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Sistrurus catenatus catenatus
It is the only venomous snake species in Ontario, and although its venom is potent, this is a small snake with small fangs and a limited amount of venom. Snake bites are rare; approximately 2-3 per year and with treatment, a full recovery is highly probable.
If you see or hear a rattlesnake, simply leave it alone! If you give the snake room it will retreat.
COSEWIC Status: Threatened
COSSARO Status: Threatened
- Medium-sized snake (50 to 76 cm.) with a thick body.
- Thick tail does not taper to a point and ends with a distinct segmented rattle. Rattle segments are added when the snake sheds its skin.
- Neck is narrow in contrast with the wide head and body.
- Bow-tie shaped dark brown blotches along back with two or three rows of spots along sides, grey background colour, dark belly.
- Dark lines extend from eyes to neck, vertical pupils (cat-like), heat sensitive pits between nostril and eye.
- May live in captivity for up to 20 years.
- Small mammals including voles, mice and shrews.
Habits and Reproduction
- Hibernates below the frost line from October to mid-April. A rock fracture, root pocket or rodent burrow provides a suitable site. In eastern Georgian Bay, these sites are often associated with damp areas or wetlands.
- Emerge from hibernation in late April.
- Uses venom to subdue prey.
- Shy, secretive, non-aggressive snake. Relies on camouflage and remaining still to avoid predators.
- Heat sensitive pits on head allow it to sense warmth in the vicinity while hunting under the cover of darkness.
- They reach sexual maturity at age 4 or 5 and mate mid to late summer.
- A female may reproduce every 2nd or 3rd year. Pregnant females will seek out “gestation” sites. These sites provide safe cover and a good range of temperatures so they can incubate their young. In our area, “table” rocks are often the preferred sites and a female will return to the same site each time she is pregnant.
- The average litter is 12, and the young are born usually in August.
- Newborns are 20-25 cm long and similar to adults but lighter in background colour. Their rattle is yellowish in colour. The fangs and venom are present at birth.
- Found in rocky scrub habitat, damp lowlands, open woodlands, bogs, and fens.
- Habitat loss particularly of important habitat such as hibernation sites, road mortality and direct persecution are the greatest threats to this snake.
- For more information on how to prevent and treat rattlesnake bites –Snake Saftey Tips.
- Guidelines for identifying important Massasauga Rattlesnake habitat are available at Parry Sound OMECP.
- Safety note regarding the use of silt cloth.
- How to safely move a rattlesnake.
Do You Work Outdoors?
- A “Working in Massasauga Habitat” DVD is available. Please contact us for a copy.
Newborn Massasaugas Credit: Jeremy Rouse
Table rocks provide female Massasaugas with a safe place to incubate their young. Credit: Jeremy Rouse
For more information about the Massasauga Rattlesnake in the Georgian Bay area, contact:
Ministry of Natural Resources and Forestry
7 Bay Street
Parry Sound, Ontario
Georgian Bay Islands National Park
901 Wye Valley Road