The only pit vipers found in Canada are rattlesnakes.  Rattlesnakes 
are venomous and their bite can be lethal.  We do not encourage anyone 
to try catching rattlesnakes, but it is valuable to be able to identify 
them from other non-poisonous snakes in the field.  Keep in mind that 
many non-rattlesnakes will vibrate their tails in leaves, mimicking the 
sound of a rattlesnake. 


Choose the description that best fits the animal of interest.
If none fit go back to previous page.
   
A. Large rattlesnake (grows to over 1 m), head unmarked, dark 
back and side blotches on front of body with blotches fused to 
form crossbands on the rear of the body, tail black, was only 
found in southern Ontario and now extirpated.
             
             Crotalus horridus (Timber Rattlesnake)



B. Large rattlesnake (grows to over 1 m), head may be patterned, 
on the prairies it is generally light brown with well defined dark 
brown blotches, in British Columbia it is dark, sometimes 
almost black with large dark blotches partially bordered with 
white scales.
             
             Crotalus viridus (Western Rattlesnake)


C. Small rattlesnake (less than 1 m), unlike other rattlesnakes 
has 9 enlarged scales on top of head, dark bar extends from eye to 
rear of jaw, dark bars on top of head extend onto neck, rounded 
dark blotches on back and sides with narrow interspaces.
             
             Sistrurus catenatus (Massasauga)