THE ANACONDA
The green anaconda (Eunectes murinus). It is a constrictor snake
of the boas family, endemic from the tropical rivers of South America, of all
the snakes this is which has the highest weigh and perhaps the largest known
snake, disputando con la pitón reticulada (Python reticulatus) que habita en
las selvas de Indonesia y Filipinas.
Distribution
The anaconda is endemic from South America; inhabits the
basins of the Orinoco and the Amazon rivers. Also they can be founded in countries
as: Brasil, Bolivia, Colombia, Guyana, Peru, Paraguay, Venezuela and Trinidad
Island.
Description
The anaconda is the biggest snake of America and can exceed
the 8 meters long and weight more than 200 kg. The females are larger than the
males, this is the most marked sexual dimorphism case into the order of these
reptiles are grouped (Squamata).
The anaconda is dark
green in color with oval black spots and ocher on the flanks. The belly is more
clearly, and the end of the tail shows yellow and black designs that are unique
by each one. The body is broad and muscular, adapted to kill their prey by
constriction.
The head is narrow and does not have a distinctive neck. The
nostrils and eyes are in an elevated position, to make breathing and perception
easier during the long periods that the anaconda spend submerged. The eyes of
the anaconda are small and have the typical vertically elliptical pupil of the
poisonous species and the boids, the vision of the anaconda is not very acute.
The olfactory receptors are found on the tongue, like all the snakes.
The snout is covered for six thickened scales, three on each
side, which are the most distinctive trait that separates the genus Eunectes
species from the closely related Boa.
There is a kind of anaconda which the only part of the entire
body is not covered by scales, these ones inhabit in the Caudal region, near
the cloaca zone. In that environs, this anaconda presents spurs which are
remnants of locomotives atrophied limbs.
Habitat and Behavior
The powerful muscles of the anaconda makes it a skillful
swimmer, the green anaconda can travel short distances underwater or on the
surface very quickly, where it is capable of reaching a speed of 6 meters per
second, but on the ground their movements are slow and heavy. The anaconda
choose the camouflage found on the banks of streams as well as the trunks and
beaches to sunbathe or relax. The anaconda used to travel on the rivers , but
prefer the still waters such as ponds or aguajales where most of the time is immersed
to stalk their prey; the position of the nostrils allows it to submerge the most
of the body as a camouflage.
Usually hunt animals that come to drink, it traps them with
jaws and simultaneously wraps itself around its body to suffocate them. With its
immense constrictive forcé, submitted its prey in just over 10 seconds, the
death of his victim is by asphyxia.
The anaconda, like all snakes can not chew food, and instead of,
swallow them integer. Teeth are like needles sharp and directed toward the interior
of the mouth, they serve to retain the prey and allow not escaping. It has four
rows of teeth, one regular and one on the palate used to move the food down her
throat.
When swallowing, the maxilla and mandible, which are fasten
to the skull by ligaments, they manage to separate to accommodate to the size
of the prey.
Feeding
The anaconda is able to consume large preys as; Capybara
(Hydrochoerus hydrochaeris) which is one of his favorite victims and juveniles
unique species as: Brazilian tapir (Tapirus terrestris), Red brocket deer
(Mazama americana) Gray or brown brocket deer (Mazama gouazoubira)
Lizard: Common caiman (Caiman crocodilus), Lizard: Black
Caiman (Melanosuchus niger), Smooth-fronted caiman (Smooth-fronted caiman),
plus other mammals, birds, turtles and other small reptiles.
The snake must alternate to fulfill the process of digestion.
This is because the digestive process requires a lot of energy that the snake
should use to digest the food efficiently, which can last days or weeks, depending
on the size of the pray. The undigestible parts can be excreted or
regurgitated.
Reproduction
According is shown in some field studies conducted to date,
when a female anaconda is sexually available emits a pheromone smell,this is
detected by the male from the area since a distance of 5.5 km.
The pairing of the anaconda occurs between the months of
april and may; Females attract males by an olfactory sign, and they congregate
around them along of several weeks. In the last phase of the courtship, up to a
dozen males curls around the female, fighting for access to the sewer of her,
forming a characteristic ball; They may remain so curled up to 15 days, often
in shallow water, until the bigger and stronger female chooses the winner.
During the mentioned copulation, male spurs stimulate the
caudal region of the female; both sewers get contact and the tails curl while
insemination occurs.
During the actual copulation male spurs stimulate the caudal
region of the female; contact both sewers and tails curl while insemination
occurs.
The anaconda is ovoviviparous, it means that the eggs remain
inside the body of the female until hatching. The gestation lasts 6 months
inside the female. The anaconda can reach to have up to a hundred broods, but
overall the number of the litter oscillates between 20 and 40. Newborns
measures around 70-80 cm long. Because of their small size, often fall as a
prey of other animals, only a few manage to survive till the adulthood.
Conservation
The main threat to their conservation is the destruction of
their habitat and the hunting by those who consider it a threat to domestic
livestock and children, without regard its role in controlling of the rodent
pests.
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Squamata
Suborder: Ophidians
Class: Reptiles
Family: Boidae
Genre: Eunectes
Specie: Eunectes murinus
