Raccoons are one of Iowa's most adaptable and ubiquitous species, living right alongside humans in rural and urban communities. Occasionally this close proximity leads to conflicts between people and raccoons.
Habitat selection: Stretching from the tropical humidity of Panama to the frigid expanses of central Canada, raccoons occupy habitats as varied as coastal rainforests, desert scrub, mountain meadows, prairie-pothole marshes, deciduous woods, agricultural fields, and city parks. Therefore, it should come as no surprise that this mid-sized mammal is thriving in just about every terrestrial habitat that Iowa has to offer.
Diet: Raccoons are omnivorous, feeding on a wide range of items, such as nuts, berries, insects, worms, birds, eggs, rodents, rabbits, fish, crayfish, and clams. This varied diet allows raccoons to thrive near human habitation, where they consume sweetcorn, melons, and other fruits from gardens, scavenge for discarded food in dumpsters and bins, or dig up insects in yards.
Behavior: Raccoons are active mostly at night and around dawn/dusk. Superb climbing skills allow raccoons to access natural denning sites on big, sprawling trees and make them equally adept at scaling buildings to reach chimneys and other alcoves. Strong, dexterous “fingers” enable them to rip corn from stalks, extract food from dumpsters, dig pet food out of bins, roll up turf in search of grubs, and many other curious, adaptable feeding behaviors.
Iowa yards and farms offer ideal opportunities for raccoons
Shelter: Chimneys, attics, upper reaches of sheds, and tree cavities provide reliable protection from the elements and ideal places for raccoons to give birth and raise young. A study of raccoons in wooded suburban habitats of New England found that female raccoons actually prefer chimneys to trees during the first 1-2 months after giving birth and often return to favored sites in successive years.
Food: Pet food, wild birdseed, garden fruit/vegetables, and leftovers in garbage receptacles all serve as a steady source of nutrition for raccoons around human dwellings year-round. Research projects across multiple states, including those with landscapes similar to Iowa, have shown that such resources often help raccoons to maintain higher, more stable populations in towns than in natural environments.
Safety: Farmyards, towns, and suburbs further appeal to raccoons because these areas typically have fewer natural predators than “wild” habitats.
The raccoon’s close association with human-altered landscapes is further reflected in its mortality sources, at least in Iowa. For instance, during a study conducted on radio-collared raccoons in Guthrie County during the 1980s, almost 90% of all raccoon deaths resulted from human activities like hunting, trapping, and collisions with vehicles. Natural events such as disease and predation thus accounted for only a tiny proportion of mortality.
Signs that you have raccoons on your property
- Tracks: distinctive forefoot and hindfoot prints around gardens, dumpsters, and buildings
- Smudges: paw prints and smearings on sides of buildings, often most noticeable on downspouts
- Sounds from adults: harsh screeching during mating season (mostly in late winter and early spring)
- Sounds from young: chirping noises coming from denning spots like chimneys and tree hollows in spring and summer
One of the places where prints are most obvious is around patches of sweetcorn, which raccoons notoriously target. Any time you find raccoon tracks along your garden during sweetcorn season, you’re also likely to see the damage: partially eaten ears of corn with the husks ripped back and stalks broken in multiple places where the raccoons reached for the corn. Throughout the warmer months, you may also find other garden plants, like cantaloupe, showing holes where Raccoons have dug in and torn out the fleshy contents of the fruit.
Reducing damage caused by raccoons
Like all unwanted intruders in the home or on the farm, exclusion is the first line of defense against raccoons. Because they’re expert climbers and adept at using tree branches and other structures to gain access, a simple fence around your garden is often not enough.
Raccoons in sweetcorn
Partially eaten ears of corn with the husks ripped back
Stalks broken in multiple spots where raccoons reached for the ears of corn
Distinctive tracks in mud around corn patch
Install a two-wire electric fence, available at most farm-supply stores. Target raccoons (nocturnal) and maintain safety for people (daytime) by turning the fence on at dusk and deactivating it around sunrise.
Use filament (or tape that has filament embedded in it) to wrap the ears and anchor them to the adjacent stalk. Make sure to loop the filament/tape back over itself multiple times to keep raccoons from tearing through.
Trapping problematic raccoons.
Raccoons preying on domestic poultry
Raccoons first attack poultry by grabbing and biting the head or upper portion of a bird’s neck. They then bite off the head, consume the crop and entrails, and leave behind only the chewed remnants of the body – either at the cage or sometimes many yards away.
Eggs are generally consumed at or near the bird confinement, so broken shells can be evidence of raccoon activity.
Raccoons often injure additional birds in the process of capturing prey, leaving behind tattered nest materials, cracked eggshells, and broken fencing.
Keep poultry in a secure building or enclosure, especially at night.
If necessary electric fences can be placed outside the perimeter of the mesh-wire fences that surround poultry enclosures.
Trapping problematic raccoons.
Raccoons scavenging in the garbage and taking up residence in buildings
The noisiest offense committed by raccoons often involves them clambering into dumpsters for leftover food and climbing onto buildings in search of denning locations. Even if you’re not around to hear them, you can instantly identify the assailant in any case by the telltale smudge marks that raccoons leave on structures when climbing. To prevent raccoons from getting into unwelcome spaces, consider these options:
- Seal or clamp the tops of bins and lock down dumpster lids at night; an unfastened lid is simply an invitation for raccoons to pry them open.
- Place a cap over chimneys.
- Place wide, slick sheet-metal along the edges of the roof and porcupine wiring around downspouts and corners to protect outbuildings
Ensure there aren’t raccoons already present in the chimney or anywhere else inside when starting sealing or exclusion steps. It is better to take preventative measures in early winter – before raccoon mothers find spots to give birth. If you put up barriers during spring/summer, you might trap a raccoon family inside a chimney or other hard-to-reach portion of the building, giving yourself another headache to contend with.
If you do discover a mother rearing young in a building, you can place a rag soaked with coyote urine (the one scent shown to consistently bother raccoons) near the denning spot to convince the raccoons to head elsewhere. (These nocturnal animals will generally depart at night.) If you’re willing to wait a bit longer, you’ll find that after just a few weeks the mother will lead her family out of the building for good, even without any sort of coaxing. Either way, you’ll have a raccoon-free building that is ready to be repaired or have its chimney capped to prevent future intrusion from these masked marauders.
When exclusionary methods have failed and particularly troublesome raccoons are still causing problems, raccoons can be live-captured and relocated by baiting large steel-cage traps.
Live capturing of nuisance raccoons
- Select a large, sturdy steel-cage trap, at least 10 x 12 x 32 inches in size. These are sold at most hardware and farm stores.
- Place trap at the base of a tree or building where raccoons have been visiting.
- Put bait in the back of the trap; choose from pungent items like cat food, sardines, raw chicken, peanut butter, and sugary fruit like apples.
- Release the captured raccoon on property where you have prior permission from the landowner.
Harvest of raccoons with firearms is regulated by many cities and by the Iowa Department of Natural Resources. During some times of the year and in some locations, this may be a viable control option.
Do not use fumigants or toxicants (mothballs, naphthalene, etc.) to repel or remove raccoons from your property. Such chemicals are not approved for exclusion of raccoons and are a health hazard to people, pets, and livestock.
If you’d prefer to have someone else remove a troublesome raccoon, consult with a licensed nuisance wildlife control operator near you.
Summary: solutions to nuisance raccoons - exclude and evict!
- Fencing: on farms, install two-wire electric fences around gardens and chicken coops
- Garbage: firmly clamp the tops of bins and lock down dumpsters at night
- Roofs: cap chimneys and install gable vents or mushroom vents
- Exterior: place sheet-metal on outbuildings & porcupine wire around downspouts and corners
- Scent: deter females and their young from buildings with coyote urine
- Landscaping: trim back tree branches to limit access to roofs and chimneys
- Traps: place live traps near areas raccoons have been visiting or contact wildlife damage-control specialists for assistance
- Season: winter is best: exclude raccoons before they den and give birth in the spring
This article is an update of "Managing Iowa Wildlife: Raccoons" (PM-1302e) originally authored by Jon Judson, William Clark, and James Pease.