DESCRIPTION
The Eastern Diamondback Rattlesnake is one of the most feared snakes in the world and rightfully so.
In addition to being the most venomous snake in North America, this ominous species is also the
largest rattlesnake on Earth, averaging between 33 and 72 inches in length (Conant & Collins, 1998).
The characteristic diamonds are dark brown or black in color, and are strongly outlined by a row of
cream-colored or yellowish scales. The ground color of the Eastern Diamondback Rattlesnake can vary
from olive, to brown,to almost black on some individuals. Another indentifiable feature of this species
are the two prominent light lines on the face as well as vertical light lines on the snout
(Conant & Collins, 1998). The Eastern Diamondback possesses a triangular head typical of most vipers,
along with two internasal scutes connected with supraoculars on each side of the head by two large
plates (Stejneger, 1893).
In the field, Crotalus adamanteus is estimated to live an average of ten
years or more and up to 20 years (Studenroth, 2001). The Eastern Diamondback Rattlesnake possesses very
few enemies as an adult, with only deer, pigs, and humans documented as killers of an adult snake. The
name adamanteus is Latin meaning "diamond or lozenge-shaped," referring to the shape of the
dorsal body markings (McCranie, 1980).
Here is a picture of Crotalus adamanteus devouring a cottontail rabbit:
FEEDING AND DIET
The Eastern Diamondback Rattlesnake feasts primarily on rabbits, rodents, and even birds, and has
demonstrated a readiness to capture prey at all times (Kimel, 2002). Like other members of the
Viperidae family, this snake possesses large fangs which it uses to inject large quantities of
venom into its prey. In fact, its fangs are of greater length in proportion to its overall size
than any other poisonous snake in North America (Ditmars, 1933). The bite of this large predator
is easily fatal for humans, often within an hour's time (Ditmars, 1933). However, human fatalities
are rather rare and this snake will usually only bite a human if provoked and provided with no
escape options (Stejneger,1893). Crotalus adamanteus is an ultimate "sit and wait" predator,
using its natural body camouflage to blend in with its surroundings and sit silently until prey comes
within striking distance of its deadly venomous fangs. A single bite with its fangs is easily
enough to kill rodents, rabbits, and other common prey. The venom also contains digestive enzymes
which help break down the prey before the snake even begins to consume it (Bennett, 2002). The
snake will then again wait patiently until the prey has died before devouring it whole.
The
Eastern Diamondback Rattlesnake possesses facial pits, located between the eyes and nostrils, which
allow the snake to detect minute changes in infrared radiation such as the heat produced by living
mammals, at quite some distance (Bennett, 2002). This is why the species is in the pit viper family.
Fortunately for the small mammals and other prey of this magnificent hunter, Crotalus admanteus
does not need to eat very often. In fact, it ceases hunting completely during the winter months and
all told, probably only requires two or three large meals a year, with five or six meals being a
tremendous year (Bennett, 2002).
RANGE
Crotalus adamanteus can be found in the palmetto flatwoods and dry pinelands of South Eastern U.S.A. It
can be found from the coastal lowlands of southeast North Carolina to the extreme east of Louisiana, with
the main concentration located in the state of Florida. This species has also been known to venture into
salt water, making the trip over to the luxurious outlying Keys off the Florida coast (McCranie, 1980). Click here
for a picture of the range of Crotalus adamanteus.
LIFESTYLE AND REPRODUCTION
Originally, the main habitat of the Eastern Diamondback Rattlesnake was the longleaf pine forests of the
Southeast United States. However, with only 2% of those forests still in existence, this snake has been
forced to adapt to man-made habitats such as short-leaf pine forests, vacant lots, and abandoned fields
(Kimel, 2002). As winter approaches in November, Crotalus adamanteus will cease eating and begin
searching for suitable winter housing, such as gopher tortoise and armadillo burrows, stump holes, root
channels, under palmetto thickets, and other underground cavities (Studenroth, 2001). The snake will
leave its burrow temporarily to bask on warm winter days and as the weather gets warmer, this basking
behavior will increase (Kimel, 2002). Finally, once April arrives the animal is ready to begin hunting
again and will remain above ground for the next six or seven months (Bennett, 2002).
In late summer and
early fall (between July and October) the male Eastern Diamondback is at its most mobile, as its searches
for mates (Kimel, 2002). Mating and birthing take place at the same time of year, although females may
not breed every year. These snakes give birth to live young, anywhere between six and twenty at a time,
with an average of about fourteen (Studenroth, 2001). The newborns are born underground and typically
are between twelve and fifteen inches in length with long, fully functional fangs and venom (Kimel, 2002).
This animal demonstrates no observed parental care and the babies leave the birth site as soon as they
shed their first skin (Bennett, 2002). Not much is known about the activities of young rattlesnakes,
although it is believed that they spend much of their first two or three years underground, safe from
hawks and other predators, and close to prey such as rodents (Bennett, 2002).
The home range of
Crotalus adamanteus is rather large, spreading as much as 500 acres for some males, although the
great majority of movement is late in the summer during the search for mates (Studenroth, 2001). These
snakes are primarily terrestrial, rarely climbing into trees and only going underground during the frigid
winter months.
CONSERVATION
The Eastern Diamondback Rattlesnake appears to be declining throughout its range and although it is not
endangered, the species clearly is in trouble (King, 1996). There are numerous causes for this decline,
including loss of habitat. This snake is closely associated with coastal habitat, where beach resort
development takes place, and with the longleaf pine ecosystem, which has been decimated since humans
settled this country (Bennett, 2002). In addition, habitat fragmentation has caused problems, for as the
landscape is broken up by roads, development, and agriculture, the snake is brought into close contact
with humans (Studenroth, 2001). Furthermore, and perhaps most importantly, indiscriminate killing by
humans and "rattlesnake round-ups" are still quite common in much of the Southeast. The hunting of
Eastern Diamondbacks in Georgia is unregulated, with no limit placed on the annual harvest (Kimel, 2002).
The main problem is that a number of people fear these snakes and feel it is their duty to kill any snake,
especially rattlesnakes. Although these "round-ups" are not as numerous as they once were, the
rattlesnake skin trade still exists and takes thousands of Crotalus adamanteus every year
(Studenroth, 2001). Habitat loss, habitat fragmentation, and indiscriminate killing have all contributed
to the decline of this great species.
Despite the fact that the Eastern Diamondback is potentially dangerous, most researchers recognize that
this danger has been greatly exaggerated (Bennett, 2002). In fact, many more people are killed each year
by lightning strikes, bee stings, and domestic dogs, but the perceived public threat is still high
(Studenroth, 2001). In reality, this snake is usually very reluctant to confront humans, and will only
strike in self defense (Bennett, 2002). Public education is key to the conservation of this species
(Studenroth, 2001). Crotalus adamanteus is extremely beneficial to man for it feasts on rats, mice,
rabbits, and other warm blooded rodents and pests (King, 1996). In addition to controlling the rodent
population, the Eastern Diamondback provides food for king snakes, eastern indigo snakes, red-tailed hawks,
great horned owls, and many other species (Kimel, 2002). Moreover, scientists are only beginning to
discover the chemical secrets of this species and other venomous animals (Kimel, 2002). Conservation of
Crotalus adamanteus is vital to the survival of an extensive web of other animals and plants, and
it all starts with public education.
LINKS
Taxonomy and Related Bibliography
Where to find specimens
Peabody Museum, Yale University
Auburn University Museum of Natural History
University of Kansas Natural History Museum
California Academy of Science
Cornell University Museum of Vertebrates