Opossums are nocturnal and solitary animals known for their tree-climbing ability. They live for seven years on average and mate during the spring and summer seasons. They have 50 sharp teeth and eat insects, small animals, fruits, vegetables, lizards and garbage.

As they lack adaptation for food storage and their ears and tails are vulnerable to frostbite, they invade underground dens of other animals during the winter. They’re also often found foraging for food during the day.

How opossums behave

Opossums are born naked and half an inch long inside their mothers’ pouch without fully developed organs.

They are nursed for 60 days in the pouch and another 30 to 40 days outside the pouch. After about 120 days, they become independent and disperse. When separated from their parents before this stage, they make a sneezing noise for their mother to hear.

When opossums feel threatened, they don’t run away. Instead, they expose their mouths and teeth and drool saliva.

In some cases, they may growl or hiss, emit a foul-smelling greenish liquid from their anal glands, and defecate. Finally, they may drop to its side and play dead until the threat is gone.

Male opossums can become aggressive during mating season, especially when they feel threatened. They may growl and charge aggressively at an opponent, trying to bite them in some cases. 

What to do when you encounter an opossum

Opossums can be found up in trees, as they often climb to search for food or safety. They can also be found in people’s yards and nearby homes and woodpiles. In such cases, it’s best to leave them alone.

While they are not known to carry rabies, their bites can be infectious due to their diet. They can also carry typical parasites.

We recommend you to keep children and pets away when you encounter opossums. Within 24 hours of the encounter, they should have moved on.

If the opossum does not leave the premise and shows signs of aggression, do not approach it. Instead, contact Mississauga Animal Services for support.

How to report ill or injured opossums

If opossums are ill or injured, you may notice:

  • External tumours or abscesses on their body (common)
  • Injury or open wounds
  • That they have not moved for many hours or overnight
  • Eyes or nose caked with mucous

If you encounter an opossum with minor injuries, you can contact a licensed Wildlife Rehabilitator.

If you see an opossum with critical or life-threatening injuries, you can call Mississauga Animal Services at 905-896-5858 for support.