Raccoon Information and Control

Lake Tahoe, CA & Stateline & Carson City, NV

The raccoon, Procyon lotor (sometimes misspelled racoon[2]), also known as the common raccoon,[3] North American raccoon,[4] northern raccoon[5] and colloquially as coon,[6] is a medium-sized mammal native to North America. It is the largest of the procyonid family, having a body length of 40 to 70 cm (16 to 28 in) and a body weight of 3.5 to 9 kg (8 to 20 lb). The raccoon is usually nocturnal and is omnivorous, with a diet consisting of about 40% invertebrates, 33% plant foods, and 27% vertebrates. It has a grayish coat, of which almost 90% is dense underfur, which insulates against cold weather. Two of its most distinctive features are its extremely dexterous front paws and its facial mask, which are themes in the mythology of several Native American tribes. Raccoons are noted for their intelligence, with studies showing that they are able to remember the solution to tasks up to three years later.

The original habitats of the raccoon are deciduous and mixed forests of North America, but due to their adaptability they have extended their range to mountainous areas, coastal marshes, and urban areas, where many homeowners consider them to be pests. As a result of escapes and deliberate introductions in the mid-20th century, raccoons are now also distributed across the European mainland, the Caucasus region and Japan.

Though previously thought to be solitary, there is now evidence that raccoons engage in gender-specific social behavior. Related females often share a common area, while unrelated males live together in groups of up to four animals to maintain their positions against foreign males during the mating season, and other potential invaders. Home range sizes vary anywhere from 3 hectares for females in cities to 50 km2 for males in prairies (7 acres to 20 sq mi). After a gestation period of about 65 days, two to five young, known as "kits", are born in spring. The kits are subsequently raised by their mother until dispersion in late fall. Although captive raccoons have been known to live over 20 years, their average life expectancy in the wild is only 1.8 to 3.1 years. In many areas, hunting and vehicular injury are the two most common causes of death.

Head to hindquarters, raccoons measure between 40 and 70 cm (16 and 28 in), not including the bushy tail which can measure between 20 and 40 cm (8 and 16 in), but is usually not much longer than 25 cm (10 in).[29] The shoulder height is between 23 and 30 cm (9 and 12 in).[30] The skull of the adult male measures 94.3–125.8 mm long and 60.2–89.1 mm wide, while that of the female measures 89.4–115.9 mm long and 58.3–81.2 mm wide.[31] The body weight of an adult raccoon varies considerably with habitat; it can range from 2 to 14 kilograms (4 to 30 lb), but is usually between 3.5 and 9 kilograms (8 and 20 lb). The smallest specimens are found in Southern Florida, while those near the northern limits of the raccoon's range tend to be the largest (see Bergmann's rule).[32] Males are usually 15 to 20% heavier than females.[33] At the beginning of winter, a raccoon can weigh twice as much as in spring because of fat storage.[34] It is one of the most variably sized of all mammals. The largest recorded wild raccoon weighed 28.4 kg (62.6 lb) and measured 140 cm (55 in) in total length, by far the largest size recorded for a procyonid.[35][36]

The most characteristic physical feature of the raccoon is the area of black fur around the eyes, which contrasts sharply with the surrounding white face coloring. This is reminiscent of a "bandit's mask" and has thus enhanced the animal's reputation for mischief.[37] The slightly rounded ears are also bordered by white fur. Raccoons are assumed to recognize the facial expression and posture of other members of their species more quickly because of the conspicuous facial coloration and the alternating light and dark rings on the tail. The rings resemble those of a ringtail lemur.[38][39] The dark mask may also reduce glare and thus enhance night vision.[39] On other parts of the body, the long and stiff guard hairs, which shed moisture, are usually colored in shades of gray and, to a lesser extent, brown.[40] Raccoons with a very dark coat are more common in the German population because individuals with such coloring were among those initially released to the wild.[41] The dense underfur, which accounts for almost 90% of the coat, insulates against cold weather and is composed of 2 to 3 cm (0.8 to 1.2 in) long hairs.[40] Raccoon baculum or "penis bone"

The raccoon, whose method of locomotion is usually considered to be plantigrade, can stand on its hind legs to examine objects with its front paws.[42] As raccoons have short legs compared to their compact torso, they are usually not able either to run quickly or jump great distances.[43] Their top speed over short distances is 16 to 24 km/h (10 to 15 mph).[44][45] Raccoons can swim with an average speed of about 5 km/h (3 mph) and can stay in the water for several hours.[46] For climbing down a tree headfirst—an unusual ability for a mammal of its size—a raccoon rotates its hind feet so they are pointing backwards.[47] Raccoons have a dual cooling system to regulate their temperature; that is, they are able to both sweat and pant for heat dissipation.[48]

The most important sense for the raccoon is its sense of touch.[53] The "hyper sensitive"[54] front paws are protected by a thin horny layer which becomes pliable when wet.[55] The five digits of the paws have no webbing between them, which is unusual for a carnivoran.[56] Almost two-thirds of the area responsible for sensory perception in the raccoon's cerebral cortex is specialized for the interpretation of tactile impulses, more than in any other studied animal.[57] They are able to identify objects before touching them with vibrissae located above their sharp, nonretractable claws.[58] The raccoon's paws lack an opposable thumb and thus it does not have the agility of the hands of primates.[59] There is no observed negative effect on tactile perception when a raccoon stands in water below 10 °C (50 °F) for hours.[60]

Raccoons are thought to be color blind or at least poorly able to distinguish color, though their eyes are well-adapted for sensing green light.[61] Although their accommodation of 11 dioptre is comparable to that of humans and they see well in twilight because of the tapetum lucidum behind the retina, visual perception is of subordinate importance to raccoons because of their poor long-distance vision.[62] In addition to being useful for orientation in the dark, their sense of smell is important for intraspecific communication. Glandular secretions (usually from their anal glands), urine and feces are used for marking.[63] With their broad auditory range, they can perceive tones up to 50–85 kHz as well as quiet noises like those produced by earthworms underground.[64] Intelligence

The shape and size of a raccoon's home range varies depending on age, gender, and habitat, with adults claiming areas more than twice as large as juveniles.[76] While the size of home ranges in the inhospitable habitat of North Dakota's prairies lay between 7 and 50 km2 (3 and 20 sq mi) for males and between 2 and 16 km2 (1 and 6 sq mi) for females, the average size in a marsh at Lake Erie was 0.49 km2 (0.19 sq mi).[77] Irrespective of whether the home ranges of adjacent groups overlap, they are most likely not actively defended outside the mating season if food supplies are sufficient.[78] Odor marks on prominent spots are assumed to establish home ranges and identify individuals.[79] Urine and feces left at shared latrines may provide additional information about feeding grounds, since raccoons were observed to meet there later for collective eating, sleeping and playing.[80]

Though usually nocturnal, the raccoon is sometimes active in daylight to take advantage of available food sources.[82] Its diet consists of about 40% invertebrates, 33% plant material and 27% vertebrates.[83] Since its diet consists of such a variety of different foods, Zeveloff argues the raccoon "may well be one of the world's most omnivorous animals".[84] While its diet in spring and early summer consists mostly of insects, worms, and other animals already available early in the year, it prefers fruits and nuts, such as acorns and walnuts, which emerge in late summer and autumn, and represent a rich calorie source for building up fat needed for winter.[85] They eat active or large prey, such as birds and mammals, only occasionally, since they prefer prey that is easier to catch, specifically fish and amphibians.[86] Bird nests (eggs and hatchlings) are frequently preyed on, and small birds are often helpless to defend against the attacking raccoon.[87] When food is plentiful, raccoons can develop strong individual preferences for specific foods.[88] In the northern parts of their range, raccoons go into a winter rest, reducing their activity drastically as long as a permanent snow cover makes searching for food impossible.[89]

Raccoons sample food and other objects with their front paws to examine them and to remove unwanted parts. The tactile sensitivity of their paws is increased if this action is performed underwater, since the water softens the hard layer covering the paws.[90] However, the behavior observed in captive raccoons in which they carry their food to a watering hole to "wash" or douse it before eating has not been observed in the wild.[91] Naturalist Georges-Louis Leclerc, Comte de Buffon (1707–1788) believed that raccoons do not have adequate saliva production to moisten food, necessitating dousing, but this is certainly incorrect.[92] Captive raccoons douse their food more frequently when a watering hole with a layout similar to a stream is not farther away than 3 m (10 ft).[93] The widely accepted theory is that dousing is a vacuum activity imitating foraging at shores for aquatic foods.[94] This is supported by the observation that such foods are doused more frequently. Cleaning dirty food does not seem to be a reason for "washing".[93] Experts have cast doubt on the veracity of observations of wild raccoons dousing food.[95]

Raccoons usually mate in a period triggered by increasing daylight between late January and mid-March.[96] However, there are large regional differences which are not completely explicable by solar conditions. For example, while raccoons in southern states typically mate later than average, the mating season in Manitoba also peaks later than usual in March and extends until June.[97] During the mating season, males roam their home ranges in search of females in an attempt to court them during the three to four day period when conception is possible. These encounters will often occur at central meeting places.[98] Copulation, including foreplay, can last over an hour and is repeated over several nights.[99] The weaker members of a male social group also are assumed to get the opportunity to mate, since the stronger ones cannot mate with all available females.[100] In a study in southern Texas during the mating seasons from 1990 to 1992, about one third of all females mated with more than one male.[101] If a female does not become pregnant or if she loses her kits early, she will sometimes become fertile again 80 to 140 days later.[102]

After usually 63 to 65 days of gestation (although anywhere from 54 to 70 days is possible), a litter of typically two to five young is born.[103] The average litter size varies widely with habitat, ranging from 2.5 in Alabama to 4.8 in North Dakota.[104] Larger litters are more common in areas with a high mortality rate, due, for example, to hunting or severe winters.[105] While male yearlings usually reach their sexual maturity only after the main mating season, female yearlings can compensate for high mortality rates and may be responsible for about 50% of all young born in a year.[106] Males have no part in raising young.[107] The kits (also called "cubs") are blind and deaf at birth, but their mask is already visible against their light fur.[108] The birth weight of the about 10 cm (4 in)-long kits is between 60 and 75 g (2.1 and 2.6 oz).[109] Their ear canals open after around 18 to 23 days, a few days before their eyes open for the first time.[110] Once the kits weigh about 1 kg (2 lb), they begin to explore outside the den, consuming solid food for the first time after six to nine weeks.[111] After this point, their mother suckles them with decreasing frequency; they are usually weaned by 16 weeks.[112] In the fall, after their mother has shown them dens and feeding grounds, the juvenile group splits up.[113] While many females will stay close to the home range of their mother, males can sometimes move more than 20 km (12 mi) away.[114] This is considered an instinctive behavior, preventing inbreeding.[115] However, mother and offspring may share a den during the first winter in cold areas.[116]

Captive raccoons have been known to live for more than 20 years.[117] However, the species' life expectancy in the wild is only 1.8 to 3.1 years, depending on the local conditions in terms of traffic volume, hunting, and weather severity.[118] It is not unusual for only half of the young born in one year to survive a full year.[119] After this point, the annual mortality rate drops to between 10% and 30%.[120] Young raccoons are vulnerable to losing their mother and to starvation, particularly in long and cold winters.[121] The most frequent natural cause of death in the North American raccoon population is distemper, which can reach epidemic proportions and kill most of a local raccoon population.[122] In areas with heavy vehicular traffic and extensive hunting, these factors can account for up to 90% of all deaths of adult raccoons.[123]

The most important natural predators of the raccoon are bobcats, coyotes, and great horned owls, the latter mainly preying on young raccoons. In the Chesapeake Bay, raccoons are the most important mammalian prey for bald eagles.[124] In their introduced range in the former Soviet Union, their main predators are wolves, lynxes and eagle owls.[125] However, predation is not a significant cause of death, especially because larger predators have been exterminated in many areas inhabited by raccoons.[126]

Although they have thrived in sparsely wooded areas in the last decades, raccoons depend on vertical structures to climb when they feel threatened.[127] Therefore, they avoid open terrain and areas with high concentrations of beech trees, as beech bark is too smooth to climb.[128] Tree hollows in old oaks or other trees and rock crevices are preferred by raccoons as sleeping, winter and litter dens. If such dens are unavailable or accessing them is inconvenient, raccoons use burrows dug by other mammals, dense undergrowth, roadside culverts in urban areas, or tree crotches.[129] In a study in the Solling range of hills in Germany, more than 60% of all sleeping places were used only once, but those used at least ten times accounted for about 70% of all uses.[130] Since amphibians, crustaceans, and other animals found around the shore of lakes and rivers are an important part of the raccoon's diet, lowland deciduous or mixed forests abundant with water and marshes sustain the highest population densities.[131] While population densities range from 0.5 to 3.2 animals per square kilometre (0.2 – 1.2 animals per square mile) in prairies and do not usually exceed 6 animals per square kilometer (2.3 animals per square mile) in upland hardwood forests, more than 20 raccoons per square kilometer (50 animals per square mile) can live in lowland forests and marshes.[132]

Due to its adaptability, the raccoon has been able to use urban areas as a habitat. The first sightings were recorded in a suburb of Cincinnati in the 1920s. Since the 1950s, raccoons have been present in Philadelphia, Washington, DC, New York City, Chicago, San Francisco, Los Angeles, and Toronto.[157] Since the 1960s, Kassel has hosted Europe's first and densest population in a large urban area, with about 50 to 150 animals per square kilometre (130–400 animals per square mile), a figure comparable to those of urban habitats in North America.[157][158] Home range sizes of urban raccoons are only three to 40 hectares (7.5–100 acres) for females and eight to 80 hectares (20–200 acres) for males.[159] In small towns and suburbs, many raccoons sleep in a nearby forest after foraging in the settlement area.[157][160] Fruit and insects in gardens and leftovers in municipal waste are easily available food sources.[161] Furthermore, a large number of additional sleeping areas exist in these areas, such as hollows in old garden trees, cottages, garages, abandoned houses, and attics. The percentage of urban raccoons sleeping in abandoned or occupied houses varies from 15% in Washington, DC (1991) to 43% in Kassel (2003).[162]

The increasing number of raccoons in urban areas has resulted in diverse reactions in humans, ranging from outrage at their presence to deliberate feeding.[176] Some wildlife experts and most public authorities caution against feeding wild animals because they might become increasingly obtrusive and dependent on humans as a food source.[177] Other experts challenge such arguments and give advice on feeding raccoons and other wildlife in their books.[178][179] Raccoons without a fear of humans are a concern to those who attribute this trait to rabies, but scientists point out this behavior is much more likely to be a behavioral adjustment to living in habitats with regular contact to humans for many generations.[180] Serious attacks on humans by groups of non-rabid raccoons are extremely rare and are almost always the result of the raccoon feeling threatened; at least one such attack has been documented.[181] Raccoons usually do not prey on domestic cats and dogs, but individual cases of killings have been reported.[182]

While overturned waste containers and raided fruit trees are just a nuisance to homeowners, it can cost several thousand dollars to repair damage caused by the use of attic space as dens.[183] Relocating or killing raccoons without a permit is forbidden in many urban areas on grounds of animal welfare. These methods usually only solve problems with particularly wild or aggressive individuals, since adequate dens are either known to several raccoons or will quickly be rediscovered.[171][184] Loud noises, flashing lights and unpleasant odors have proven particularly effective in driving away a mother and her kits before they would normally leave the nesting place (when the kits are about eight weeks old).[171][185] Typically, though, only precautionary measures to restrict access to food waste and den sites are effective in the long term.[171][186]

Among all fruits and crops cultivated in agricultural areas, sweet corn in its milk stage is particularly popular among raccoons.[187] In a two-year study by Purdue University researchers, published in 2004, raccoons were responsible for 87% of the damage to corn plants.[188] Like other predators, raccoons searching for food can break into poultry houses to feed on chickens, ducks, their eggs, or feed.[171][189] Since they may enter tents and try to open locked containers on camping grounds, campers are advised to not keep food or toothpaste inside a tent.[190]

Since raccoons in high mortality areas have a higher rate of reproduction, extensive hunting may not solve problems with raccoon populations. Older males also claim larger home ranges than younger ones, resulting in a lower population density. The costs of large-scale measures to eradicate raccoons from a given area are usually many times higher than the costs of the damage done by the raccoons. - Wikipedia