About the World’s Heaviest Snake

By April Sanders

The world’s heaviest snake is known to be the Green Anaconda. Very large and dense, it spends most of its time in the water and can eat animals as large as a deer. Stories abound as to how heavy these snakes can get, but the heaviest Green Anacondas ever weighed all came in at around 550 pounds.

The Facts

  • The Green Anaconda is, pound for pound, the heaviest snake in the world. It is also one of the largest, second only to the Reticulated Python. The Green Anaconda is a member of the Boa family and, like all anacondas, is primarily aquatic. Green Anacondas are usually found in the forests of the Amazon basin and can weigh as much as 550 pounds, or 227 kilograms. Female anacondas give birth to up to three dozen live babies, who are about 2 feet long when born. A group of anacondas are called a bed, or knot. Green Anacondas live for ten or more years in the wild.


  • Green Anacondas live in the tropical waters of the Amazon and Orinoco basins, usually in the sluggish, muddy rivers. The water helps support their massive weight, and they will sometimes wrap themselves around a log for more support. Cumbersome on land, they prefer the water and spend much of their time submerged, with eyes and nose above the water, waiting for prey.


  • Green Anacondas get their name from their skin color, which is olive green overlaid with large black streaks or splotches. Their heads are small, and feature bright orange-yellow stripes on either side. The eyes sit high on the head, as do the nostrils. They can grow to more than 29 feet long, and a foot in diameter, with the females being significantly larger than the males.


  • Green Anacondas are famous for their size, and sometimes that size is greatly exaggerated. Stories abound of sightings of giant anacondas reaching over 100 feet, but the largest measured Green Anaconda measured just over 37 feet. They reach this size by eating small animals such as birds and turtles, as well as larger animals such as wild pigs, deer and rarely, jaguars. They are not venomous, but are constrictors. They wrap their strong bodies around their prey, squeezing until the prey dies. The Green Anaconda will then unhinge its jaw to swallow the prey whole. They can wait weeks or even months between meals.


  • Anacondas have long been portrayed in the media as evil, man-eating snakes. In reality, they will usually retreat when confronted. Green Anacondas will only attack humans as a last, desperate defensive move, such as when cornered or harmed.