California Wildlife Center

Wildlife Nuisances

California Wildlife Center is primarily concerned with the rescue, rehabilitation and release of injured, sick and orphaned wildlife. However, we do get frequent calls from people who have problem situations living alongside what they consider to be problem animals. How do you stop raccoons tipping your trash can, skunks digging up your lawn or swallows nesting in your roof? If you have similar questions, this is your page. You can email your comments about this page or suggestions for new topics to admin@californiawildlifecenter.org. You may also want to consider the following resources:

• Westerman, Martin D. "Dealing Successfully With Urban Wildlife." The Business Environmental Handbook. Seattle: The Oasis Press, 1993.
• Stahl, Greg. "Where Rugged Dreams Meet Nature's Realities." The Idaho Mountain Express, November-December 1998.
• The University of California at Santa Cruz's website.

Biologists call species such as raccoons, skunks, and swallows, "generalists." They are adaptive and have taken advantage of the new urban habitats we have created and often come into conflict with our lifestyle. On the flip side are the "specialists" which can only survive in a narrow range of environmental conditions. These animals are often endangered by human encroachment on their habitat.

The following information will help you coexist with some of those generalist species that might currently be a nuisance to you, without harming the animals. You can search for tips by species or situation.

Problem Situations

Garbage Cans:

Rummaging through trash cans is the most common wildlife problem. Not only is it a mess for humans, it is unhealthy for wild animals to eat human food and refuse. Keep trash inside as long as possible, put it outside only on trash day, and put it out in the morning, not nighttime. Keep lids on properly, store trash and trash cans in animal-proof metal containers; install a motion sensor near cans that will switch on a floodlight to frighten nocturnal visitors.

Nesting/Denning:

Birds and small mammals are pretty resourceful here. If you would like to thwart nesting or a den: first allow the present occupants to complete their nesting/nursing cycle and leave the nest/den, then barricade or alter the area, block the hole, mend the screen, remove the woodpile, block the eaves, etc. If you would like to thwart roosting: change the roosting surface to 60 degrees, install porcupine wire or slinky toys, block eaves, use effigies (of owls, for example) and other scare devices (aluminum foil, aluminum ribbon).

Supporting nesting and den habits doesn't require much "maintenance" unless a nest gets knocked down. Just repair it and put it back!

There are many ways to reduce the probabliity of a problem in your area, mainly by blocking access to sources of food and water:

• Small mammals (skunks, ) may feed on human refuse. Maintain garbage cans properly; make sure they're out only on trash day, that they are brought out in the morning, and that your lids are securely fastened.
• Small mammals (skunks, ) may dig up gardens and lawns in search of grubs. Biological nematodes will kill the grubs and insects in gardens and lawns, hence getting rid of the skunk food source. Sprinkling cayenne pepper is also effective.
• Don't use fish-based fertilizer on lawn or plants. Don't scatter food for birds on the ground — use a feeder.
• Remove brush piles, wood piles, and compost piles.
• Block openings that lead to shelter. Replace vent covers and fill holes that lead under building. You can cover openings with 1/4" hardware cloth, make sure it extends 6 to 12 inches to prevent digging underneath. Caution - be sure that the animals are gone before you seal up any holes! The best time to plug up holes (and avoid sealing up babies) is September through March (skunks).

Gardens and Lawns:

If you would like to deter animals such as deer and rabbits from trees, shrubs or veggies, hang bags of human hair or nylons from the branches or near the plants. Adequate fencing is a "must" deterrent for deer. Fences should be at least 8 feet high and slanted toward the approach side; if skunks and raccoons are tearing up your lawn, rid the lawn of grubs. A good repellent for moles and hedgehogs in your lawn is an old sweat sock, stuff it down their burrow. Sprinkling cayenne pepper to make areas unattractive can also be effective. Avoid using fish meal based fertilizers. Use a bird feeder, sprinkling bird food over the lawn will invite other animals to join in.

If you want to support a species, find out what they eat and plant it. Provide seeds and fruit bearing trees or bushes for birds. Remember, however, if you provide seeds one season, you must provide them the next, birds learn to rely on them!

Ponds/Pools:

These items will often attract waterfowl and animals searching for water to drink. If you would like to deter animals from drinking the chlorinated water from your pool, or would like to thwart waterfowl altogether, run your pool-cleaning unit, or get a solar powered toy boat and set its rudder to sail in circles.

Pets:

It is best to keep your pets, livestock, and chickens inside or in predator-proof enclosures as often as possible, especially at night. Predators such as coyotes and some raptors are opportunistic feeders and will prey on domesticated animals. Also, a vast majority of injured wild young (birds and mammals) are "cat caught," so please keep your cat indoors as often as possible.

Remember, never hand-feed wild animals (or feral cats) and avoid handling them (especially if they appear to be sick) — contact a professional. Never place yourself between a wild animal mother and her babies, and never corner a wild animal.

Problem Animals

Bobcats:

Healthy bobcats are usually not an immediate threat to humans; they are only about the size of cocker spaniel and their main prey (rabbits and rodents) are quite small. However, it's a good idea to keep small pets indoors and small children shouldn't be left unattended.

Mountain Lions:

Mountain Lion sightings in the Santa Monica Mountains are very rare. Most people have actually seen a bobcat, deer, domestic cat, or coyote when they think they've sighted a mountain lion. However, if you believe you've seen a Mountain Lion, report it immediately to the Department of Fish & Game at (916) 445-0045.

For tips on what to do if you encounter a Mountain Lion while hiking, and for information about pumas, see the Mountain Lion Foundation's website at: www.mountainlion.org

Coyotes:

Due to the rapid loss of habitat from commercial & residential development, many coyotes have found themselves forced to cohabit with humans. This cohabitation if facilitated by the fact that coyotes adjust rapidly to changes in their environment. Yet coyotes fill an important role in the natural world, especially by keeping in check the numbers of rodents, rabbits, and other small animals that share their habitat.

Attempts to relocate coyotes away from pupulated areas have often met with failure. Coyotes have survived hunting, trapping, shooting, poisoning, extermination by ranchers, and other attempts of eradication. Among the facts bearing on this phenomenon are:

• Coyote pups, although weaned at an early age, may remain with their mother into their second year, often helping the mother care for her newest litter.
• Disruption of this "pack" can mean devastation for the whole group or cause disoriented or suddenly orphaned coyotes to deviate from the norm and prey on easy game (small dogs, rabbits, cats, chickens, etc).
• The coyote's reproduction level appears to be directly correlated to attempts to control its population — larger litters seem to be born in areas where intensive efforts at extermination or control have been undertaken.
• If coyotes in a certain area are killed or relocated, the remaining coyotes will fill the vacancies, either with larger litters or by allowing outsiders to move into the area.

There are many ways to reduce the probabliity of a problem in your area, mainly by blocking access to sources of food and water:

1. Do not leave pet food outside or feed pets outside.
2. Keep small pets indoors; but if you must let them out, bring them inside at dawn, sunset, and night, when coyotes are most active.
3. Eliminate outside sources of water.
4. Position bird feeders so coyotes can't get the feed. Coyotes are attracted by bread, table scraps, and even seed. Birds and rodents that come to the feeders also attract coyotes.
5. Put chickens and livestock in predator-proof enclosures.
6. Erect walls and fences where you can, at least 6 ft tall, and 6 inches below ground.
7. Install a Coyote Rail Roll Guard that makes it difficult for dogs, coyotes, and other animals to gain the foothold they need to pull themselves up and over the top of an enclosure.
8. Clear brush and dense weeds from around dwellings. Reduce protective cover for coyotes and make the area less attractive to rodents. Coyotes, as well as other predators, are attracted to areas where rodents are concentrated, such as woodpiles and seed storage areas.
9. Cover compost piles, or use compost bins.

Bats:

If you want to exclude bats from your attic, find the hole where the bats are coming and going and attach a piece of netting as a flap on the outside which is left loose on the bottom. The bat will be able to get out but not get back in. Also, when the bats are out foraging, you can soak the area with dog repellent or ammonia. Be careful not to separate a mother from her babies. In this case, wait a few weeks until the babies are flying before excluding them. Blocking access should occur from mid-August to late May. This is when the babies have been weaned and are able to fly.

If you find a bat in a building, it is best not to attempt to catch it. Instead, isolate the area (close doors), but leave a window open, the bat will usually find its way out. If catching it is the only option, and the bat is on the ground and appears to be healthy, use the following technique. Wearing heavy leather gloves, you can place a large jar or coffee can over it, and then slide a piece of cardboard underneath the jar or can, and release it outdoors. If the bat appears to be sick, then do not touch it, as bats can be rabies carriers. Contact a professional (e.g. an Animal Control Officer). If you are bitten by a bat, make sure you save the animal for examination. Wash the wound immediately with soap and water and see your doctor immediately.

If you would like to support this beneficial creature properly, you may wish to install a bat box. Bat houses can be purchased through gardening catalogs. The bat house must be at least 12 to 15 feet above the ground, and placed where it will receive morning, but not afternoon, sun (they cannot tolerate temperatures above 90 degrees). Bat houses should be installed near a water source (marsh or pond) where a healthy insect population is likely to exist.

Skunks and Raccoons:

The public should not handle skunks or raccoons. They can carry rabies and leptospirosis and are very aggressive animals. With a few simple tricks (see Problem Situations: Nesting/Roosting/Denning: above) to discourage them from hanging around, they should leave within 24 to 48 hours. It will take longer if young are involved as the female must find a new home for them. Trapping and relocating is discouraged, because they are urban animals and will probably come back unless the food and shelter source is removed.

Deer:

If you have trees and shrubs that you want to protect form foraging deer, you may want to:

• Erect fencing, at least 8' high.
• Hang bags of human hair in trees and shrubbery
• Errect effigies (these work for a while, but they must be moved almost daily because deer habituate to them quickly and no longer see them as a threat).

Feral Cats:

Do not feed feral cats. Eliminate woodpiles, as well as access to old abandoned buildings, sheds, etc. Keep backyard vegetation trimmed, as it provides cover for them.

Rodents:

Prevention is the best method, if you don't give rodents a reason to come into your yard, you lower the possibility of them getting into your house:

• Eliminate outside water sources (pet bowls, ponds, etc.)
• Secure garbage in containers with tight lids.
• Keep bushes at least 3 feet from the house.
• Don't feed pets outside.
• Clean up birdseed on the ground.
• Pick up fruit, nuts, and vegetables.
• Take junk to the dump.
• Keep any pet food/bird seed stored outside in a metal or heavy plastic container with a tight lid.
• Pick up pet waste- rodents will eat this!
• Eliminate brush, wood, and rock piles.
• Trim tree branches that hang over your roof.
• Install a spark arrester (chimney cap) on chimney or cover with a ¼" hardware cloth.
• Seal all openings into the house greater than ¾ inch. Openings may be around utility lines, air conditioner, drainpipes, or vents. Seal them with metal, hardware cloth, mortar, or concrete.
  • Mice can squeeze through ¼ inch openings
  • Rats can squeeze through ½ inch openings
• Rats can also come through your pipes, so run your disposal regularly to clear away food and clean it at least once a month. Pour in one cup baking soda, followed by one cup of white vinegar — it will foam. Follow with hot water.