Faced with a rash of shark deaths marked by brain swelling, Canadian and American scientists are trying to solve a marine mystery.

The reptiles, an endangered species, were incapacitated when the water temperature plummeted after a rare winter storm hit the Panhandle last week.

When an upstate New York salmon farm went out of business, nonprofits had days to find a way to catch, refrigerate and clean more than 13,000 fish.

In the Cretaceous period, a shark or another kind of fish found sea lilies less than digestible. What you might expect followed.

The long structures seen in manta rays and their relatives function as an early warning system, rather than a defensive weapon.

Julie Packard discusses highlights of her four decades with the Monterey Bay Aquarium, which she has led since it opened. She’s now stepping back from the role.

A multibillion-dollar expansion helped the canal accommodate king-size cargo ships. It might also be fueling ecological upheaval.

Scientists say the snail darter, whose endangered species status delayed the building of a dam in Tennessee in the 1970s, is a genetic match of a different fish.