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Keep Wildlife From Moving In With You

Published on: 2/17/2015 10:52 AM

Santa Clara County, developed from a farming community to 15 large cities and unincorporated areas, is home to many types of wildlife. These animals, which include rodents, squirrels, opossums, raccoons, foxes, skunks, coyotes, deer, bobcats and mountain lions, may prowl your neighborhood both day and night in search of food and harborage (shelter). “Urbanized” wildlife have modified their behavior, becoming less “wild”. This change increases the chances of interaction with humans and pets, thus raising the potential for danger and problems. The abundance of food (garbage, pet food, even PETS) and shelter (homes, decks, out buildings) in urban areas, has reduced the animals normally large home-range area. These “urbanized” animals have learned to depend on man for food and shelter and often pass this behavior on to their young. As beautiful and fascinating as wildlife may be in their natural environment or when they pass through our yards, it is important to remember they are wild. It is unfair to create conditions that encourage them to stay/live with us. Fear of humans is their most important survival tool. Loss of this fear, or a tolerance of humans and their pets, can and does create damaging and dangerous situations; not only for us and our pets, but the wildlife themselves.

The following information, which focuses on prevention, will help you discourage rodents, squirrels, opossums, raccoons, skunks, deer, coyotes, bobcats and mountain lions from depending on you for survival and moving into you house or yard.


  • rodents need only a ½ inch opening to gain access into your home
  • animals such as skunks, opossum, and raccoons only require a hole large enough to get their head through to gain access into your home, garage, shed or decks
  • electrical fires, damage to central heating systems, structural damage, flooding and other plumbing problems are often caused by rodents (squirrels & rats) and wildlife such as opossums, and raccoons
  • diseases carried by wildlife and rodents can be transmitted through feces, urine, and ectoparisites (fleas, ticks, mites, etc) as well as direct contact


Ripe and overly ripe fruit and vegetables, and nuts are strong attractants, as well as a favorite food source, to wildlife. To minimize the likelihood that wildlife will consider your yard or home as a permanent place to live, harvest all nuts, vegetables, fruit and citrus when ripe. Do not forget to pickup the produce that falls and/or rots on the ground.

Other yard and garden maintenance tips:

  • circle gardens and fish ponds with an electric dog fence to deter rodents and wildlife from raiding your garden area and fish pond
  • remove the dead growth from yucca plants and palm trees to keep rodents & wildlife from nesting in these areas. Trim and maintain woody ground cover such as ivy.
  • keep trees cut back 3-5 feet from your roof and 3 feet below eves to prevent rodents and other climbing animals from using them as a ladder to access your roof and attic area.

When lawns and other vegetation are over watered, worms and other insects come to the surface. Raccoons, opossums and skunks eat these insects and can cause serious damage to lawns and flowerbeds. Do not water late at night or before 7:00 am. Watering after 8:00am will allow the ground to absorb the water and dry, thus not leaving the soil soft and easily torn up by these animals.

Rain gutters and climbing vegetation planted next to house may provide access to the roof. Be sure to keep vegetation trimmed back or short.


Bird feeders feed more than just the birds and squirrels. Rodents will visit the feeder at night as well as their predators (i.e. opossums and raccoons). We strongly recommend removing bird feeders. But if you insist on feeding birds & squirrels, fill the feeder with only the amount they can eat in half a day or bring the feeder in at night. Make sure to clean up spilled feed every night.

Skunks, raccoons and opossums find pet food very appetizing. Do not feed pets outdoors. If feeding indoors is impossible, feed only the amount the animal can eat at one time. Remove all pet food and dispensers by 4:00 p.m. Removing food eliminates an attractant as well as helps prevent disease transmission, confrontations, and severe injury between pets and wildlife.

Garbage cans, recycle containers, and compost piles can be a continual source of food for rodents and wildlife. Keep compost piles covered and turn regularly. Remember to keep compost piles as well as garbage cans and recycle containers securely covered and maintained. This may even include locking the lids shut with a chain.

To prevent raccoons from eating expensive fish (i.e. Koi) encircle ponds with an electric pet fence. Be sure to follow manufactures directions and precautions.

City and county ordinance leash laws prohibits animal from running at large off the owner’s property. Confining your pets will help prevent them from becoming part of the food chain for the larger predators such as coyotes, bobcats and mountain lions, which are occurring with greater frequency in our semi-urban communities.


Remove all harborage such as trash piles and debris in which rodents and other wildlife may nest. Improperly stacked woodpiles may provide harborage for rodents and wildlife. Stack firewood 18 inches off the ground and a foot away from any structure.


  • Over-lapping roof-lines(where two roof planes meet or over-lap, an opening of ½ inch x 2 inch to 6 inch x16 inch frequently occurs), leading directly into the attic or garage): FIX: Seal area with ¼ inch hardware clothe and/or stucco. Also seal around metal flashing
  • Shake, tile and metal roofs placed over existing roof: FIX: The 1st choice is not to do this. Old shake roofs tend to curl with age and expose the tarpaper below. Rodents and wildlife will gnaw or tear through the old roof to gain access to the attic. The openings along the ends of a tile provide rodents & wildlife with harborage (shelter) as well as allowing access to attic. Seal the ends of tile with bird stops, stucco or cement. A metal roof over an existing roof is a serious problem since it provides a large air space for nesting. It is almost impossible to completely seal since there are so many openings.
  • Chimneys: FIX: To prevent chimneys from being used as nesting areas and entry points, install spark arresters and seal any openings where chimney passes through the eves of the roof.
  • Garage and side doors: FIX: Install weather-stripping to garage doors and side doors to prevent rodents from gaining access to house or garage.
  • Sheds and decks: FIX: Follow foundation recommendations.
  • Patio covers: FIX: To prevent wildlife from nesting between the area where the patio and house roof overlap, close off both ends of the patio cover with ¼ inch hardware cloth and stucco.
  • Pipe and wire entrances: FIX: Any gaps large than a ½ inch ( ¼ inch to exclude mice) needs to be filled in or covered. This can be done using 16 or 20 gauge ¼ inch hardware clothe, sheet metal, or cement fill. Your local phone and cable service may be able to install rodent stops to your lines.
  •  Attic and crawl space vents: FIX: Do not allow vegetation or tree limbs to come within 2-3 feet of vents. When possible, don’t allow wires, cables or plumbing to pass through vents. Damaged or cut vents allow wildlife and rodent access to under the house, attics and wall voids. Existing openings around wires or plumbing can be sealed with stucco. Replace standard vents with galvanized louvered vents to prevent skunks, raccoons and opossum from moving in.
  • Crawl space access areas: FIX: Keep these maintained with doors tightly sealed and secure to prevent rodent and wildlife access.
  • Dryer and stove vents: FIX: Screen ends and/or bottom of vents with ¼ inch hardware cloth.
  • Foundations: FIX: Remove all soil 6-8 inches below and 1½ feet out from the foundation wall. Attach ¼ inch hardware cloth to the side of the foundation wall, run it down the 6-8 inches below and, with a 90 degree bend in the wire, and 1-½ feet out from the foundation. Then replace soil. When building a new home or remodeling, please be sure your contractor understands how to make your home rodent/vermin proof. Also have them check to be sure utility hook-ups (i.e. electrical, cable, phone service, etc.) are properly sealed.