The Virginia opossum (Didelphis virginiana) is the only marsupial found north of Mexico. This article explores their typical dimensions and the factors influencing their size.
Typical Possum Dimensions
Adult Virginia opossums typically have a body length of 33 to 55 centimeters (13 to 22 inches) from snout to tail base. Their prehensile tail adds 25 to 54 centimeters (9.8 to 21.3 inches), bringing the total length to 2 to 3 feet (24 to 36 inches).
Adult female opossums generally weigh 1.9 to 2.1 kilograms (4.2 to 4.6 pounds), while males are slightly heavier, at 2.1 to 2.8 kilograms (4.6 to 6.2 pounds). Some individuals can be considerably larger, with reported weights up to 6 kilograms (14 pounds). Males tend to be the heavier and longer individuals.
Factors Affecting Possum Size
Several elements influence the size an individual Virginia opossum can attain, beginning with its age. Opossums develop rapidly, reaching a near-adult size by around six months of age and are typically considered fully grown between seven and eight months. While their length growth may slow, they can continue to gain weight as they mature.
Sex also plays a role, as male opossums are generally larger and heavier than females. For instance, male Virginia opossums can reach an impressive total length of up0 to 100 centimeters (40 inches), whereas females usually average about 72 centimeters (28 inches). Older males, especially in the fall, can even exceed 6 kilograms (13.2 pounds) as they store body fat.
The availability and quality of food significantly impact an opossum’s size. As opportunistic omnivores, Virginia opossums consume a wide variety of foods, including fruits, insects, small animals, and carrion. Opossums living in urban environments often grow larger, with some studies indicating they can be approximately 34% heavier than their rural counterparts due to easier access to food sources like pet food and garbage. Geographical location also contributes to size variation, with larger specimens typically found in the northern parts of their range, while those in tropical regions tend to be smaller. Northern populations also possess denser underfur compared to the thinner fur of southern populations, which influences their overall appearance.
Identifying a Large Possum
Beyond numerical measurements, a large Virginia opossum can be identified by several visual characteristics. These animals typically possess a robust body build, giving them a substantial appearance. Their short legs and stout physique contribute to this sturdy impression.
A key feature is their long, thick, and muscular tail, which is scaly and mostly hairless. This prehensile tail, used for gripping and balance, can appear quite substantial on a larger individual. A full, dense coat of dull grayish-brown fur, often interspersed with longer white hairs, also contributes to the perception of size. Northern opossums, in particular, may exhibit a more grizzled look due to lighter guard hairs and thicker underfur, making them appear more imposing. Males, when fully mature, might also display a slightly rounder head shape and a yellowish stain on their chest fur from scent glands, providing additional cues to their larger stature.