Opossum

Opossums are marsupials of the order Didelphimorphia, found only in the Americas. It is the largest marsupial order in the Western Hemisphere, with 126 species in 18 genera. The Virginia opossum (Didelphis virginiana) is the only species found in the United States and Canada.

They are small to medium-sized animals that grow to about the size of a house cat. Most have long snouts, and many have a pouch in females. Some have prehensile tails, and the hind feet have an opposable toe with no claw. Males are usually larger and heavier than females.

Opossums live in forests, shrubland, mangrove swamps and rainforests across North, Central and South America. The Virginia opossum ranges from Canada down to Central America and is often found in wooded areas. They are opportunistic omnivores, eating insects, rodents, birds, eggs, frogs, plants, fruit and grain.

Opossums originated in South America, probably in the Amazonia region. The oldest fossils date from the early Miocene, roughly 20 million years ago. They entered North America in the Great American Interchange, after North and South America joined in the late Cenozoic.

The word opossum comes from the Powhatan language and was first recorded between 1607 and 1611 at Jamestown, Virginia. It ultimately comes from a Proto-Algonquian word meaning white dog or dog-like beast.

Until the early 20th century the Virginia opossum was widely hunted and eaten in the United States, and opossum farms have been run there. In parts of the Caribbean the meat is still popular, and opossum pelts have long been part of the fur trade.

Opossums are usually solitary and nomadic, staying in one area while food and water are easy to find. They are nocturnal and favour dark, secure spots. They may use abandoned burrows but put little effort into building their own.

When threatened or harmed, they may play possum. This is an involuntary response, like fainting. The lips draw back, the teeth show, saliva foams, and a foul-smelling fluid is released. The animal can be prodded or carried without reaction and usually recovers after a few minutes to four hours. Baby opossums often fail to do this.

They are typically nonaggressive. Threatened ones growl deeply, and males click as they search for a mate. Babies sneeze to call their mother. A mother sometimes carries her young on her back.

Opossums have an unusually short lifespan for a mammal of their size, usually only one to two years in the wild and as long as four or more years in captivity. Ageing is rapid.

Their young are born at a very early stage after only 12 to 14 days of gestation. Litters can have up to 20 young, but most fail to attach to a teat, and at most about 13 survive.

Many large opossums are immune to the venom of rattlesnakes and pit vipers.

This is general awareness only, not veterinary advice. If you find an injured or unwell wild animal, contact a vet or a wildlife rescue.

What is an opossum?

It is a marsupial of the order Didelphimorphia, native to the Americas. Females of many species have a pouch, and the young are called joeys.

How long do opossums live?

Usually only one to two years in the wild. In captivity they can reach four years or more.

Are opossums aggressive or likely to carry rabies?

They are typically nonaggressive and do not often transmit rabies.

Is an opossum the same as a possum?

In North America the Virginia opossum is commonly called a possum. Australasian possums look similar but belong to a different order.

Do opossums really play dead?

Yes, but it is an involuntary reaction like fainting, not a conscious act. It can last from a few minutes to four hours.

The water opossum, or yapok, is the only living semi-aquatic marsupial, and uses webbed hind feet to dive for freshwater molluscs and crayfish.

Opossums have 50 teeth, an unusually full jaw by mammalian standards.

An early colonist described the opossum as having a head like a swine, a tail like a rat and the bigness of a cat.

Some opossums use their tails as a fifth limb when climbing, or to carry bunches of leaves to the nest.

The order's name means double-wombed, referring to the female reproductive system.