Asleep in a foothold caught in Nov.         Awake in a cage trap, caught in June

Damage:
Possums can do a variety of damage. From chewing, to tearing trash out of the garbage cans. They generally use other animals dens for their own homes. They will eat about anything, and are commonly refereed to as "grinners" in the trapping community because of their mouth full of teeth, always looking like they are smiling.
Description:
Opossums are North Americas only marsupial, or pouched mammals. An adult possum is about the size of a large house cat, and resembles a cream or gray colored rat with a pointed snout and a long, naked tail. The gray color is from the white guard hairs of black- tipped under fur. The ears are naked, black at the base and lighter at the tips. The female has fur lined pouch on the belly, similar to that of a kangaroo. The tail is prehensile, meaning it can be used to grasp branches or other objects. Opossums range in weight from 4-12 pounds but average about 6. At the same age males may be twice the size and length as females
Habitat:
Opossums are interspersed throughout most Iowa habitats, although they may prefer brushy areas near streams. Den sites include cavities in rocks, brush piles, trash heaps, hollow trees, fallen logs and old buildings.
Habits:
Possums are shy, secretive and primarily nocturnal. They tend to be somewhat nomadic, and have no fixed home range. Opossums when pursued, often climb trees in attempt to escape. A common means of defense is feigning death which is so characteristic that it is know as "playing opossum." The animal rolls over on its side, becomes limp, and shuts its eyes and lets its tongue hang out. The heart beat is slowed. This reaction is a brief nervous shock, but the animal quickly recovers and escapes at the first opportunity. Although neither sex is particularly active when the temperature is below 20 degrees F, females show greater tendency then males to "hole up" during very cold weather. Their feet are adapted for climbing and the opposable toe on the hind foot assists in holding onto small branches. They have the ability to support themselves entirely the tail if at least half of it grasps a branch.
Reproduction:
Most breeding occurs in February or March, but second peak in breeding activity occurs in late May through June after the first litters are weaned. A female may breed at either or both of these times. The average number of young is 9, but ranges from 5-13. Young are born blind and incompletely developed. Each is less then one half inch long and weigh 1/175 ounce. The young climb up a fur pathway into the pouch and attach to a teat for about 60 days as they continue to develop. At 60 days of age the young are about the size of mice, and the eyes are open. Young stay with the female for about 100 days. Breeding occurs the year following birth.
Food:
Possums are omnivores, and will eat almost anything.
Sign:
Possum tracks are very distinctive, especially the wide angled "big toe"(opposable thumb) on the hind foot. Opossum droppings are not distinctive and very according to the type of food eaten..
Predators:
Predators of opossums include dogs, people, foxes, coyotes and great horned owls.
Diseases:
Tularemia and rabies can occur in this species although little is known about diseases infecting opossums.
Parasites:
Parasites known to occur on or in opossums are mites, ticks, lice, fleas, roundworms, flukes and tapeworms