Photographers capture mutant crayfish, cleaning fish, and synchronized whales in this year's top underwater contests.

PORTLAND, Maine (AP) — Sharks are the most feared predators in the sea, and their survival hinges on fearsome teeth that regrow throughout their lives. But changes in the ocean’s chemistry could put ...

One major division of the kingdom Animalia is Cnidarians (animals built around a central point) and bilaterians (animals with bilateral symmetry), which includes us humans. A study found that the sea ...

ENCINITAS, Calif. — San Diego surfers are never technically alone in the water, but this week a giant ocean sunfish, or mola mola, swam right alongside them before sadly washing ashore at Cardiff ...

This video reveals how a small shrimp uses high speed water jets to hunt and defend itself. By snapping a specialized claw, the animal creates a force strong enough to stun or kill prey instantly.

Of all the schemes that humans have devised to keep sea lions from gorging on the salmon of the Columbia River basin, none has worked for long. Local officials and researchers have chased sea lions ...