Rattlesnake

ARTICLE CONTENTS:  |  Suggested Reading  |  Links to Other Sites
Rattlesnake is the common name for about 30 species of venomous viperid SNAKES in the genera Crotalus and Sistrurus, found from southern Canada to South America.

Description

Characteristic features include a broad, triangular head with movable fangs, a stout body and a "rattle" made of modified scales, each of which once capped the tip of the tail. The buzzing sound produced by rapidly vibrating the tail is believed to act as a defensive warning to intruders. Rattlesnakes are pit vipers (ie, have a heat-sensing pit on either side of the face).

Distribution and Habitat

Four species are native to Canada: the western rattlesnake (C. oreganous) occurs in arid grasslands of BC; the prairie rattlesnake (C. viridus) lives in similar habitats in Saskatchewan, Alberta and BC; the timber rattlesnake (C. horridus; extirpated in Canada) and the massasauga rattlesnake (S. catenatus) are restricted to southern Ontario. Rattlesnakes often hibernate communally in rocky outcrops.

Reproduction

Although massasauga rattlesnakes may mate in spring, mating in other species occurs in late summer; fertilization takes place the following spring. In early fall 2-10 (may be more in massasaugas) live young are born. Females reproduce only every 2-3 years. Diet consists mainly of rodents, other small mammals and birds.

Venom

The venom used to kill prey is a mixture of neurotoxins and hemotoxins (affecting nerve and blood tissues, respectively) delivered through the fangs. Rattlesnakes rarely strike humans, unless provoked or accidentally stepped on. The bite can cause painful swelling, muscular paralysis and tissue destruction, and may result in death. Less than 2% of all snakebites in North America are fatal if given medical attention. The incidence of snakebite in Canada is low.

Rattlesnake, Video
(courtesy Karvonen Films)
Rattlesnake
Rattlesnake
Three species are native to Canada: the western rattlesnake in arid western grasslands, the timber rattlesnake (probably extirpated) and massasauga rattlesnake in southern Ontario (Corel Professional Photos).

Author J. MALCOLM MACARTNEY Rev: PATRICK T. GREGORY


Suggested Reading
Carl H. Ernst and Evelyn E. Ernst, Snakes of the United States and Canada (2003); Harry W. Greene, Snakes: The Evolution of Mystery in Nature (1997).


Links to Other Sites
Canadian Biodiversity Website
A great information source for all budding biologists. Learn about biodiversity theory, natural history, and conservation issues. From McGill’s Redpath Museum.

Why survey Herptiles?
This Parks Canada website is devoted to the study of amphibian and reptilian species native to Canada.

0
0
Absolutely free, with over 40,000 articles in French and English, The Canadian Encyclopedia is the ultimate online resource for all things Canadian, from history, sports, arts, science, technology, and much, much more. Get started at www.TheCanadianEncyclopedia.com
Feature Articles
Maisonneuve and the Founding of Montreal

The story of the founding of Montreal is perhaps unique in history....

INSIDE TCE

Gallery
Browse the rich visual resources of The Canadian Encyclopedia through thematic galleries of Canadian Art, History, Nature, People, and Science and Technology.
Interactive Resources
Illustrations, lively text, animations, sounds and games help make learning about Canadian history, art, geography, architecture and other topics entertaining as well as informative.
Canucklehead
The ultimate test of your knowledge of Canada, trivial and otherwise. You can choose from more than 60 dynamic quizzes with visual or text clues. Your scores depend on the speed with which you answer and the number of clues you need. Results are sent to you by email and high scores are posted on the site.
Timeline
This unique resource includes more than 6000 events from Canadian and world history. It can be searched by era, subject, keyword or date. To find out what happened on your birthday, select the month and day of your birth.
100 Greatest Events
This selection of the 100 "greatest" events in Canadian history was made by editor in chief James H. Marsh to draw attention to events that have left an indelible memory in the minds of later generations.