Eastern hog-nosed snake © Joe Crowley
Characteristics
The eastern hog-nosed snake (Heterodon platirhinos) has an unmistakable upturned snout, which gives this species its name. The coloration and patterning of this species is highly variable. Some individuals may have alternating dark blotches down the back and sides on a lighter background, which can be olive, tan, yellow, brown or grey. Others may lack patterning altogether and are a solid colour, usually olive or grey. Although the blotches down the back and sides may be absent on some individuals, a large blotch behind each eye is always present. This thick-bodied snake has a wide neck, which it flattens out (much like a cobra’s hood) during its defensive display. The scales of the eastern hog-nosed snake are keeled (ridged down the centre), and the underside of the tail is noticeably lighter in colour than the belly. These snakes can grow to just over a metre in length, though typically only reach 50 to 85 centimetres.
Eastern hog-nosed snake © Joe Crowley
Similar Species
In Ontario, the eastern foxsnake, massasauga and milksnake also have blotches running down the back and sides, and the northern watersnake can have faint banding. All these species, however, lack the upturned snout, which among Ontario snakes is unique to the eastern hog-nosed snake. It is also the only snake in the province that can flatten its neck into a “hood” as a cobra does.
Eastern hog-nosed snake © Emma Horrigan
Habitat
The eastern hog-nosed snake inhabits fields, forests, shrubland, beaches and old dune habitats. Along the eastern shore of Georgian Bay, it can also be found in forest clearings and rock outcrops, as long as other suitable habitat is available nearby. This species is generally found in habitats with sandy, well-drained soils, into which this snake burrows. It is commonly encountered on beaches due to its affinity for open, sandy areas.
View an interactive map of the known ranges of eastern hog-nosed snakes in Ontario.
Biology
The eastern hog-nosed snake breeds in the spring, late summer, or autumn. In June or July, females typically lay between 28 to 35 eggs, in burrows in sandy soil, which the snake excavates with its upturned snout. This species may also deposit eggs in rotting logs or under rocks or leaves. The eggs hatch after about two months, and the young are approximately 20 centimetres in length at birth. In Ontario, eastern hog-nosed snakes reach maturity after four or five years but in warmer climates may do so in as little as two years. Individuals can live up to seven years in the wild. Eastern hog-nosed snakes hibernate underground below the frost line, often in burrows that they excavate in sandy soil. This species is not known to overwinter communally.
The eastern hog-nosed snake uses very mild venom to immobilize its prey. As it swallows its prey, the snake injects its venom through fangs at the back of its mouth. This species cannot inject venom into larger animals such as humans unless allowed to hold on (e.g., to a hand or finger) for some time. Its venom is not dangerous to humans.
Eastern hog-nosed snake © Eugene Jankowski
Continued
When disturbed, the eastern hog-nosed snake will raise its head, flatten its neck as a cobra does, hiss loudly and lunge toward the threat. This snake keeps its mouth closed during these bluff strikes. If this impressive display does not scare away a potential predator, the snake may roll onto its back and play dead with its mouth gaping and tongue hanging out, emit a foul-smelling odour and sometimes defecate or regurgitate food. This behaviour is meant to deter predators that do not eat dead or rotten animals. If the eastern hog-nosed snake is turned over onto its belly, it will promptly flip onto its back and play dead again.
Other names: eastern hognose snake, Heterodon platyrhinos browni, Heterodon browni, Heterodon platyrhinos platyrhinos
Eastern hog-nosed snake © Emma Horrigan
Threats and Trends
The soil characteristics of hog-nosed snake habitat predispose those sites to conversion to agricultural fields and waterfront recreational areas. As a result, much of the historic habitat of the eastern hog-nosed snake has been destroyed in southern Ontario, and remaining habitat is under constant development pressure from these human land uses.
Human persecution is also a serious threat to this species. Uninformed people often kill eastern hog-nosed snakes, mistaking their defensive display for that of a dangerous species. These snakes often use beach habitats, which increases the potential for persecution because many people also use these areas. Road mortality is also a threat to this species, and high mortality rates have been documented on some roads in Ontario.
Eastern hog-nosed snake © Jessica Ferguson
Current Status and Protection
The eastern hog-nosed snake is currently listed as Threatened under both the Ontario Endangered Species Act, 2007 and the federal Species at Risk Act. The species has also been designated as a Specially Protected Reptile under the Ontario Fish and Wildlife Conservation Act. These acts offer some protection to individuals and their habitat. The International Union for Conservation of Nature lists the global status of the eastern hog-nosed snake as Least Concern. The species’ status was last confirmed in March 2007.
Learn more about reptile and amphibian conservation and what you can do to help these species on our Reptile and Amphibian Stewardship page.
Eastern hog-nosed snake © Joe Crowley
What You Can Do
- Report a sighting
- Get involved in reptile and amphibian conservation on your property, on the road and in your community
- Donate to support reptile and amphibian conservation
- Watch for reptiles and amphibians on the road
- Don’t release pet reptiles and amphibians into the wild
- Read more about the eastern hog-nosed snake in the Ontario Reptile and Amphibians Atlas publication.
Eastern hog-nosed snake © Jessica Ferguson