Virginia Opossum: Didelphis virginiana
In the Wild
Description:
Size: Body length of 13-22 in. (33-55 cm), and a tail length of 10-22 in. (25-55 cm)
Weight:
o Males: 4.6-6.2 lbs. (2.1 to 2.8 kg)
o Females: 4.2-4.6 lbs. (1.9 to 2.1 kg)
Sexual dimorphism: Males may be slightly larger than females
Medium-sized marsupial with grayish-black fur and a lighter gray-white face
Have large ears and a long, thin, mostly-hairless tail
Habitat and Range:
Are currently found in Central and North America from Costa Rica to southern Ontario,
Canada
Live in a variety of habitats, particularly in areas near water, such as a swamp or in
woodland areas nearby a stream
Prior to European settlement in America, the furthest north they lived was Ohio,
Kentucky and Indiana – their range is thought to be expanding further and further
northward as a result of their ability to survive the cold winters by living in developed
areas
Diet:
Omnivorous and opportunistic: Eat a wide variety of foods including vertebrates,
invertebrates, plant material, fruits, seeds, grains, carrion and food from trashcans
During the colder seasons, small vertebrates tend to make up a larger portion of their
diet, whereas in the warmer seasons, they consume more invertebrates, plant material,
fruits and seeds
Are commonly found raiding trash cans or chicken coops
Adaptations:
Have a long, prehensile tail and opposable first digit on their feet for climbing and
clinging in trees
Females have a pouch where newborns are protected while they develop and nurse
Have an epipubic or “marsupial” bone protruding from the pelvis to help support the
pouch
Are immune to the venom of a variety of snakes including rattlesnakes, copperheads,
cottonmouths and moccasins
Are able to live in urban areas due to their small body size and nocturnal habits
Are able to survive in extreme heat by spreading their saliva to cool down
Have a keen sense of smell and may also rely on touch to find food in the dark
Young individuals sometimes deter predators by pretending to be dead (sometimes
called “playing opossum”) – are able to remain completely still in the fainting state for
less than a minute or up to 6 hours
Adults typically bare their teeth and stand their ground or run away from predators
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The Maryland Zoo in Baltimore
Virginia Opossum: Didelphis virginiana
Use olfactory and auditory signals to communicate with their young, mates and
potential aggressors
o Scent glands in the mother’s pouch may assist newborns in finding the pouch
o Males have a scent gland on their chest which emits a musky odor and stains
their fur during the breeding season
o Females are able to call to their young using a series of clicks, lip smacking and
bird-like sounds
o When threatened, they may hiss, growl or screech
Lifespan:
About 1.5-4 years, have been reported living as long as 10 years in captivity
Young opossums have a very high mortality rate – most newborns never arrive in their
mother’s pouch and about 60% of those who do reach the pouch do not survive long
after they are weaned
Ecosystem relationships:
Predators: Owls, domestic dogs, coyotes, red foxes, raccoons, bobcats, large snakes and
humans
Are important seed dispersers
Reproduction:
Individuals become sexually mature around 6 months for females and 8 months for
males, but typically begin breeding around 10 months of age
The breeding season varies geographically – in more northern climates they breed from
February to September but in the southern areas they breed from January to August
Have a polygynous mating system – males mate with multiple females
After mating, males depart and do not assist with raising the young
The number of litters per year varies geographically – individuals in northern areas
reproduce only once per year, whereas individuals in southern areas may produce 3
litters in a year
Females nest in a variety of areas, including brush piles, trees and drainage areas
Females give birth to about 15 young (can range from 4-25 young) after an extremely
short gestation period of 12-13 days
The young are born very early in development and are about the size of a honey bee but
are able to climb into their mother’s pouch – on average, only about 8 young survive the
climb to the pouch
The offspring remain in the pouch for about 2 months where they nurse and continue
developing
When offspring leave the pouch, they remain with their mother for about another
month, often clinging to her back or remaining in the den while she forages
Activity:
Nocturnal
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The Maryland Zoo in Baltimore
Virginia Opossum: Didelphis virginiana
Terrestrial, but are also adept climbers and sometimes den in trees
Typically live solitary lives, except during breeding season and when mothers are
carrying young
Do not hibernate, but typically reduce their activity during extremely cold months
Other “fun facts”:
Opossum is an Algonquin Indian name meaning "white animal"
Also sometimes called the common opossum
Are the only North American marsupial
Marsupials are a group of mammals which share their reproductive strategy – young are
born very early in development and continue to develop in their mother’s pouch
Conservation Status and Threats:
Listed on the IUCN Red List as Least Concern – their ability to adapt to human altered
habitats has made them extremely successful and their range is thought to be
expanding as a result of their adaptability
Threats:
o The largest threat they face is collision with cars
o Are sometimes hunted for sport and for food – their pelts are sometimes sold
commercially
o Some cultures also believe their meat has medical properties – the meat is
thought to prevent heart attacks and to treat inflammation, colitis, gastritis, skin
infections, epilepsy, allergies, dermatitis and coughing
o Although it is illegal in many states, they are sometimes kept as pets
o Are often seen a pest species since they often root through trashcans, eat pet
food left outside and sometimes eat chickens
At the Zoo
Percival (Percy) is an orphaned male who was rescued from Druid Hill Park by Animal Control. It
is estimated that he was born around February 2013.
What We Can Do
Make environmentally responsible lifestyle decisions to help conserve habitat –
conserve energy, reduce litter and pollution
o To keep opossums out of developed areas, always keep lids on trashcans
o Litter on the side of the road may attract opossums, causing collisions – reducing
litter may prevent road mortality
Do your research before buying a pet – opossums do not make good pets
o They require a very particular diet and will get sick if they do not have the proper
nutrition
o Captive opossums are highly prone to illness and it is very difficult and expensive
to find a veterinarian who can and will care for a pet opossum
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The Maryland Zoo in Baltimore
Virginia Opossum: Didelphis virginiana
o They need a lot of exercise to prevent obesity and to keep them healthy –
owners would have to exercise them at night since they are nocturnal
References:
http://animaldiversity.ummz.umich.edu/accounts/Didelphis_virginiana/
http://www.iucnredlist.org/details/40502/0
http://www.seaworld.org/animal-info/animalbytes/animalia/eumetazoa/coelomates/deuterostomes/chordata/craniata/mammali
a/didelphimorphia/virginia-opossum.htm
http://www.opossum.org/
MacDonald, David W. (Ed.). (2006). Marsupials. The Princeton encyclopedia of
mammals. (pp. 8-19). Princeton, New Jersey: Princeton University Press
08/14/2013
The Maryland Zoo in Baltimore