Geoscience Reference
In-Depth Information
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Pit Vipers of the Neotropics
The Neotropical rainforest is home to the larg-
est pit viper in the world, the bushmaster,
which reaches lengths of 6.5-11.7 ft (2.5-3.0
m). Bushmasters inhabit the lowland forests of
Central America and occur throughout the
Amazon forest and the coastal forests of south-
eastern Brazil. One of the most notorious of pit
vipers in the Neotropics is the fer-de-lance. It is
one of 31 lancehead vipers that range from
Central America into the Orinoco Basin of
South America. Fer-de-lances are found in low-
land areas. One snake can typically produce 50
or more offspring in one season. Recent cli-
mate warming in Central America now allows
the fer-de-lance to reproduce twice a year. This
creates a huge population of snakes that have
been leaving the forest and entering planta-
tions in search of food, thereby endangering
the lives of plantation workers and their fami-
lies. Pit vipers are responsible for more human
fatalities than any other snake in the Neo-
tropics. In humans, their venom is fast acting
and causes the rapid destruction of blood cells,
producing an infection that results in severe
necrosis of the bite site and the surrounding
tissue. When antivenom is provided rapidly
and the wound is properly treated, mortality
from a bite is low. In addition to bushmasters
and fer-de-lances, rainforest pit vipers include
forest pit vipers, palm pit vipers (also called
eyelash pit vipers), and hognose pit vipers.
(Rattlesnakes, occurring through North and
Central America, are also pit vipers.)
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tissue or nervous system of their prey. They
mostly eat small mammals and birds. A number
of nonvenomous snakes in the Neotropical rain-
forest have taken on the behavior of pit vipers,
coiling, striking, and even flattening the head to
resemble the distinctive triangular shape of a pit
viper. This type of mimicry attempts to take
advantage of the threat posed by the truly danger-
ous snakes by imitating their appearance and
gestures.
Coral snakes are another type of poisonous
snake found in the Neotropics. Coral snakes are
best recognized by their coloration of red, yellow,
and black bands. Coral snakes have short fangs
that inject venom that directly affects the central
nervous system, producing paralysis and death by
suffocation. Coral snakes are related to the cobras
and mambas of Asia and Africa. They are typi-
cally 2-4 ft (600-1,200 mm) in length and eat
mostly lizards and other snakes. Several less
harmful or nonpoisonous snakes take on the colo-
ration of coral snakes to warn off potential preda-
tors. These look-a-likes are often called false coral
snakes.
The other large group of snakes within the
Neotropical rainforest and other tropical forest
regions are the constrictors (Boidae), the world's
largest snakes. In the Neotropics, these snakes are
called boas; in Africa and Asia, they are called
pythons. These snakes are not poisonous, but
have sharp teeth. Characterized by long wide
heads with pointed snouts and wide bodies, they
capture their prey by attacking and biting it, coil-
ing around it, and tightening their grip until they
suffocate the animal that they swallow whole.
The most common and well-known boa in the
Neotropical rainforest include the beautiful, deep-
green-colored emerald tree boa and the smaller rainbow boas, both excellent tree
climbers. The anaconda, the largest of the Neotropical constrictors, reaches nearly
30 ft (10 m) in length and lives in and along swamps and rivers feeding on large
rodents, peccaries, large birds, tapirs, and even crocodiles. It rivals the rock python
of Africa and reticulated python of Asia in size and weight.
