Opossums

´╗┐Identification | Biology | Damage ID | Management | Resources

Learning Objectives 

  1. Describe the behavior of opossums.  
  2. Communicate options for control to clients. 
  3. Describe the risks that opossums pose to animal health. 
Figure 1. Opossum (Didelphis virginiana) with young. Photo by Dave Schmidt.  

Identification 

Opossums (Didelphis virginiana, Figure 1) are the only marsupials (pouched mammals such as kangaroos and wombats) in North America. 

Legal Status 

Laws protecting opossums vary among states. Most states have open seasons for hunting or trapping opossums. Contact local wildlife authorities before removing opossums. 

Physical Description 

Opossums are about the same size as house cats, but can grow to a length of 40 inches. Their tail is rat-like, hairless, and slightly less than ┬Ż their total length. In northern climates, however, tail length may be shorter due to frostbite. Opossums may weigh as much as 14 pounds, but average is 4 to 12 pounds, with males generally larger than females. The color of their fur ranges from snow-white to jet-black. The underfur is dense with sparse guard hairs. Their face is long and pointed with a skull that is usually 3 to 4 inches long and holds 50 teeth, more than any other mammal in North America. Canine teeth (fangs) are prominent. The ears are rounded and hairless, and are prone to frostbite in the northern regions. The tail is moderately prehensile. Opossums have acute hearing but poor vision. 

Species Range 

Opossums are found in Eastern, Central, and West Coast states. They are absent from the Rockies and most Plains states (Figure 2). 

Figure 2. Distribution of the opossum in North America. Image by Prevention and Control of Wildlife Damage

Voice and Sounds 

When frightened, opossums hiss, growl, screech, and bare their teeth, depending on the level of threat that they perceive. Males and females signal each other during the breeding season with a clicking sound.  

Tracks and Signs 

Tracks of both front and hind feet look as if they were made by little hands with widely spread fingers (Figure 3).  

They are distinguished from tracks of raccoons because the hind foot of an opossum looks like a distorted hand due to the opposable big toe. Opossums can emit an oily yellow liquid from anal glands that smells like diluted musk of skunks. 

Figure 3. Tracks of a walking opossum. Hind foot is about 2 inches long and footprint is unique among North American animals. Stride is 6 inches. Image by PCWD.