Boa Constrictors

1. These snakes will take your breath away. Literally.

2. 1. Physical characteristics
Boidae. Average size snake (20 inch. at birth, 8-13 feet as adults). Females generally
larger than males ( 6-8 feet long as adults). Mature boa = 60 pounds.
Colour =depend on their environment. Colours:, brown, grey, cream and red, with dark
cross bands. Helps them to camouflage.
Other Boidaes have obvious heat-sensing pits to find warm-blooded prey. Boas have less
obvious heat-sensing scales.
Aglyphous teeth – fangs don’t carry venom. Teeth similar in size, point towards back of
the mouth.
Constrict and suffocate their prey. 2 equal lungs instead of 1. Pelvic spurs on each side of
the vent (remains of hind legs).

3. 2. Habitat
Tropical forests due to humidity, temperature, natural cover and abundance
of prey. Near the edges of the rainforest. Semi-desert conditions, burrows of
mammals, open savannahs and cultivated fields as well. Accomplished
swimmers, but don't go to the water – terrestrial and arboreal.
Boa constrictors and their subspecies found in:
o Central America: Mexico, Belize, El Salvador, Costa Rica and Panama.
oSouth America: Columbia, Peru, Brazil (mostly in the Amazon rainforest), Bolivia
and Uruguay, among others.
oSome subspecies found on Pacific coasts and many Caribbean islands (Lesser
Antilles, Trinidad, Dominica and St. Lucia, as well as some islands off the coast of
Belize and Honduras).

4. 3. Diet
Cells in their lips that help them to sense heat. Ambush hunters (wait quietly
for prey to pass by).
Size influences types of prey it can swallow. Small animals at daylight and
dusk: monkeys, rats and other rodents, birds, small reptiles (e.g. lizards) and
even wild pigs. Ability to climb trees and live on the ground= increases
hunting range.
Favourite meal = bat, which they will (hunted by hanging from tree branches
near cave mouths). Grab the bat as it tries to enter the cave, then constrict it
to death. Digestion of a large meal = an entire week.

5. 4. Lifecycle
Nocturnal(daytime only to get heat). Most subspecies alone, only associating with other
snakes during mating. Few Dominican subspecies that live in dens together. Females
attract males by emitting a pheromone. Male fertilizes female's eggs internally and
female gives birth to live offspring.
Ovoviviparous – incubate their young internally for 5-8months. Average litter size= 25
(record= +60).
Babies (tiny adults) independent from birth. Childhood: danger of being eaten.
Maturity= three years old.
Moult skin regularly throughout lives to accommodate body growth and to get rid of
parasites. The new skin has already formed beneath the old.
Adults = few natural predators. National Geographic: 20 -30 years in the wild.

6. 5. Risk factors
Deforestation & pollution of rivers. Exotic pet trade.
Predation from other animals (e.g. jaguars). Human hunt to trade their exotic,
fine, ornate snake skin or just to kill them. Some endangered (most have
protected status). Most populations not under threat of immediate extinction.
 
Cold weather (freeze to death because of cold blood).

7. 6. Measures for protection
Respecting their environment: not to cut down so many trees, not to
construct any buildings, etc.
Avoid poaching. Free although they do well in captivity.

8. 7. Interesting facts
Boas have a strong sense of smell and good eyesight.
Boas are said to be the most beautifully colored of all snakes.
The boa constrictor can unhook its jaws wide enough to swallow a whole monkey
headfirst.
In South America, some households keep boa constrictors to control vermin.
 When it's time for boas to mate, a group of males will wrestle in a group with a female
for up to two weeks until one of them wins or until the female chooses one of them.
Boas generally prefer to leave people alone unless they are directly attacked.
Boas only go hunting for food, not for sport.

9. A presentation
made by Andrés
Rodríguez (1º D)
THE ENDTHE END

10. A presentation
made by Andrés
Rodríguez (1º D)
THE ENDTHE END