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Wildlife, Animals, and Plants
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BIOLOGICAL DATA AND HABITAT REQUIREMENTS
WILDLIFE SPECIES: Procyon lotor | Raccoon
TIMING OF MAJOR LIFE HISTORY EVENTS :
Breeding season - Raccoons are polygamous. Throughout most of their
range raccoons mate from January to March, with a peak in February. In
the extreme southeastern United States mating typically occurs later
than it does farther north and continues later into the summer. In
South Carolina, Georgia, and Louisiana most raccoons mate in March. In
Alabama mating occurs from March to June or later, with the peak in
April. Adult females that fail to become pregnant during their first
estrus in the spring may breed again 2 to 4 months later [6]. Raccoons
may breed in their first year or not until their second year [26].
Yearling females that fail to conceive during their first cycle probably
do not breed until the next year [6].
Gestation and litter size - Gestation usually lasts from 63 to 65 days,
with reported extremes of 54 and 70 days. Litters of one to eight have
been reported, with mean litter sizes ranging from two to five.
Generally only one litter is produced per year [6,26,30].
Development of young - Raccoons begin walking 4 to 6 weeks after birth,
and can generally walk, run, and climb when they are 7 weeks old.
Weaning begins when the young leave the den and begin to forage for
themselves. Most are weaned by the time they are 16 weeks old, but some
may continue to nurse occasionally for several months more. Dispersal
of young from their natal den generally occurs in the year following
their birth; however, some litters may disperse the fall of their first
year [6].
Social organization - Except for females and young, which tend to move
as a family group, raccoons are usually solitary. Several raccoons
often den together during extremely cold weather; however, and
individuals may feed together at a concentrated food source. Raccoons
pair only during the breeding season [30].
Activity - Raccoons are typically nocturnal. The peak of feeding
activity generally occurs before midnight. Activity rarely begins more
than 1 hour before sunset, but return to the daytime resting site is
occasionally delayed for several hours after sunrise. Where
sub-freezing temperatures and permanent snow cover prevail during the
winter in northern latitudes, raccoons typically sleep for several
months during the winter. Snow cover is more important than low
temperatures in initiating dormancy. Later in the winter, however, 1 to
3 days of temperatures above freezing may bring raccoons out to forage
even in deep snow. In the southern states raccoons are generally active
throughout the winter [6].
Life span - Most raccoons in the wild live less than 5 years. Mean life
spans of 3.1 and 1.8 years have been reported [6]. Raccoons in
captivity have lived as long as 13 years [2].
PREFERRED HABITAT :
Raccoons are most abundant near water, especially in bottomland forests
along streams, hardwood swamps, flooded areas around reservoirs,
marshes, and mangrove swamps. Populations are low in southern pine
forests, deserts, and mountains above 6,560 feet (2,000 m). Raccoons
tend to avoid large open fields; where they have moved onto the prairies
of the northern United States and southern Canada they favor buildings,
woodlots, and wetlands [6]. A mosaic of small open areas and forested
areas with numerous den trees along streams usually sustains the highest
population densities of raccoons [30].
Home range - There is great variation in the home range sizes reported
for raccoons. Most of the home range diameters fall between 0.6 and 1.9
miles (1-3 km); the maximum reported was 4 miles (6.4 km) [4,6,35].
Adult males generally have larger home ranges than adult females, and
may temporarily expand their ranges to visit several females during the
mating period. Females greatly restrict their movements during the
first few weeks after their litters are born, and juveniles occupy their
mother's home range for at least the first few months after leaving the
den. Home ranges of males and females as well as ranges of raccoons of
the same sex tend to overlap broadly [6].
COVER REQUIREMENTS :
Winter dens - The most commonly used winter dens are in hollow trees.
Tree dens may be in any hollow limb or trunk of sufficient size. Den
cavities examined by Stuewer [35] averaged 11 by 14 inches (29 by 36
cm), and were mostly from 10 to 39 feet (3-12 m) above the ground.
Well-insulated winter den sites may be especially important to raccoon
survival in the northern part of their range [11].
Ground burrows dug by common gray fox (Urocyon cinereoargenteus), red
fox (Vulpes vulpes), woodchuck (Marmota monax), striped skunk (Mephitis
mephitis), and American badger (Taxidea taxus) are also used, especially
in areas where hollow trees are scarce. Other winter den sites are in
rock crevices and caves, abandoned buildings, brush piles, and on the
ground in swamps under clumps of cedar (Thuja spp.). Common muskrat
(Ondatra zibethicus) houses are used occasionally in marshes where
hollow trees are scarce [6,26,30].
Natal dens - A pregnant female chooses a new den in which to have her
litter. In many areas, hollow trees are the most popular choice.
Underground burrows are also used. Litters may also be raised in rock
crevices, caves and abandoned mine shafts, brush and slash piles,
sawdust piles, common muskrat lodges, wood duck (Aix sponsa) boxes, and
magpie (Pica spp.) nests [6].
All dens are generally located 220 to 460 feet (67-140 m) from water [6].
Daytime rest sites - In marshes, swamps, and open fields the most common
resting site is on the ground in herbaceous vegetation. Usually no nest
is prepared, but in saltmarshes raccoons build flat platforms of
cordgrass (Spartina spp.) and rush (Juncus spp.) as much as 1 mile (1.6
km) from dry land. Raccoons also rest during the day on bare tree
limbs, mashed-down eastern gray squirrel (Sciurus carolinensis) nests,
and in clumps of Spanish moss (Tillandsia usneoides) [6,21]. Raccoons
may change daytime rest sites daily [6].
FOOD HABITS :
Raccoons are omnivorous. They eat carrion, garbage, birds, mammals,
insects, crayfish (Cambarus spp., Astacus spp.), mussels, other
invertebrates, a wide variety of grains and other fruits, and other
plant materials. They are selective when food is abundant but eat
whatever is available when food is scarce [6,26,30].
Wild cherries (Prunus spp.), apples (Malus spp.), persimmons (Diospyros
spp.), and grapes (Vitis spp.) and other berries of all kinds are eaten
whenever they are available. Cultivated fruits such as peaches (P.
persica), plums (P. augustifolia), figs (Ficus carica), citrus fruits
(Citrus spp.), and watermelons (Citrullus vulgaris) are taken on
occasion. Nuts, especially acorns, are important seasonal foods.
American beech (Fagus grandifolia), hickory (Carya spp.), and pecan
(Carya illinoensis) nuts, and walnut (Juglans spp.) fruits are also
eaten. Corn is the most important item in the diet in some areas
[6,26,30].
The most important animal food is crayfish. Insects, especially
grasshoppers, beetles, caterpillars, and true bugs, are also commonly
eaten. Among mammals, rodents are the most commonly eaten, including
gophers (Geomyidae), ground squirrels (Spermophilus spp.), and tree
squirrels (Sciuridae). Young common muskrat are sometimes eaten in the
spring, while adults may be taken from traps or as carrion. Cottontails
(Sylvilagus spp.) and other rabbits (Leporidae), shrews (Soricidae), and
moles (Talpidae) are also commonly eaten. Even jackrabbits (Lepus
spp.), small raccoons, and mink (Mustela vison) are occasionally eaten.
Garbage is a common element of the diet of raccoons around farms and
towns [6].
Raccoons sometimes eat passerine birds (Passeriformes), woodpeckers
(Picidae), ring-necked pheasants (Phasianus colchicus), and northern
bobwhite (Colinus virginianus). Occasionally they also take ducks
(Antidae) and American coots (Fulica americana). Waterfowl are most
often taken as cripples or carrion during the hunting season. Raccoons
also eat bird eggs, including those of ring-necked pheasant, northern
bobwhite, wild turkey (Meleagris gallopavo), ducks, and shorebirds
(Charadriiformes) [6,15].
Turtles and especially their eggs are eaten in some areas. Fishes are
often taken in small numbers, and may temporarily become important food
items when they are easily caught in drying pools [6].
Despite the great variety of foods eaten, raccoons tend to follow a
general pattern of seasonal diet changes. Only in the spring do most
raccoons eat more animal than plant food. Crayfish are the most
important food at this time, followed by insects and small vertebrates.
Acorns are also an important food early in the spring before other foods
are available [6].
During the summer raccoons in most habitats primarily eat fruits. The
most important animal foods are crayfish, followed by insects and small
vertebrates [6,33]. In the fall plants, especially fruits, continue to
be more important than animals in the raccoon diet. Acorns become the
most important food in the winter [6].
PREDATORS :
Raccoon predators include mountain lions (Felis concolor), bobcats (Lynx
rufus), gray wolves (Canis lupus), red foxes, coyotes (C. latrans),
fishers (Martes pennanti), and owls (Strigiformes) [26]. Humans hunt
and trap raccoons [6].
MANAGEMENT CONSIDERATIONS :
Habitat management - To enhance and maintain habitat quality for
raccoons, managers should protect small woodlands in agricultural areas
from severe fire, harvest, and grazing. Wild fruits should be
encouraged, and mast producing trees (especially oaks and American
beech) should be preserved. Streams, swamps, marshes, and beaver
(Castor canadensis) colonies should be protected from destruction and
pollution, and ponds and marshes should be constructed near woodlands.
Den trees and potential den trees should be given special protection.
Stuewer [35] recommended leaving at least one, preferably two den trees
per 15 to 20 acres (6-8 ha) and within 0.25 mile (0.4 km) of a permanent
water supply. Where natural dens are scarce, artificial den boxes
should be set up in woodlands near water [6]. Information regarding
artificial dens for raccoons is available in Stuewer [36].
Wilson [41] discussed the following recommendations for improving
woodland areas for raccoons in North Carolina: (1) cut no hollow trees
during logging; (2) install artificial dens if den trees are lacking;
(3) manage woodlands for oaks, persimmons, and grapes (including
planting fencerows and field borders with persimmons and grapes); and
(4) keep livestock out of the woods.
Raccoons have been used as indicator species for monitoring of
environmental zoonosis (a disease communicable from lower animals to
humans under natural conditions) and pollutants. In Florida raccoon
serum is routinely examined for evidence of St. Louis encephalitis,
Venezuelan equine encephalitis, and eastern equine encephalomyelitis
[6].
The literature on raccoon parasites and diseases is voluminous. The
only diseases likely to have a significant impact on raccoon populations
are canine distemper and rabies [22]. Distemper is widespread in
raccoon populations. Although rabies is common in raccoon populations,
it does not appear to spread readily from raccoons to other species.
Rabid raccoons are often passive and unaggressive. Raccoons carry at
least 13 pathogens known to cause disease in humans [6]. Extensive
bibliographies on parasites and diseases of raccoons are available in
Halloran [17] and Sanderson and others [31].
Raccoons are one of the most frequent nuisance animals reported by
wildlife agencies in urban and suburban areas of the United States [8].
Raccoons sometimes cause agricultural damage in orchards, vineyards,
melon patches, corn fields, peanut fields, and chicken yards. They are
sometimes regarded as serious threats to nesting waterfowl. In many
cases, however, raccoon damage to crops and game species is
inconsequential, temporary, or very local and often caused by only one
or a few individuals [6].
Human activities - Hunting, trapping, and automobile road kills are
believed to be the main cause of mortality in many parts of the
raccoon's range [30].
REFERENCES :
NO-ENTRY
Related categories for Wildlife Species: Procyon lotor
| Raccoon
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