Are snakes and eels related?

The yellow-lipped sea snake returns to land to mate and lay eggs. (Photo by Jacob Rudolph)

The yellow-lipped sea snake returns to land to mate and lay eggs. (Photo by Jacob Rudolph)

May 2006

No. Snakes are reptiles and eels are fish. Both are vertebrates and belong to the animal kingdom, but that’s where similarities end.

Sea snakes do exist, however, and some land snakes, such as the cottonmouth and several species of water snakes, are semiaquatic and well adapted to life in fresh water.

Sea snakes are fascinating animals. Of 70 known species of sea snakes all are true snakes with lungs. Most can remain submerged for 90 minutes or more, but typically surface several times an hour. They are relatives of cobras, highly venomous, and found in great numbers in the tropical waters of the Indian and Pacific Oceans. The venom is an extremely potent cocktail of toxins used for subduing prey, and their fangs are small. Fortunately, fatal bites to humans are rare.

Most sea snakes never leave the water. They bear live young in the sea, and only sea kraits, a type of sea snake, venture onto land to lay eggs. Sea snake diets consist primarily of fish, but some, such as the yellow-lipped sea snake, dine exclusively on eels.