Emerald Tree Boa
Emerald tree boas rely on sight and infrared “vision” to hunt at night. A snake’s vertical pupils expand to admit as much light as possible so it can detect the movement of small mammals and lizards on the ground. Heat-sensing pits around its mouth produce a precise thermal image of its surroundings, enabling the slender constrictor to accurately intercept its warm-blooded prey in the dark.
Grow into green
At birth, an emerald tree boa can be anything from yellow-orange to brick red. Not emerald. But during its first year, it develops the bright green color, usually broken up by zigzagging white bands that look like dappled sunlight or leaf patterns as the snake rests coiled on a tree branch during the day.
Hunter from above
All boas have a prehensile tail that can grip a branch like a fist. Poised head down in an S-curve from a low branch, an emerald tree boa can lunge up, down, or out to grab its prey, then throw a few coils of its body around it and constrict until the animal suffocates. (Boas are not venomous.) Then it retreats to a branch to swallow its meal whole. These snakes seldom leave their leafy canopy for the ground except to move to another tree, deftly climbing the trunk to safety again. Or at least relative safety: Emerald tree boas are hunted by eagles.