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cattails.
Raccoons do not hibernate, but remain inactive for extended periods during severe winter weather. They will use communal or group dens during winter storms. A raccoon uses several dens within its home range. On summer days, it spends much of its time on the ground or sprawled on a large tree limb.
Depending on seasonal needs, most foraging is done in or near water or around the edges of cropfields. A raccoon hunts in shallow water by turning over rocks and limbs, and probing and grabbing with its front feet. It examines potential food items by manipulating them with its front feet and touching them with its nose.
Foods
Raccoons are omnivorous (they eat both animals and plants) and opportunistic; their diet is dictated by seasonal protein and energy needs and food availability. In spring, females feed primarily on high protein animal matter to insure development and growth of their young. Crayfish, insects, birds, eggs, fish and young rabbits are eaten when available. Later in the summer, after the young are weaned, the female's protein requirements are greatly reduced, allowing her to take advantage of a wide variety of fruits and vegetables including mulberries, sweet corn and plums.
With the cooler temperatures of fall, raccoons feed intensively to build fat reserves for winter. Energy-rich foods including nuts and grain (such as corn) and high protein foods are pursued at this time. In winter, raccoons feed on waste grain, carrion and assorted small animals and insects, but rely on fat reserves to sustain them during long periods of inactivity.
Reproduction
Breeding occurs between January and March, and peaks in February. Raccoons pair only to mate, and do not form long-term pair-bonds. Males will mate with more than one female and do not share in the rearing of young. Pregnancy lasts about nine weeks, and the young are weaned at seven to 10 weeks. The young begin to accompany their mother on excursions by early June.
In Nebraska, yearling female raccoons breed at a lower rate and have smaller litters than do older, adult females. Less than 70 percent of yearling females are bred, with average litter size of 3.3 young. Ninety-five percent of adult females are bred, and have an average of 4 young per litter. Breeding by adult females is relatively constant from year to year, while breeding by yearlings can be quite variable. Yearling breeding rates are thought to reflect the severity of the previous winter and the overall health of the population.
Mortality
Studies in Iowa show that survival of young raccoons from birth until September is about 65 percent, while survival from September through the following spring is 30 to 50 percent. Annual survival of adult raccoons is around 60 percent. Raccoons in the Midwest can sustain an annual harvest of up to 35 to 40 percent of the fall population.
The major causes of mortality for raccoons in the Midwest are fur harvest, collisions with motor vehicles and disease. Starvation is seldom an important population regulator in the Midwest. As fur harvest decreases, mortality from other causes will likely increase. The most important disease in raccoons in Nebraska is canine distemper, which can cause severe reductions in raccoon numbers in localized areas. Most sick raccoons reported in Nebraska are diagnosed as having distemper. Although the symptoms of distemper are similar to those of rabies, raccoons in Nebraska seldom are diagnosed as having rabies.
Importance
Raccoons seldom cause serious problems for homeowners, farmers or ranchers but their curious nature can be irritating. Trash cans and dog food containers must sometimes be modified to exclude raccoons. The raccoon's wellknown love of corn usually causes only slight damage to field corn yields but sweet corn stands are sometimes decimated. Damage is usually controlled by removing the offending animals. Relecation of damage-causing raccoons is often preferable to killing them, particularly in urban situations. However, relocated raccoons don't compete well with established residents and have poor survival rates.
Raccoons sometimes prey upon the nests of ground-nesting birds such as ducks and pheasants, and on the nests of cavitynesting birds such as bluebirds. However, predation is among the checks and
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