels, bobcats, snakes, skunks, owls, and hawks. Despite their many predators, they are frequent targets of poisoning, particularly with the use of anticoagulant rodenticides.
Prevention and Control
Once you become aware of unwanted gopher activity, it is important to act quickly. Once a tunnel system is in place, other gophers can quickly replace any you may drive away. Various methods can help to repel gophers, but very few are foolproof. Some plants such as gopher spurge (Euphorbia lathyrus) and castor bean (Ricinus communis) have been reported to deter gophers because they exude a poisonous substance from their roots. Research shows that neither of these are consistently effective repellents. Putting substances in gopher tunnels — used kitty litter, rags soaked in predator urine or pine oil — works for some gardeners. Ultrasonic noisemakers provide only short-term relief.
The most effective controls are exclusion and trapping. In small beds, gardeners can create cages or baskets to protect prized plants. Dig a 2- to 3-foot-deep hole in the planting area and line the sides and bottom of the hole with wire mesh. Replace the soil and plant your garden. Protect trees with wire mesh guards placed a few inches below the soil line and 2 feet up the trunk. If need be, use traps to kill problem gophers.
The use of poisons, particularly anticoagulant rodenticides, is not recommended, no matter how bad the problem! Gophers do not necessarily die in their burrows, and anticoagulant rodenticides can take up to 10 days to kill an animal once it has ingested a lethal dose of the poisons. Thus, predatory animals can easily be exposed to the poisons by preying on already poisoned (but not yet dead) gophers.
If you are interested in traps, click here to learn more about those options.
Although most people think of Bambi as a cute forest creature with retiring behavior, due to an growing population, deer have become a major garden pest throughout the country. Although they tend to keep to forest edges and fields grazing on grasses and leaves, they become more daring when food is scarce, venturing into suburban yards. Deer graze and browse leaves, stems, and buds of many woody plants, as well as alfalfa, roses, corn, vegetables, and fruits. Their damage is evident because they leave jagged leaf edges on the eaten plants, not to mention distinctive cloven hoof prints and bean-shaped droppings.
Although deer will eat anything if hungry enough, given a choice they tend to stay away from succulent plants, poisonous plants, pungent flavored plants, and plants with hairy or furry leaves. Plant ornamentals with these qualities in areas of heavy deer traffic. Some gardeners have had success using human hair, dog hair, soap, blood meal, rotten eggs, hot pepper, or predator urine spread around or on flowers and trees. Deer can be scared away by motion sensor devices attached to lights or loud music. Of all the methods, though, fencing is the most reliable. It’s best to erect the fence before Bambi has found your garden or yard.
JUST BECAUSE WE DON’T WITNESS IT…
DOESN’T MEAN IT ISN’T HAPPENING
Ialon, Havoc, D-Con mice and rat traps
Mechanism of Action: second-generation anticoagulant. Absorbed
through the gut and inhibits the vitamin K-dependent steps in the synthesis
of multiple clotting factors. Death usually occurs through gastric hemorrhage.
Metabolism: brodifacoum is retained in the tissues at high rates,
sometimes remaining in organ systems during the entire lifetime of an
exposed animal. In a study that measured the retention of radioactive
brodifacoum in the livers of single-dosed rats, 34% of the single dose is
found in the liver after 13 weeks, and 11% of the dose remained in the liver
for 104 weeks, approaching the normal lifespan of a rat (U.S. EPA MRID
Very highly toxic to mammals and birds.
Brodifacoum is extremely dangerous to birds through secondary exposure,
especially raptors feeding on poisoned rats and mice.
Hundreds of avian and other wildlife mortalities have been
reported across North America.
Brodifacoum is absorbed through the gut and works by preventing the
normal clotting of blood, leading to fatal hemorrhage. It is highly effective
at small doses – usually a rodent ingests a fatal dose after a single feeding
and will die within 4-5 days. The greatest risk to wildlife from brodifacoum
is secondary poisoning. Rodents continue to eat poisoned bait so at the
time of death the amount of brodifacoum present in their bodies is many
times the amount required to kill them. Non-target wildlife such as predators
and scavengers may then consume rodents that have ingested large
doses of brodifacoum. It can take as little as one poisoned rodent, or a
predator may accumulate enough brodifacoum after consuming several
poisoned prey items, to induce life-threatening or fatal effects. A single
dose of brodifacoum can depress blood clotting for months
in some animals, including birds. Stress or slight wounds incurred
in the fi eld, such as small scratches that normally occur when a raptorial
bird captures its prey, are often suffi cient to cause a fatal hemorrhage.
Raptor species maintain hunting territories that may include areas near
agricultural or other industrial and urban buildings where rodent control is
ongoing. Local avian predators may consume rodents living in and around
these structures. However, the death of such a predator will most likely
occur some distance away from treated sites, making it diffi cult to observe
patterns of mortality attributable to any one cause. Furthermore, birds that
have been exposed to lethal levels of brodifacoum may be more likely to
die from other causes such as accidents or predation. Most mortality undoubtedly
goes undiscovered. For these reasons, the true impact on birds of many pesticies,
including brodifacoum is obscured.
More on Pesticides:
1) Widely used pesticides are not particularly specific for the “target” organism. Such
pesticides can cause unintended and unwanted effects
to “non-target” resources. Species can be exposed to pesticides by many
routes, with the simplest form being direct contact or ingestion.
2) Animals can ingest pesticides indirectly through contaminated foods such as
leafy material, seeds, and prey (including insects and other animals), or by water contamination
through precipitation and irrigation (puddles, drinking water, bathing water or
3) Aquatic organisms can be exposed to pesticides entering water bodies through runoff
and groundwater infi ltration. Measurable amounts of pesticides have been detected in
4) Indirect effects of pesticides can also have signifi cant implications to animal species.
For example, herbicide drift can harm plants and consequently damage the habitat upon
which an animal species depends. A given pesticide can be relatively non-toxic to an
animal species, but may be lethal to its prey or food plants. Similarly, an insecticide can
indirectly harm an endangered plant that may depend upon a specifi c insect pollinator.
5) Wildlife, for example, are more susceptible to pesticide effects during nesting, nursing
of young or during times of low food availability.
6) Primary exposure includes eating, drinking, preening of feathers, skin contact
or breathing of vapors.
7) Secondary exposure occurs from scavenging on contaminated
food, such as exposed carcasses, or feeding upon insects. If pesticide
levels are high enough, wildlife often die suddenly.
8) Not as readily observed in wildlife are the sublethal, or
non-fatal, consequences of ingesting pesticides. Behavior
changes, weight loss, impaired or unsuccessful reproduction, high offspring mortality
or deformed embryos are results of sublethal exposure to pesticides. Affected wildlife
become easy prey for predators, while many lose their ability to adapt to environmental
9) Pesticides can reduce insects that may be important
food sources for young birds and fi sh, and habitat is similarly reduced
when vegetation is destroyed — a critical factor for small wildlife populations already
stressed by insuffi cient habitat.
Raccoon – Los Angeles
Diet: : Small mammals, birds, insects, trash,
carrion and fruit.
Coyote – Admitted with mange, Griffi th Park.
Diet: Small mammals, rodents, ground squirrels, carrion, berries,
fruit, vegetables and insects.
Screech Owl – Agua Dulce.
Diet: Small rodents and insects.
Greenback Heron – Simi Valley.
Diet: Fish, small mice and insects.
Grey Fox – Van Nuys.
Diet: Small rodents, birds, insects, fruit, berries and carrion.
When you attract deer to your property, you may also be attracting mountain lions.
More than half of California is considered deer habitat. And where there are deer, there are mountain lions. That’s because deer are the mountain lion’s primary prey.
Allowing deer access to your garden and landscaping, or intentionally feeding deer, can be deadly. Wild animals naturally fear people, keep a distance, and will not bother you, so long as they remain truly wild. But if they become accustomed to humans, their natural ways are ruined. Their normal wildlife and fear of humans is lost. That’s when conflict occur.
- Never intentionally feed deer.
- Landscape with deer-resistant plants.
- Enclose gardens with eight-foot fencing or use deer-proof fencing.
- Pick up fallen tree fruit.
- Install motion-sensitive lighting around the house and garden.
- Consider using commercially prepared deer repellents (available at garden supply stores.)
Wild Animals Ruined, Even Killed,
by People’s Carelessness!
Wild animals are in trouble, and the problem is people who are careless with food and garbage.
Coyotes play an important role in the ecosystem, helping to keep rodent populations under control. They are by nature fearful of humans.
If coyotes are given access to human food and garbage, their behavior changes. They lose
caution and fear. They may cause property damage. They might threaten human safety. They might be killed.
Relocating a problem coyote is not an option because it only moves the problem to someone else’s neighborhood.
Help prevent deadly conflicts for these beautiful wild animals.
“Coyote country” precautions
- Never feed or attempt to tame coyotes. The result may be deadly conflicts with pets or livestock, or serious injuries to small children.
- Do not leave small children or pets outside unattended.
- Install motion-sensitive lighting around the house.
- Trim ground-level shrubbery to reduce hiding places.
- Be aware that coyotes are more active in the spring, when feeding and protecting their young.
- If followed by a coyote, make loud noises. If this fails, throw rocks in the animal’s direction.
- If a coyote attacks a person, immediately contact the nearest Department of Fish and Game or law enforcement office.
Stash Your Food and Trash
Allowing coyotes access to human food and garbage is reckless and deadly.
Coyotes primarily hunt rodents and rabbits for food, but will take advantage of whatever is available, including garbage, pet food, and domestic animals.
- Put garbage in tightly closed containers that cannot be tipped over.
- Remove sources of water, especially in dry climates.
- Bring pets in at night, and do not leave pet food outside.
- Put away bird feeders at night to avoid attracting rodents and other coyote prey.
- Provide secure enclosures for rabbits, poultry, etc.
- Pick up fallen fruit and cover compost piles.
- Ask your neighbors to follow these tips.
Please respect and protect wild animals.
Keep them wild.
Stash Your Food and Trash
Bears and other animals are attracted to anything edible or smelly.
- Store garbage in bear-proof containers, or store garbage in your garage until pick-up.
- Keep food indoors or in airtight and odor-free containers.
- Put away picnic leftovers; clean BBQ grills.
- Keep pet food inside, and bird feeders away.
- Pick up fallen tree fruit as soon as possible, or protect fruit trees with electric fencing.
- Remove cosmetic fragrances and other attractants, including bird feeders and compost piles.
- Install or request bear-proof trash containers.
Bear Country Precautions
- Keep a close watch on children, and teach them what to do if they encounter a bear.
- While hiking, make noise to avoid a surprise encounter with a bear.
- Never keep food in your tent.
- Store food and toiletries in bear-proof containers or in an airtight container in the trunk of your vehicle.
- Keep a clean camp by cleaning up and storing food and garbage immediately after meals.
- Use bear-proof garbage cans whenever possible or store your garbage in a secure location with your food.
- Never approach a bear or pick up a bear cub.
- If you encounter a bear, do not run; instead, face the animal, make noise and try to appear as large as possible.
- If attacked, fight back.
- If a bear attacks a person, immediately call 911.
When wild animals are allowed to feed on human food and garbage, they lose their natural ways – often resulting in death for the animal.
Please respect and protect wild animals.
Keep them wild.
MOUNTAIN LION BIOLOGY AND BEHAVIOR
Puma concolor – Cat of one color
Puma concolor is listed in dictionaries under more names than any other animal in the world. There are at least 18 South American native terms, 25 native North American, and 40 English names for mountain lions. The species most common names are:
Mountain lion, cougar, panther, puma, painter, concolor, cat of one color, cat of many names, tyger, ghost walker, klandagi, cuguacuarana, leopardo, catamount, koe-ishto, ko-icto, and el leon.
The mountain lion is tan in color, with black tipped ears and tail. Adults weigh 80 to 180 pounds and stand two to three feet high at the shoulders. The length of an adult lion is 6 to 8 feet from the nose to the tip of the tail. The tail measures one-third of the lions length. Mountain lion kittens have camouflaging spots and rings around their tails.
Mountain lions are calm, quiet and elusive. They prefer areas with dense undergrowth and cover, and will leave an area where they perceive a threat. Mountain lions live solitary lives, spacing themselves across their habitat by marking and defending areas known as home ranges. Home ranges contain resources cougars need to survive: hunting areas, water sources, safe resting places, lookouts, and for females, safe places to raise young. Although lions are solitary unless mating or accompanied by their young, their territories will often overlap those of the opposite sex, and only occasionally overlap with those of the same sex. A males home range is generally larger than a females. The home territories of mountain lions can cover hundreds of square miles, depending on the availability of prey, time of year, and changes in the local vegetation.
An opportunistic hunter, mountain lions eat prey that is familiar and easily available. They hunt alone from dusk to dawn, taking their prey primarily from behind. Mountain lions primary prey is deer, but they also feed on wild hogs, raccoons, rabbits, porcupines, and birds. A mountain lion may kill a deer every one to four weeks. They often drag their kill to another area and then cover it with dry leaves, grass or pine needles known as caching to protect it from other animals and to reduce spoilage. A lion often returns to the kill several times to feed, for a period of three days to one week.
As one of North Americas largest predators, mountain lions play an essential role in maintaining the health of deer populations. Cougars often prey on the sick, weak, young, and old deer, which helps to control disease and keeps the deer herds strong. Also, they keep deer populations from growing too large or staying in an area for too long and over-browsing their habitat. Over-browsing can threaten native plants and also destroy important habitat for song birds and other animals.
Americas lion has roamed throughout the Americas for at least 50,000 years. From deserts to humid coast forests, lions live from sea level to snow-covered mountains. They once ranged from coast to coast and from South America into Northern Canada. Today, because of habitat loss and efforts to exterminate mountain lions in North America, sustainable populations exist in only 12 Western U.S. states, and the Canadian provinces of British Columbia and Alberta. A small population exists in the Black Hills of South Dakota, and an endangered population in the tip of Florida (the Florida panther). Mountain lions prefer areas with dense undergrowth and cover, and will leave an area where they perceive a threat. Research has shown that mountain lions often change their movement patterns to avoid human occupied areas, or areas where humans are most active.
Mountain lions are incredible predators with an adaptability to a wide variety of habitats and prey species.
Mountain lions can:
- bound up to 40 feet running
- leap 15 feet up a tree
- climb over a 12 foot fence
- walk many miles at 10 mph
- reach speeds of 50 mph in a sprint
Lions sense movement more accurately than they see detail. Seeing in pixilated mosaics, their wide angle and night vision is much greater than our own. A lions hearing is acutely sensitive, far beyond human range. Their ears move independently to pinpoint the source of sounds.
MOUNTAIN LION SIGN
Mountain lions are constantly roaming their territories in search of food, water and shelter, often walking more than 10 miles per day. This movement enables them to maintain territories large enough to sustain themselves, and for males it provides an opportunity to monitor and mate with the females whose territory overlaps his. As lions roam they leave sign of their presence in the form of tracks, scat and scrapes. Identifying lion sign is a much better indicator of the presence of mountain lions in an area than a sighting of the actual animal. The vast majority of mountain lion sightings from 75 up to 95 percent are cases of mistaken identity.
MOUNTAIN LION SOUNDS
Scientists generally divide the cat family (Felidae) into two groups, or subfamilies: Pantherinate, the large roaring cats, and Felinate, the smaller purring cats. The ability to roar depends on the structure of the hyoid bone, to which the muscles of the trachea (windpipe) and larynx (voicebox) are attached. Mountain lions (Puma concolor) are the largest of the purring cats.
Members of of the Felinae group (mountain lions, lynx, bobcat, margay, ocelot, and jaguarundi) possess the ability to purr or make shrill, high-pitched sounds.
Mountain lions are very vocal during mating. The caterwaul characteristic common in domestic cats seems to be even louder in mating mountain lions.
Lions have a distinctive M shaped pad, and their claw marks do not show in the track. Walking, the lions hind foot steps in his fore track, creating overlapping patterns. Cats usually walk through life; like their domestic cousins, they choose a very easy and deliberate walking pace with the result that their tracks typically appear clean and undisturbed, the animals weight showing in an evenly distributed impression.
Cougars will deposit their scat in the middle of trails and dirt roads as a territorial marking. Mountain Lion scat tends to be segmented. The presence of hair, bones and teeth is common. They can be over an inch in diameter.
Cougars will sometimes scrape together a pile of dirt or debris, leaving visible scratch marks in the ground, upon which they may urinate or defecate. This is another form of territorial marking.
Stop the painful poisoning deaths of wildlife, pets and people from Compound 1080 and sodium cyanide.
Compound 1080 and another deadly poison used regularly by Wildlife Services, sodium cyanide, are ranked Level 1 by the EPA for their “high degree of acute toxicity.” They’re meant to protect livestock from native predators. But other animals, including endangered species and pets like Bea, as well as people, often become accidental victims. A new bill, H.R.5643 would ban the use of these two indiscriminate killers.
Kept in rubber bladders and tied around the necks of sheep, goats, and cattle, Compound 1080 is meant to poison a livestock animal’s attacker when they rip open the bladder trying to take down the animal. But the pouch is also easily punctured by thorns, barbed wire, and other sharp objects — and this silent killer leaks into the environment for other unsuspecting animals to ingest.
Death from Compound 1080 — just one teaspoon of which is strong enough to kill 100 human adults — is especially agonizing. Animals who’ve ingested the poison have been found with vomited lungs, distended veins, and evacuated bowels and bladders. They’ve even been seen trying to rip open their own stomachs to get at the painful poison.
Likewise, sodium cyanide is an indiscriminate killer often mistakenly ingested by ill-fated animals and people. M-44s are spring-activated ejectors that are set off when a predator (or other animal, or child, or hiker…) pulls at the top, which is a discreet knob buried in the ground. The M-44 is meant to eject the poison into a predators mouth and face, and can spray the toxic granules up to five feet. Victims can die within minutes or suffer for hours.
It’s estimated that 12,000-15,000 animals die per year from M-44s ejecting sodium cyanide. This number doesn’t even include the number of pet victims. Past Wildlife Service employees have said that agents will remove collars of dogs and discard the bodies, for fear of jeopardizing its predator control program.
These extremely lethal poisons are under-controlled and, as a result, countless unintended species die. In 2007, Wildlife Services even admitted they were having internal issues with safely handling hazardous chemicals. And after two failed audits, the Office of the Inspector General reported “an alarming lack of inventory control and unrestricted access to poisons by unauthorized people.”
It’s outrageous that an agency named “Wildlife Service” would expose wildlife and other species to such an indiscriminately harmful toxicant. You can sign the petition to support H.R.5643 and stop the accidental deaths of wildlife, pets, and people from Compound 1080 and sodium cyanide.
Rodenticides can harm wildlife; please use carefully
Throughout California, the careless use of poison baits used to control rodents has injured and killed numerous wild animals and pets. This is because scavenging birds like owls, hawks, and predators such as raccoons, foxes, skunks and coyotes that eat dead or dying rodents that have consumed these baits will also be poisoned.
Pets will also eat dead or dying rodents and unprotected bait. You can protect both pets and wildlife by reading – and following – the label directions of any rodent baits you purchase, and only purchasing those that are legal for the pest you are trying to control.
Protect your wild neighbors and pets from accidental poisoning. Use all pesticides very carefully and follow all label directions, or chose organic or mechanical pest control methods.
Rodenticide Baits: Frequently-Asked Questions
Q. How do rodent baits harm wildlife and pets?
A. It’s possible for wildlife and pets to consume the poison directly. However, it’s more likely that these animals have received a secondary exposure. A secondary exposure occurs when wildlife or pets consume dead or dying rodents that have eaten the rodent bait. Wildlife that can be affected by secondary poisoning include owls, hawks, other scavenging birds and predators such as raccoons, foxes, skunks and coyotes.
Q. How can I protect wildlife and pets, but still control rodent pests?
A. Rodent bait users must follow label directions carefully. Some rodent baits, for example those that contain the active ingredients chlorphacinone and diphacinone, are legal to use in outdoor areas. These products can be used to control field rodents such as gophers, voles and ground squirrels. Other rodent bait products, such as those that contain the active ingredients broadifacoum, bromodialone or difethialone, can only be used to control rodents found within structures, like rats and mice.
- Read product labels carefully before using any pesticide, and follow directions exactly.
- Check daily for dead rodents. Wearing gloves, collect the carcasses as soon as possible, place in plastic bags and dispose in garbage cans with tight lids that other animals can’t open. Always wear protective gloves when handling any dead animal.
Q. Where can I get the rodenticide with chlorphacinone and diphacinone?
A. These products are sold at many hardware, nursery and farm supply stores. Depending on the county, they may also be sold by the county agricultural commissioner’s office.
Q. Why are chlorphacinone and diphacinone safer to use in open spaces?
A. Chlorphacinone and diphacinone are less toxic to mammals, and are eliminated rather quickly from the bodies of animals that ingest them. These products generally require multiple feedings before killing rodent pests.
Q. What kind of rodenticides should I NOT use in the yard, away from buildings?
A. Over-the-counter rodenticides, such as d-Con®, that contain the active ingredients brodifacoum, bromadiolone or difethialone. These can only be legally used to control rats and house mice in and around structures. It is illegal to use these products in open areas such as pastures or fields.
Q. Why is brodifacoum so dangerous for wildlife and pets?
A. Brodifacoum, bromodialone and difethialone pose a greater secondary toxicity risk to wildlife and pets than products that contain chlorphacinone and diphacinone. These products are more toxic to mammals, stay longer in the bodies of animals that ingest them and can kill with a single feeding. Their residues are most likely ingested by scavenging dead rodents. Deer are sometimes attracted to the pellet form of brodifacoum.
Q. How do these rodent baits work?
A. Both types of rodenticides are anti-coagulants. Animals that ingest them die from internal hemorrhaging (bleeding).
Q. How do you know rodent baits are poisoning wildlife?
A. Since 1994, DFG’s Pesticide Investigations Unit has confirmed at least 136 cases of wildlife poisoning from anticoagulant rodent baits. Brodifacoum was the poison most frequently detected. Animals harmed include coyote, gray fox, San Joaquin kit fox, raccoon, fox squirrel, bobcat, red fox, mountain lion, black bear, Hermann’s kangaroo rat, golden eagle, Canada goose, great-horned owl, barn owl, red-shouldered hawk, red-tailed hawk, Cooper’s hawk, turkey vulture and wild turkey.
Since animals typically retreat to their dens, burrows or other hiding places in the final stages of anticoagulant poisoning, the number of non-target wildlife killed by these compounds may be much greater than we know. DFG researchers have found that most birds and mammals killed by anti-coagulants are found in areas adjacent to urban development.
Q. Can I control rodent pests without using poison baits?
A. You can discourage some rodents from moving in by keeping grasses mowed at no more than two inches or by disking around sites that need to be protected. (See Vole Control, below.)
Q. I found a dead raccoon (or other small wild animal) in my yard. What should I do?
A. First, do NOT touch it bare-handed. Wildlife can carry diseases and parasites, so always wear protective clothing – especially gloves – before handling dead or dying animals of any kind. If you’re in an urban or suburban area, call your city or county animal control office with detailed information about the animal’s appearance and condition. Even if they don’t have the staff to come retrieve it, they need to know about it, as the one you found may not be the only one.
Q. If I think my pet has been poisoned, what should I do?
A. If your pet is having seizures, is unconscious or losing consciousness, or is having difficulty breathing, phone ahead and take your pet immediately to your local veterinarian or emergency veterinary clinic.
Rodent baits are often used to control voles. Their populations tend to be cyclical and once established, vole colonies are not easy to control.
One of the most effective ways to discourage voles from moving in is to simply mow grasses down to no more than two inches or disk around sites that need to be protected. Either action will reduce or eliminate their preferred habitat. Often, if you don’t control the vole population, there may be little you can do about it. The secret is to protect sensitive sites – such as gardens – by mowing or disking the area before the population gets too high.
If you must use a rodent bait to control voles, only use those baits intended for field rodents. Their labels will identify chlorphacinone or diphacinone as the active ingredient. Baits should only be used in small treatment areas and the areas should be checked daily for dead rodents.
With very high vole populations, rodent baits may ultimately have little effect. The best approach is to protect sensitive sites – such as gardens – by mowing or disking the area before the population gets too high.
Operating with permits from the California Department of Fish & Wildlife.