What is it Wednesday: Eastern Hog-nose Snake

Name: Eastern Hog-nosed Snake (Heterodon platirhinos)

The Eastern Hog-nosed snake is one of the most fascinating snakes in Ontario. The colours of the snake range from a grey and brown striped pattern to a blotchy yellow-orange and black, like that of the Fox snake, to a solid blue-grey, like the Blue Racer snake. The Eastern Hog-nosed snake also mimics the shape of the Massasauga Rattlesnake with a fat body and can reach lengths of about 1 meter long.

The Eastern Hog-nosed snake continues its mimicry of many other snakes in its multiple defense mechanisms. It’s first tactic is to lie motionless and depend on its camouflage to disguise itself. Failing this, it will puff out its neck, like a Cobra or Puff Adder, raise its head up and stand in a striking pose. Similar to a rattle snake, it will start to rattle its tail while holding its striking pose. Then it will strike, while keeping its mouth closed. This is all a bluff as its venom cannot affect anything larger than a small mammal. Its last tactic is to play dead. The snake will flip onto its back, exposing its belly and lie there with its mouth open and tongue hanging out. To top it all off, it will release a foul-smelling odour or even regurgitate its food. This is to deter predators that avoid rancid or decaying meals. It’s as if this snake is trying to take the identity of every other snake in the world.

What is unique about the Eastern Hog-nosed snake is their upturned snout, the defining characteristic for which they are named. They will use this upturned snout to dig up a nest in sandy soil for food or to bury itself.

The main food source for the Eastern Hog-nosed snake are toads. Toads are well known for their self defense mechanism of peeing when threatened, surely an unpleasant taste for a snake. However, toads also have a defense mechanism of inflating themselves so that they are harder to swallow by snakes. The Eastern Hog-nosed snake has a way to overcome this. The snake has small fangs at the back of its mouth that are mildly venomous (not to humans) that will puncture the toad to deflate it. This allows the snake to swallow its prey. While toads comprise about 50% of their diet, they will also munch out on frogs, salamanders, small mammals, birds, and invertebrates.

This fat bodied snake can be found throughout Eastern North America, with about 10 percent of its habitat resting within Canada. It needs a mosaic of different habitats to survive such as fields, forests, shrubland, beaches and old dune habitats. Traveling up to 100 meters a day between these habitats they often will cross roads or come into contact with humans. This is where the Eastern Hog-nosed snake runs into trouble.

The Eastern Hog-nosed snake is considered “threatened” by the endangered species act, which means it receives protection on the federal and provincial level. Habitat loss is a major factor for why this species is threatened. They need large areas for their habitats and most of it has been turned into residential or farmland. As they travel in between these habitats they often will cross roads, which leads to a high mortality rate from being hit by cars. The other threat is from persecution by humans. These snakes tend to inhabit areas where humans will come across them and their multitude of defense mechanisms make them appear as a dangerous species. As humans instinctively fear snakes, they often will kill the Eastern Hog-nose snake when they come across it.

The Eastern Hog-nose snake continues to have a good chance of surviving as a population, but it will take educating the public not to fear these snakes, habitat protection/creation, as well as creating appropriate mitigations on roadways to protect them from road mortalities.


Thought provoking question: One of the defence mechanisms for the Eastern Hog-nosed snake is to puff out its neck and hold itself in a striking pose, quite similar to the King Cobra and Puff Adder. Although a striking pose is a common sign of aggression in snakes, the flattening of the neck is unique among North American snakes. Why would this behaviour evolve in the Eastern Hog-nosed snake if the Cobra and Puff Adder is on the other side of the world?