The Virginia opossum is the only marsupial found in North America and a common sight across the continent, often moving nocturnally through backyards and wooded areas. Identifying their presence can be challenging, but they leave behind distinctive tracks for those who know what to look for. Recognizing these unique prints requires understanding the opossum’s specialized foot structure and characteristic walking pattern. These details allow for clear identification of opossum activity in mud, snow, or soft soil.
Unique Anatomy of Opossum Feet
The most telling feature of an opossum track comes from its unusual hind foot anatomy. Opossums possess five digits on both their front and hind feet, a feature they share with a few other small mammals. The defining characteristic is the specialized inner toe on the hind foot, known as the hallux, which acts as an opposable thumb.
This opposable hallux is large, widely separated from the other four toes, and is entirely clawless. This structure gives the hind print a distinctly hand-like appearance, allowing the animal to grasp branches securely while climbing. Because the toe rotates outward for grip, its print almost always angles away from the direction of travel, often at nearly a 90-degree angle to the rest of the foot. The opossum’s plantigrade posture, meaning it walks on the entire sole of its foot, contributes to a larger, flatter print.
Visual Characteristics of Front and Hind Tracks
The front and hind prints of an opossum differ noticeably in both size and shape, which is a significant clue for identification. The front track is smaller, typically measuring around two inches in length and width. This print shows five splayed toes that radiate outward, giving it a somewhat star-like appearance, though without the specialized thumb.
The hind track is larger and more distinctive, often measuring about 2.5 inches long and 2.3 inches wide. The four main toes of the hind foot point forward, while the print of the large, thumb-like hallux juts out to the side. This opposable toe print lacks a corresponding claw mark, which helps distinguish it from other five-toed tracks, such as a raccoon’s. The combination of the smaller, splayed front print and the larger, thumb-marked hind print is unmistakable.
Opossum Walking and Movement Patterns
The way an opossum moves creates a predictable pattern that confirms track identification. Opossums generally use a “pacing” or “waddling” gait where the front and hind limbs on the same side of the body move nearly simultaneously. This diagonal walk often results in a staggered or uneven trail.
The hind foot commonly lands next to or slightly ahead of the opposite side’s front foot, creating an alternating pattern. In soft terrain, the print sequence often shows the hind foot landing just behind or partially overlapping the front foot from the same side. This close proximity can sometimes make the double print look like the track of a much larger animal. The trail width is generally narrow, and in deep mud or snow, a faint, straight drag mark from the long, prehensile tail may be visible between the track sets.