Most female marsupials have a pouch in which they carry their babies. Short tailed opossums don't. Instead, the newly born babies attach to their mother's nipples which then enlarge and securely hold them in place against her stomach. Short tailed opossums are 4 to 6 inches in body length when full grown. They weigh between 3 and 5 ounces.
Males tend to be somewhat larger than females.
Their thick, velvety fur is usually gray-brown on top and lighter underneath. They have a prehensile tail used for balancing, as well as carrying bedding or other items. Unlike their North American cousins, it isn't weight bearing. Possum Pets Short tailed opossums have been kept as laboratory animals in the United States for many years, but it is only recently that they've become popular as pets. These inquisitive animals are extremely friendly when handled from a young age, but even well-tamed opossums can become panicked when you reach into their cage.