The green anaconda is the largest snake in South America and one of the
world's big three (the other two are Asian and African pythons). Most
of the herpetologists, or reptile biologists, consider 26 feet to be the
maximum length, but anacondas longer than 15 feet are rare in the wild
If it is not the longest snake species, it is definitely the heaviest.
A 26-footer can weigh 400 pounds. This great bulk is put to use catching
and subduing prey. Anacondas are constrictors. (They are not venemous).
These semi-aquatic snakes lie submerged along stream banks to ambush their
prey. When a caiman, peccary, deer, or large bird comes within striking
distance, an anaconda lunges, bites, and holds the prey while it throws
several coils of its body around the animal. Then the snake constricts,
tightening the coils when the prey inhales, quickly suffocating it. Food
is swallowed whole. Constrictors do not crush their prey - jagged broken
bones would damage their digestive systems.
From Amazon Rising: Seasons of the River. Shedd Aquarium