What Lurks Beneath

A reptilian head in a Venezuelan swamp masks the extraordinary size of a tropical serpent

  • Heidi Ridgley
  • Nov 01, 2001

"They say that its eyes shine like miniature lighthouses when it crosses a river." 

SUBMERGED beneath the slow-moving river water except for protruding nostrils and unblinking eyes, a 25-foot-long reptile awaits its prey. Death will most certainly come for any hapless creature that ventures too close--but the end won't happen quickly.

The hunter is the anaconda. A member of the boa family, it will kill its prey not with a venomous bite but slowly by constriction.

Hiding out in or near steamy rivers and swamps in South America east of the Andes from Colombia to Paraguay and also on the island of Trinidad, these semiaquatic serpents are the largest snakes in the world. They can weigh hundreds of pounds and at their thickest point measure some three feet around. Only the reticulated python of Southeast Asia rivals them--but only in length, never in girth.

Photos by Tony Crocetta (Bios / Peter Arnold Inc.)

WRESTLING FOR SCIENCE, researchers in Venezuela prepare to measure what could be a 25-foot anaconda. To help find the submerged giants, they search the muck in bare feet.

Once a snake seizes a victim in its mouth, it coils itself around the body. With each exhalation of the struggling animal, the squeeze tightens. Often death by drowning comes before the prey suffocates, and the anaconda swallows its meal--headfirst and whole. The species' diverse menu includes caiman, peccaries, tapirs, waterfowl, sheep and dogs--basically anything that comes near the shore to drink.

Anacondas rarely attack people, however. But over the years, the big snakes have acquired a reputation as man-eating monsters. Victorian explorers once killed these diurnal giants at every encounter, then measured their already great lengths and embellished the observations. Some reported anacondas as long as 60 feet or described them as having glowing eyes and a foul, hypnotic breath that induced an unshakable stupor in man or beast.

This sort of image has helped make the species more vulnerable to people than people are to them. Thousands are still killed every year out of fear or to sell their skins for use as leather. But their most serious threat today is habitat destruction as swamps are drained and forests cleared.

To protect the anaconda, reserves have been set up in every country within the great snake's range. These pictures by Paris-based photographer Tony Crocetta are from El Frío, a research center in the heart of the Llanos--a vast plain in central Venezuela. Since the early 1990s, biologists there have been studying how best to ensure a future for such a mysterious reptile. Their scientific research invariably yields a massive amount of squirming, hands-on data.

Photos by Tony Crocetta (Bios / Peter Arnold Inc.)

EVEN A FEARSOME spectacled caiman is unable to escape an anaconda's fatal embrace. After slowly digesting this meal, the snake won't feed again for several weeks.

Heidi Ridgley is an associate editor of this magazine.

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