FOX SQUIRRELS AND THEIR CONTROL
Fox squirrels (Sciurus niger) are about 18 to 28 inches long from nose to tip of tail. They weigh about 1½ to 3 pounds and are a rusty yellowish brown color, with a large bushy tail.
Fox squirrels are active during the day, with most activity occurring in the early morning and late afternoon to early evening. They do not hibernate and are active year around. They breed December through January and June through July. Three to six blind and naked young are born in February to April and August to September after a 42 to 45 day gestation period. Newborn squirrels weigh about one-half ounce and open their eyes after about 32 days. Young begin exploring outside the nest when they are weaned at 10 to 12 weeks of age.
Squirrel populations periodically rise and fall and are intricately linked to the quantity and quality of available habitat. They have a high reproductive and death rate, with more than 50% of the squirrels in a population normally dying each year. They are a favorite food of many predators including hawks, owls, snakes, foxes, house cats and dogs. Squirrels are also susceptible to a variety of parasites and disease, including ticks, mange mites, fleas, and internal parasites. Most squirrels in the wild never reach four years old, but can live as long as 12 years in urban areas.
Fox squirrels feed on a variety of nuts, acorns, tree buds and seeds, corn, soybean, bird eggs, and cambium layer below the bark of small tree branches. They will ready feed out of trashcans and dumpsters in the city. Squirrels naturally nest in the cavities of trees or build nests of leaves, twigs, and bark high in the crotch or branches of trees. They see homes, with access to attics, as some kind of funny looking tree with a nice cavity, and will readily take up residence.
A survey of the National Pest Control Association voted the tree squirrel as the number one nuisance animal in the United States. They can cause a variety of problems, including damage to trees, flowers, lawns, gardens, vehicles and homes. They eat acorns, nuts, fruit or vegetables in home gardens and become a nuisance at bird feeders. Squirrels can cause extensive damage to attic insulation or walls and gnaw on electrical wires in homes and vehicles, creating a fire hazard.
At bird feeders, tree squirrels consume birdseed and suet, disrupt the bird feeding there and gnaw on the feeders. Squirrels that are allowed to congregate at bird feeders also can spread sarcoptic mange among themselves. Avoid hanging bird feeders from trees. Instead, use a large-diameter metal pole and baffle to elevate the bird feeder at least 5 feet off the ground. See the figures below.
Diagram (1) The metal baffle looks like a large dunce cap. Hang the bird feeder by a chain from an arm of the pole and place the baffle over it.
Diagram (2) Alternatively, metal flashing or stovepipe can be placed on the pole below platform feeders.
Bird feeders also can be hung from a horizontal wire with plastic pipe sleeves as protection on either side.
Evidence of fox squirrels inside the attic include noise from gnawing or running during the day, droppings, gnawed holes, leaves, twigs, shells, halls, pits, or nesting materials inside an attic. Squirrels can squeeze through holes 1½ inches in diameter or gnaw through smaller holes to gain access to buildings. They can climb vertical brick or masonry walls that have a roughened surface. They can enter through vents, chimneys, broken windows, knotholes and construction gaps under eaves or gables. Squirrels most often enter attics and spaces between walls and floors.
The best long-term solution to managing squirrel problems in the home is to exclude or "build them out" of a building or attic. Because squirrels are rodents and have large front teeth, you must use ¼ or ½ inch hardware cloth or 26 gauge metal when excluding squirrels from buildings. Do not use steel wool or window screening; the squirrels can chew through it. Look for openings under eaves, unscreened attic vents, loose flashing around chimneys and pipes, and openings around cables. Be sure all squirrels (including babies) are out of the attic before sealing all openings.
If babies are involved, any humane eviction should be delayed until the babies are old enough to leave the nest and survive on their own. Squirrels will often leave attics in the summer because the attic becomes too hot. You can wait until the hottest part of summer (July, before the second litter is due) and block the holes then. If there are no babies involved, pick a mid-morning on a warm sunny day to seal openings, as this is when squirrels are usually out eating. Check to make sure the squirrels, including any possible baby squirrels, are out before starting. Seal the openings, then spray the area with ROPEL, a proven repellent (available at garden, hardware, pet, or feed stores). Or you can use 1 tablespoon of TABASCO sauce to 1 quart of water, mix in a spray bottle
or apply with a paintbrush.
If a squirrel is accidentally stuck in the attic or you can not wait for it to leave, you can capture it with an 18x7x7 inch or larger live trap such as the Havahart or Tomahawk baited with peanut butter or nuts. They can be released (5 or more miles away). No toxicants or fumigants are registered for fox squirrels in Colorado.
Squirrels may temporarily vacate an attic and give you enough time to seal entrances if you place mothballs correctly throughout the attic. Use one pound of mothballs per 100 square feet of attic space. Because the mothball vapors are heavier than air, they must be suspended in baseball-size clumps close to the damaged area. Using old pantyhose is an inexpensive, effective way to do this. Beware the vapors from the mothball may also penetrate into the living part of the home, so should be removed as soon as possible.
To prevent further damage, trim all trees that have limbs within eight feet of the building. Squirrels can be discouraged from climbing trees if you put a band of two-foot-wide sheet metal around the tree about six feet up from the ground. The edges of this collar should overlap and be connected by springs to allow for the tree to grow. Remove any branches less than six feet from the ground to prevent squirrels from jumping onto them. If squirrels are gaining access via telephone or electrical wires, put a two-foot section of lightweight 2 to 3 inch diameter plastic pipes over the wire by slitting the pipe lengthwise and placing it over the wire. Be careful not to touch the wire. The pipe will rotate on the wire causing squirrels to tumble.
Trapping and relocation of squirrels is not recommended as a solution. Since squirrels are territorial, your squirrels will also keep other squirrels out of the area, keeping the population to minimum. If you remove the squirrels, others will simply move in and your problem continues.
To get help removing squirrels and sealing your home, you can call an animal relocater. Check the yellow pages under Pest Control and find a company that does wildlife removal.