Raccoons Roost in Roofs and Raid Gardens in Utah
Friday, May. 31, 2013
Extension Wildlife Specialist
Utah State University
Phone: (435) 797-3975
RACCOONS ROOST IN ROOFS AND RAID GARDENS IN UTAH
LOGAN – Raccoons, found in abundance throughout much of Utah, are most commonly found in wooded areas along rivers, marshes or lakes. In urban areas, they make their dens in attics, chimneys, under houses, in abandoned buildings and in woodpiles.
According to Terry Messmer, Utah State University Extension wildlife specialist, raccoons are opportunistic and seek a lifestyle that has the greatest reward for the least amount of effort. Urban environments often provide such opportunities, and raccoons are quick to adapt.
“Most towns and cities in Utah have raccoons living within city limits,” Messmer said. “Because they are active at night, they are seldom seen. Of all the wild animals that have adapted to city life, raccoons are probably the most destructive. Extension and resource agency professionals estimate they cause 60 to 70 percent of all urban wildlife problems in Utah.”
As raccoons lose their fear of humans and take up residency in urban areas, they feed in garbage cans, make dens in chimneys and plug them with nest material, tear off shingles or fascia boards to enter an attic or wall space and cause damage to gardens and fruit trees. They may also carry fleas, ticks, lice, distemper, mange and rabies as well as canine and feline provirus. Recent blood tests on raccoons in Utah showed that more than 80 percent had been exposed to rabies.
Messmer said another concern is that raccoon feces may contain raccoon roundworm. Humans, especially children, who come in contact with raccoon feces containing roundworm eggs can become infected. Clinical symptoms depend on the number of roundworm larvae present in the body and their location. If the larvae migrate to the eyes or brain, blindness or death can result.
Raccoons can also threaten the health of other mammals. They can carry Aleutians disease, a virus that affects other fur-bearing animals and poses a major threat to Utah’s fur industry. In addition, raccoons entering the buildings where mink are raised may eat off the minks’ feet through the wire mesh in the bottom of their cages. The injured mink usually die soon after injury.
Raccoons also cause problems in rural areas by raiding chicken coops or poultry farms and killing many birds but only consuming some. Damage to agricultural grain crops and predation on bird nests are other common problems.
A female with young may attack if cornered, so Messmer said to be cautious if a mother and young are encountered in an enclosed space. Since they may attack humans, raccoons should not be kept as pets, especially if there are small children in the house who could not defend themselves.
“Raccoons are not protected under Utah state law, so no hunting or trapping license is required to take them,” Messmer said. “However, Utah state law prohibits possessing a live raccoon without a permit. Permits come through the Utah Department of Agriculture if justification is provided.”
Raccoons in a chimney or attic may whine or growl. They may also damage gardens or fruit trees, as evidenced by remains of partially eaten fruit, and will pull over cornstalks, then partially husk the corn before eating it off the ear. They can also damage melons by digging a small hole in the melon and hollowing out the contents.
“Raccoon activity is identified by distinctive tracks,” he said. “The hind print is 3 1Ž4 to 4 1Ž2 inches long, much longer than wide, and the fore print is shorter, about 3 inches long, and as wide as long. The distance between prints of a walking raccoon is about 14 inches, with the left hind foot almost beside the right forefoot. Five toes and claws are visible on each foot. Skunk tracks are smaller, with the hind print 1 1Ž4 to 2 inches long and the fore print 1 to 1 3Ž4 inches long. Flour may be spread at damage sites to reveal tracks from activity during the night.”
Once it has been determined that a raccoon is causing damage, several things can be done, including habitat modification, exclusion, the use of chemical repellents and population reduction.
Exclusion, if feasible, is usually the best way to handle raccoon damage, Messmer said. Raccoons can be kept from poultry with tightly covered doors and windows on buildings or mesh-wire fences with an overhang surrounding poultry yards. Raccoons can gain access by climbing conventional fences or by using overhanging limbs to bypass the fence. A “hot wire” charger at the top of an electric fence will greatly decrease the chances of a raccoon entering.
Damage to corn and watermelon can most effectively be stopped with a single or double hot-wire fence that can be turned on in the evening before dusk and turned off after daybreak. Electric fences should be used with care and have appropriate caution signs installed.
Wrapping filament tape around ripening ears of corn or placing plastic bags over the ears is an effective method of reducing raccoon damage to sweet corn. In general, tape or fencing is more effective than bagging. When using tape, apply the type with glass-yarn filaments embedded so raccoons can’t tear through it. Taping is more labor-intensive than fencing, but may be more practical and acceptable for small backyard gardens.
Store garbage in metal or tough plastic containers with tight-fitting lids to discourage raccoons from raiding cans. If lids don’t fit tightly, it may be necessary to wire, weight or clamp them down. Secure cans to a rack or tie them to a support to prevent raccoons from tipping them.
Messmer said to prevent raccoon access to chimneys, fasten commercial sheet metal and a heavy screen over the chimney top. Raccoon access to rooftops can be limited by removing overhanging branches and by wrapping and nailing sheets of slick metal at least 3 feet square around building corners.
“This prevents raccoons from being able to get a toehold for climbing,” he said. “While this method may be practical for outbuildings, it is unsightly and generally not acceptable for homes. It is better to cover chimneys or other areas or to remove individual animals than to completely exclude them from the roof.”
It is important to be sure all raccoons have left the area before using exclusion procedures, Messmer said. They will frequently enter uncapped chimneys and raise their young on the smoke shelf or the top of the fireplace box until weaning. Homeowners with the patience to wait out several weeks of scratching, rustling and chirring sounds will be rewarded when the mother raccoon moves the young when she weans them. Homeowners with less patience can contact a pest removal or chimney sweep service to physically remove the raccoons. In either case, remember to use exclusion procedures immediately after the animals are gone.
For more information on dealing with roving raccoons, contact your local USU Extension county office or visit extension.usu.edu/files/publications/publication/nr_wd_002.pdf.