The Virginia opossum is one of the few animals in North America that routinely eats venomous snakes and survives the bites. A protein in its blood called von Willebrand factor has mutated at the exact site where pit viper venom normally attaches, giving the opossum roughly a hundredfold increase in resistance over any other mammal its size.
In 1977, researchers injected opossums with 60 times the dose of rattlesnake venom known to kill a dog of similar weight. They monitored them for 30 days. Nothing happened.
Published prey records for the Virginia opossum include copperheads, cottonmouths, timber rattlesnakes, eastern diamondbacks, western diamondbacks, watersnakes, racers, milk snakes, ring-necked snakes, garter snakes, and brownsnakes. A 1954 Texas diet study found copperheads alone made up about 6 percent of opossum prey. A 1950 New York study found snakes of all species made up 19 percent.
The opossum grabs whatever part of the snake it reaches first and starts chewing right away.
The 2026 Edwards and Balchan paper documented an opossum spending 20 minutes working on a snake from the tail end without ever moving toward the head. It does not need to be careful about which end it starts with because the venom cannot hurt it. A copperhead biting an opossum on the face while being eaten alive is delivering a weapon that the opossum's blood neutralizes before it reaches any organ.
This happens every night across the eastern and central United States, wherever brush, cover, and water meet, and nobody sees it because the opossum is nocturnal. The animal's body temperature runs 94 to 97 degrees, low enough that rabies rarely takes hold because the virus struggles to replicate in a cool host. It has 50 teeth, more than any other North American land mammal, arranged in a jaw built to grip struggling prey and not let go.
The widely repeated claim that a single opossum eats 5,000 ticks per season came from a 2009 Cary Institute study that extrapolated from laboratory grooming trials, and subsequent field research has not confirmed the number.
An opossum living under a porch, a deck, or a crawl space is patrolling the property between midnight and dawn, eating the snakes it encounters along the foundation, the garden edges, and the gaps where the lawn meets the brush.
Image is for illustration purposes only
Source: Werner and Vick (1977), Toxicon / Jansa and Voss (2011), PLOS ONE / Edwards and Balchan (2026), Reptiles and Amphibians / Hamilton (1950) / Wood (1954) / Cary Institute of Ecosystem Studies.