POSSUMS

Opossums are a member of the order Marsupialia, a primitive group of mammals found most commonly in Australia. Kangaroos, koalas and wombats are other wellknown marsupials.

The Virginia opossum is among the most primitive and generalized of marsupials. Its closest relative is the Centra]

American opossum. An adult opossum is 2 to 3 feet long and weighs between 4 and 12 pounds. It has an elongated snout, a pink nose, black eyes and prominent, naked black ears. Its head is usually white and its coarse body fur is mostly grayish white but tends to be darker on its legs.

An opossum is well-adapted for climbing. Its feet are plantigrade (shaped so the opossum walks of the sole of its foot with the heel touching the ground) and its toes are dexterous (skillful, like fingers). Its hind feet have a toe that resembles a thumb and makes them look somewhat like human hands. Its naked, scaly tail is able to wrap around and grasp limbs and can support the animal's full weight for short penods.

The opossum's skull has 50 teeth, the highest number found in any mammal.

DISTRIBUTION AND ABUNDANCE

Prior to the European settlement of North America, the Virginia opossum was found only in Central America and the southeastern United States. During the 1900s, its range expanded northward and westward. Its northem distribution is limited by winter temperatures and its westem distribution is limited by dry, hot climates. The opossum has been introduced along the Pacific Coast and is currently found from southern Califomia to southwestern British Columbia.

Extreme southeastem Nebraska was part of the opossum's presettlement range and it is now common in southem and eastern Nebraska. In the Sandhills and Panhandle, opossums are restricted to major drainages such as the Loup, Niobrara and North Platte rivers.

HABITAT AND HOME

Opossums and raccoons share similar habitat requirements and both species use similar areas in a similar manner. Good opossum habitat includes a combination of large trees and shrub thickets, abundant water and crop fields. An opossum will den nearly anywhere that is dry, sheltered and safe, such as the abandoned dens of other animals, hollow trees and logs and brushpiles. A nest of leaves and grass is usually made at the den site. An opossum will use a number of dens within its home range.

HABITS

An opossum is primarily nocturnal (active at night) but may become diurnal (active during daylight hours) during cold weather. An adult male's home range is about 250 acres and tends to shift through the course of its life, while the adult female's home range is smaller, about 125 acres, and is more permanent. An adult male is solitary, while an adult female is with her young through most of the year. The young of the first litter begin living on their own away from the nest when they are three months old, but second-litter young stay with the mother until the following spring. Litter-mates may share common dens for up to three months after separation from their mother.

An opossum does not hibernate, but remains inactive for short periods during severe winter weather. However, its energy reserves are not as extensive as those of a raccoon, so it must forage on a regular basis, even during extreme weather conditions.

An opossum is a very slow runner and will try to escape predators by climbing the nearest tree. When cornered on the ground, it initially exhibits a threatening posture, hissing and making low growls. If attacked, it generally lies very still as if paralyzed or dead, a habit called playing possum. It also emits a foul smelling substance when threatened.

FOODS

An opossum does not have a method for storing food or energy and needs food sources that are stable from season to season and year to year. Its diet includes a wide variety of foods, including insects, earthworms, small mammals, fruits, grains, plants, and the flesh of dead animals it happens to find. It forages intensively in a small area on whatever is available. When food resources become depleted in one place, the animal simply moves to a new area. Although the foods an opossum eats are varied, they must be abundant and closely spaced. Extreme weather conditions, such as a severe drought or extended cold, can reduce food availability and have devastating effects on opossum populations.

REPRODUCTION

A female opossum usually has two litters per year. Mating occurs in mid-January through February and continues into August. Young partially-developed opossums are born 13 days after mating. They migrate to the female's pouch where they continue to develop for several weeks. The young emerge from the pouch when they are 1 l/2 to 2 months old and ride on their mother's back. They are weaned at three months. The adult female mates again soon after the first litter is weaned, and the first litter disperses within one month of weaning. Young from the second litter are weaned and on their own by September or October. There are 8 to 10 young in an average litter, but litters of 17 have been reported. The young are capable of reproducing at six months of age, but usually don't until the year after they are born.

MORTALITY

An opossum is short-lived and has high mortality rates at all stages. Mortality of young still in the pouch ranges from 10 to 25 percent. Of those that survive through weaning, fewer than 10 percent live longer than one year. The oldest known wild opossums were 2 l/2 to 3 years old.

The most important mortality factors are caused by humans, predation, parasites and disease, exposure and starvation. Human-caused mortalities include hunting, trapping and highway collisions. Important predators include great horned owls, dogs and coyotes. An opossum is a host to a multitude of internal and external parasites including intestinal worms, fleas and ticks. These generally are debilitating and increase susceptibility to diseases and malnutrition. An opossum is highly resistant to rabies.

IMPORTANCE

Opossums seldom cause problems for homeowners, ranchers or farmers. They sometimes raid trash cans or dog food containers, but these situations are easily remedied by denying access to the containers.

The opossum is classified as a furbearer in Nebraska but is not taken in large numbers by hunters or trappers, and its pelt has little value. Opossum furs are primarily used to trim inexpensive cloth garments.

From 1941 to 1989, over 350,000 opossums were taken by fur hunters and trappers. Harvest totals from 1980 to 1989 indicate an average annual harvest of 11,900 opossums valued at $7,200. From 1984 to 1989, only 42 percent of the harvested opossum pelts were sold.

The uniqueness of the opossum intrigues scientists and nature enthusiasts. It is the only marsupial in the United States. In Australia and elsewhere, marsupials have been out-competed and even driven to extinction by more modern mammals. Yet, the opossum has adapted to the changing environment in the U.S. with its simple manner, and continues to thrive.

General Opossum Information

Like the kangaroo, this unique mammal has an abdominal pouch for carrying her young.

Description/Biology:

Opossums have a repulsive, musk like odor and can be an occasional nuisance when they enter crawl spaces, under decks, garages and similar areas.

The opossum is 2-3 feet long. Its head is white to yellowish with a pink nose, black eyes and bluish black, naked ears.

Adults are long-haired, light-gray, and about the size of a large cat weighing 4-15 lbs.

It has a long scaly tail, black at its base, grading to yellow-white or pink for the rest of its length.

The average number of young is 6, but as many as 13 may be born.

They nurse in the mother's pouch for about 3 months.

Opossums are very resistant to rabies and have far fewer cases of rabies than any other common wild animal in United States.

Opossums have been found to be a primary carrier of a deadly disease in horses known as  : Protozoal Myeloencephalitis . Click on that link for more information about this.

Steps should be taken to keep opossums away from horses, horse feed, and stables.

Habitat:

They prefer to live in wooded areas, near streams.

They choose home sites such as hollow logs, abandoned woodchuck burrows, under buildings and decks, in garages, trash heaps, or cavities in hollow trees.

Habits:

This shy and secretive animal is seldom seen because it is abroad mostly at night.

Perhaps it is most often observed along highways in the glare of automobile headlights as it feeds on animals killed by traffic.

While opossums tend to wander a great deal and shift their home sites frequently, individuals spend most of their lives within about 40 acres .

Opossums often climb trees or brush heaps in an attempt to escape, when pursued.

When frightened, the animal rolls over on it's side, shuts its eyes becoming limp.

The opossum is "playing possum" with it's heartbeat slowing down to the appearance of death.

This is a reaction is a nervous shock, the opossum is able to recover.

Opossums eat fish, birds, mammals, crustaceans, insects, mushrooms, fruits, grass, eggs and dead animals.

CONTROL

Denying their access to structures by exclusion techniques is the most effective method of controlling opossums.

Live animal traps such as   Havahart Raccoon Traps, or the easy to set Havahart 1085 Easy Set Cage Style Animal Live Trap can be used to capture and relocate

The traps should be set in locations the animal frequents or where it is causing damage.
Fish, canned cat or dog food are good opossum baits.
To readily entice the opossum into the trap, use a small trail of bait leading to the trap.

All traps should be checked in the morning and evening, so that captured animals may be dealt with in a humane manner.

Release the animal several miles.

Check with your game and wildlife department before trapping and releasing them.