Opossums usually live alone, having a home range of 10 to 50 acres (4 to 20 ha). Young appear to roam randomly until they find a suitable home range. Usually they are active only at night. The mating season is January to July in warmer parts of the range but may start a month later and end a month earlier in northern areas. Opossums may raise two, rarely three, litters per year.
The opossum is the only marsupial in North America. Like other marsupials, the blind, helpless young develop in a pouch. They are born 13 days after mating. The young, only 1/2 inch (1.3 cm) long, find their way into the female’s pouch where they each attach to one of 13 teats. An average of seven young are born. They remain in the pouch for seven to eight weeks. The young remain with the mother another six to seven weeks until weaned.
Most young die during their first year. Those surviving until spring will breed in that first year. The maximum age in the wild is about seven years.
Although opossums have a top running speed of only 7 miles per hour (11.3 km/hr), they are well equipped to escape enemies. They readily enter burrows and climb trees. When threatened, an opossum may bare its teeth, growl, hiss, bite, screech, and exude a smelly, greenish fluid from its anal glands. If these defenses are not successful, an opossum may remain motionless in the hopes the threat will leave.
When captured or surprised during daylight, opossums appear stupid and inhibited. They are surprisingly intelligent, however. They rank above dogs in some learning and discrimination tests.
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Opossum
