What are Opossums?
Opossums are the largest order of marsupials, having 103 species in the Western Hemisphere. Originally from South America, these animals entered North America with the connection of the two continents. They are successful survivors in many areas thanks to their flexible diet and reproductive habits.
Opossums are found throughout most of North America, and are considered an invasive species in southern Ontario and British Columbia.
Identification of Opossums
Opossums are small to medium sized, ranging from the size of a small mouse to the size of a large house cat. They have a narrow braincase with long snouts, and a prominent sagittal crest, which is a ridge of bone that runs lengthwise on the skull. Their feet stand flat on the ground (a plantigrade stance) and the back feet have one opposable digit with no claw. They also have prehensile tails, which means that the tail is used for grasping and holding things. They fur is made of only awn hairs, and the female opossums have pouches.
Opossums have incredible immune systems, and show partial to full immunity to rattlesnake, cottonmouth, and other pit viper venom. They are (surprisingly!) also 8 times less likely to carry rabies than wild dogs. About one in 800 total opossums is actually infected with the rabies virus.
Most species of opossums have adapted well to living both on the ground and in trees. Normally they are nomadic solitary animals, and may stay in one area as long as water and food are available to them. Sometimes families group together in burrows or under houses, and will not usually take the effort to build their own burrows. They are nocturnal and favor dark, occupying areas either above or below ground.
When opossums are threatened or in danger, they will “play opossum”, faking being dead by appearing so and omitting an odor similar to a dead animal. This is an involuntary response in adults, but the brain in a baby does not always react in this way. When doing this, an opossum will draw its lips back to expose the teeth and foam at the mouth. Their eyes will also be half closed, and they will remain stiff when poked and even turned over.
Removal and Preventative Procedures
The best way to keep an opossum out of a deck or patio (or under a house!) is to make sure they can’t get in there in the first place. Make sure all siding, screening, and barriers are securely in place to avoid intrusions. To see if an opossum has moved in under a deck or home; fill the hole leading in with dirt and leaves and other debris. If there is an animal dwelling under it, they will have to push the debris out of the way to enter and exit the dwelling. If it is not moved in a couple of nights, it is safe to assume there is no animal dwelling under, and the homeowner may go ahead with the preventative sealing of all entries leading under.
If an opossum has moved in, to keep her out the homeowner will need to wait until the animal leaves their den and close the opening with netting or straw, but loosely so that an animal can get out but one can’t get back in without a struggle. It is important to check for any young opossums before closing a hole, to ensure that they are not separated from their mother. An L shaped barrier provides underground protection that cannot be dug out.
Chemical Application and Pesticidal Removal of Opossums
There are natural alternatives that are opossum repellents, as opposed to using harsh chemicals. A mix of 1 cup molasses and a liter of water mixed up with a drop of dish liquid squirt onto fresh leaf growth will keep opossums from eating the plants. Mothballs will also draw opossums out from any area they have inhabited, as they do not like the smell. Mixing fresh garlic pieces in water and spraying on plants will keep opossums away, as well as the same method with hot peppers or hot sauce. If these things do not remedy the problem of opossums, it would be best to call a trapper that is registered with your local law enforcement. They do come out free of charge to humanely trap and release any nuisance opossums.
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