North American opossum
The Virginia opossum is the only marsupial found in North America north of Mexico. In the United States, it is typically referred to simply as a possum. It is familiar to many North Americans as it is often seen near towns, rummaging through garbage cans, or as roadkill. They are about the same size as a large house cat, having a triangular head with a long pointed nose. The fur is grayish and is everywhere except its ears, tail and feet. Amongst their fur are long white-tipped guard hairs. The fur color may differ according to the population’s range. Their ears are large and delicate and the tail is prehensile, adapted for gripping and wrapping around tree limbs.
Virginia opossums live in most parts of the United States that are east of the Rocky Mountains, and along the west coast from British Columbia in Canada and to Baja California. It is also found in Mexico and Central America. The animal lives in a wide range of habitats, including open woods, deciduous forests, and farmland. It prefers wet areas like swamps, marshes and streams.
Virginia opossums are nocturnal, solitary and terrestrial. They are very good climbers and may establish their dens in trees. They begin their nightly activities at dusk and are active until dawn. They don’t hibernate but do reduce activity during the coldest seasons. Denning sites vary and may include buildings, abandoned burrows and hollow trees. Virginia opossums change their denning sites often. They only remain in one den for a long period when weaning young.
These opossums are polygynous, which means that one male mates with multiple females. Breeding is typically from December to August. The brief gestation period is 12 to 13 days and up to 25 young may be produced in each litter. However, the total number that can be raised is determined by how many teats (normally 13) are in the pouch. The average number of young is typically 7 or 8. On entering the pouch, each baby must find a nipple and attach itself or it will die. The pouch young remain firmly attached to a nipple for their first 50 to 55 days. Around 85 days old they begin eating solid food and are weaned completely between 93 and 105 days. They reach sexual maturity within their first year of life, at about 6 months for females and 8 for males.
There are no major threats to this species. In some areas they can be trapped or hunted by humans but the main threat from humans is collision with motor vehicles.
The IUCN Red List and other sources do not provide the Virginia opossum total population size, but this animal is common and widespread throughout its known range. Currently this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are increasing.
These opossums are scavengers, making them very important in their habitat. By eating carrion, the risk of disease spreading in the area is lowered. They are important as seed dispersers, redistributing undamaged seeds from the genera Diospyros and Asimina, among others.