Habitat
Bushmasters
are found in relatively cool, moist tropical forests from mountainous
areas to coastal lowlands. Bushmasters
are native to southern Central America and almost all the northern
half of South America. The range of the two Central American subspecies
begins in southern Nicaragua and continues south to northern Colombia.
The two southern subspecies are found from central Colombia to central
Bolivia, extending from the eastern half of Ecuador and northeastern
Peru to the coastlines of northern Brazil, Guyana, French Guiana and
Surinam. They are also found on the island of Trinidad and along the
southern coast of Brazil. |
Physical
Characteristics
This species is the largest of all venomous snakes in the Americas
and the longest viper in the world, sometimes reaching a length of
12 feet (3.6 m). As with other members of its subfamily, the bushmaster
has hinged fangs that lie flat on the roof of the mouth when not
in use. Because of this adaptation, their fangs can be very long,
reaching as much as 1.4 inches (35 mm) in a large individual. Their
bodies are slightly flattened, with broad, wedge-shaped heads and
a short tail ending in a bony spur. When agitated, they may shake
their tail tip against foliage to make a threatening sound. They
have a light tan background color with large, darker brown to black
diamond-shaped patterns on their backs. Their scales are bumpy, with
a pronounced ridge of hard, sharp scales running down the center
of their back. The bushmaster is a
potentially dangerous snake to humans. Their venom kills by causing
internal bleeding. It is fairly weak compared to that of other
closely related species, but the bushmaster is able to produce
very large quantities of venom. The species is elusive, however,
and rarely encountered by humans. As a result, there have been
very few recorded human fatalities from bushmaster bites.
|
Life
Span
Life span in the wild is unknown.
In captivity, they typically live 12-18 years, with a recorded maximum
life span of 24 years. |
Diet
In the wild: Primarily
small mammals.
At the zoo: Domestic rats |
Reproduction
The bushmaster is an oviparous species, which means
they lay eggs rather than bear live young. The bushmaster is the only egg-laying
pit viper in the Americas.
Bushmasters
are solitary except when mating. Males find receptive females by
following scent trails left by females. Finding a female, he rubs
his head and flicks his tongue along the sides of her body to state
his intentions and make sure she is receptive. If so, he flips his
body upside down on top of hers and rubs his spinal ridge back and
forth in a sawing motion against her body to stimulate her. If she
is coiled up, he may also strike her with the side of his body to
encourage her to loosen her coils and allow him access. When she
uncoils, they wrap their bodies around one another and mate in that
position, sometimes remaining together for five or more hours.When
a female bushmaster is ready to lay her eggs, she finds a burrow
built by another small animal to claim as her own, sometimes sharing
the burrow with the animal that built it. She then lays eight to
12 eggs, each of which is white and slightly larger than a chicken
egg. After laying her eggs, the female coils her body around them
and guards them until they hatch 76-79 days later. She will not leave
her eggs even to hunt during this period.
Life
Cycle
Newborn bushmasters are about 20 inches (50 cm) long. They are pale-colored,
with a bright orange or yellow tail tip they gradually lose as they
get older. This may help the young bushmasters attract small, insectivorous
mammals to eat. The colors of the young bushmaster will usually change
to their dark adult pattern when the snake is between 1-2 years old.
Sexual maturity is typically reached around 4 years.
Feel the Heat
The bushmaster, like other pit vipers, has a special adaptation that
helps them detect their warm-blooded prey. They have two heat-sensitive
pits, one on each side of their heads, halfway between their eye
and nostril. These pits allow the snake to sense the heat difference
between a small mammal and the cooler rocks, plants and other objects
in the area. When a warm-blooded animal ventures closer than 20
inches (50 cm), the bushmaster can detect the prey entirely by
its body heat, even aiming its strike without any other sensory
information.
|
Fascinating
Facts
- Bushmasters produce an enormous amount of
venom. The average yield of dried venom from a bushmaster
is 411 mg (0.014 oz), compared to just 52 mg (0.0018 oz)
from the copperhead!
- Their
heat-sensitive pits allow a bushmaster to detect a heat difference
of just 0.0036° F (0.002°C)!
|
Woodland
Park Zoo’s
bushmasters are located in the Tropical Rain Forest. As visitors
enter the exhibit, they are immersed in a garden of tropical rain
forest plants such as fan palms, bananas, cocoa, figs and hanging
liana vines. The bushmasters can be found in the forest floor section
of the building.
The population of bushmasters in the wild is unknown,
due to their secretive habits and the dense forests and difficult
terrain they typically inhabit. The extensive degradation and destruction
of the tropical rain forests of South America is a major threat to
this and many other plant and animal species.
Humans need snakes!
By preying upon rodents and insects that eat our crops and spread
diseases, snakes help to control populations of these rapidly breeding
animals, keeping them within the carrying capacity of their habitats.
Snake venom is used in medical research on blood clotting, and to make
certain anesthetics and medications.
How You Can Help!
The effort to save endangered species requires cooperation and support
at the international, national, regional and individual levels.
You can help in this cause. Join and become active in Woodland
Park Zoo and other conservation organizations of your choice. Please
do not buy products made from wild animal parts. Contact your elected
representatives and express your views about conservation of endangered
species and wild habitats.
To
learn other ways you can help, contact Woodland Park Zoo at webkeeper@zoo.org about supporting conservation programs
at the zoo. Discover more about snakes by contacting the Society
for the Study of Amphibians and Reptiles at 303 W. 39th St., PO Box
626, Hays, KS 67601, or the American Federation of Herpetoculture:
AFH, P.O. Box 300067, Escondido, CA, 92030-0067. Learn other ways
you can help conserve wildlife and habitats by visiting our How You Can Help page.
Reptiles as Pets
We do not recommend reptiles as pets for most people as they require very specialized diets and environments. We also receive hundreds of requests each year to take former pet iguanas, boas and other reptiles but we cannot accept these due to space, health and unknown backgrounds. If you need to find a reptile or amphibian a new home, we suggest you contact a local herpetological group in your area. In the Puget Sound region, it is the Pacific Northwest Herpetological Society.
Sources and Suggested Reading
Bauchot, Roland (Ed.). 1997. Snakes: A Natural
History. Sterling Publishing Co., New York, NY. 220 pp.
For Kids!
Clarke, Dr. Barry. 1993. Amphibians. Eyewitness Books, Alfred A. Knopf,
Inc., New York, NY 64 p.
Matero, Robert. 1993. Snakes. (Eyes on Nature
Series). Kidsbooks, Inc., Chicago, IL. 29 pp.
More References
Burton, Maurice 1975. Encyclopedia of Reptiles, Amphibians and Other
Cold-Blooded Animals. BPC Publishing Ltd., San Sebastain, Spain.
229 p
Grzimek, Bernard 1975. Grzimek's
Animal Life Encyclopedia Vol. 6: Reptiles. Van Nostrand Rheinhold
Company. New York, NY. 468 p. EMBL Reptile
Database. (07/06/01)
Engelmann, Wolf-Eberhard and Fritz Jurgen
Obst, 1982. Snakes: Biology, Behavior and Relationship to Man.
Exeter Books, New York, NY. 222 p.
Ripa,
Dean. 1994. “- Reproduction of
the Central American bushmaster (Lachesis muta stenophrys) and
the Black-headed bushmaster (Lachesis muta melanocephala) for the
first time in captivity.” Bull. Chicago Herp. Society
29(8):165-183.
Kinkaid,
John. 1999. - Your Silent
Fate Awaits You,” ZooNooz, San Diego Zoo & Wild Animal
Park, January 1999.
Bennett,
Albert F. “- Bushmaster,” Discovery
Channel School, original content provided by World
Book Online, (07/14/01)
* Taxonomic classification varies between
references. Classification information used in this fact sheet was
taken from Mammal Species of the World: A Taxonomic And Geographic
Reference, edited by Don E. Wilson and Dee Ann M. Reeder, Second
Edition, 1993.
**Woodland Park Zoo identifies an animal or
plant endangered if it is listed as endangered (in any part of its
range) on the federal list of Endangered and Threatened Species,
or if is listed on Appendix 1 of the Convention on International
Trade in Endangered Species of Wild Fauna and Flora (CITES). |
Classification
and Range
