What Do Opossum Droppings Look Like? Opossum infestations can often be identified by the droppings the pests leave behind. Most opossum droppings are around 3/4 of an inch in diameter and taper off at the ends. Opossum feces are roughly one to two inches in length, smooth on the sides, and may have white or yellowish mold growing on the outer casings. Otherwise, opossum droppings are brown in color. The fecal matter also tends to curl as the animal excretes the waste. Health Hazards Like most animal scat, opossum dung often contains bacteria such as Salmonella and leptospirosis. Opossums are also known to carry the highly infectious Equine Protozoal Myoleoncephalitis (EPM), which attacks the nervous system of horses. The presence of opossum droppings should be taken seriously and handled with extreme care to avoid contamination. Opossums are notoriously aggressive creatures that go to great lengths to defend their dens and young. To ensure the safe removal of opossums and their droppings, contact a local pest control specialist, like those at Critter Control, who are trained and certified to handle these problems.