color varies from gray to black, and most piglets have
longitudinal stripes until they are about four months old.
the maximum weight for a wild hog is 300 pounds, most male hogs in
the Smokies weigh about 125 pounds with females weighing slightly
less during their average life span of 10 years. At birth, the
piglets weigh roughly two pounds.
are three to five feet in length and stand two to three feet at
the shoulder. Hogs
have poor eyesight, but a keen sense of smell and hearing.
Found mostly in the
western two-thirds of the park, the hogs experience migratory movements in
search of food. Because hogs lack sweat glands, they move into the cooler
climate of the higher elevations during the spring and summer to help
regulate their body temperature, where the under growth of beech and
northern hardwood forests provide an abundance of bulbs, tubers, and
wildflowers. At the end of summer, the hogs migrate down into the oak
forests to feed on acorns and other mast. Male hogs are mostly solitary,
except during the breeding season, while females and piglets gather in
groups of two to three animals.
Wild hogs are
usually nocturnal, but they will have some daytime activity. Like their
domestic relatives, wild hogs will east almost anything. Flowering plants,
mushrooms, snails, snakes, small mammals, bird eggs, salamanders, and
carrion. But the mast crop is the mainstay of the wild hog diet.
The hog behavior of
rooting while searching for food causes the most damage to the park. Many
plant species, including ones that are rare or that take several years to
flower, are eaten, trampled, or uprooted by the tiller action of a
foraging hog. Native animals are also victim to the wild hog through
direct consumption, destruction of habitat, and competition. For example,
red-cheeked salamanders, which are endemic to the park, are commonly found
in hog stomachs.
Both wallowing and
rooting contaminate streams, causing potential problems for the native
brook trout. Hog occupied drainages have been found to have a higher
concentration of bacteria than unoccupied drainages. These bacteria
contaminate water sources, which is a health consideration in heavily used
recreational areas such as the park.
Both sexes have
44 teeth including a well developed set of canines. The upper tusks act as
"whetstones" to keep sharp edges on the lower ones.
The wild hog is an
exotic (non-native) species to the Great Smoky Mountains National Park.
The National Park Service policy is that manipulation of populations of
exotic plant and animal species, up to and including total eradication,
will be undertaken whenever such species threaten the protection or
interpretation of resources being preserved by the park.
The park has found
that a combination of trapping and direct reduction methods has proven to
be the most successful in reducing the numbers of these non-native
mammals. Since the invasion of the wild hog in the late 1940's, nearly
7,500 animals have been removed by trapping and/or shooting. Many of the
hogs removed from the park are trapped and transported to wildlife
management areas to be released for hunting purposes. Of the total number
of animals removed, nearly 6,500 hogs have been removed since 1977.
Funding by the National Resources Preservation Program (NRPP) has been the
most important component in allocating resources for the establishment of
an effective removal program. Since 1986, the first year of NRPP funding,
over 3,800 hogs have been removed from the park. Prior to 1986, an
estimated 2,000 hogs inhabited the park. Current population estimates are
only a few hundred animals.
There is continual
monitoring of wild hogs in the park, including periodic serological
surveys to determine any infectious diseases of hogs in the park.
Vegetation monitoring in fenced off areas called "hog exclosures"
gives researchers a chance to study what happens to forest succession and
species populations after hogs have been excluded from that particular
ecosystem. Past research has included a rooting index which indicates the
distribution of hogs in the park, and a bait enhancement study to
determine if the hogs had a bait preference in an effort to facilitate
trapping methods. Despite 30 years of management, more than 500 hogs
remain in the Park. Future efforts may maintain populations at minimal
levels, but elimination is unlikely.