Monterey, California, is home to insatiably curious and playful harbor seals. Here's what it's like when they're zipping around you while on a dive.

Off the coast of Miami, divers are gearing up for a lionfish derby, organized for the first time by Diver’s Paradise, to help protect Florida’s marine ecosystems.

Few divers would give up the chance to swim with the two largest fish in the sea—whale sharks and basking sharks. Here's where to make it happen.

One travel-weary diver finds respite on a weeklong liveaboard trip. On the agenda: snorkeling with humpback whales in Silver Bank, a protected breeding area.

After sea star wasting disease wiped out more than 90 percent of the ocean's wild sunflower sea star population, divers brave the cold Alaskan waters to find traces of the remaining population.

In this edition of “Ask a Marine Biologist,” Dr. David Shiffman discusses a challenging environment for marine life.

On a late-night dive in Sitka, Alaska, two divers encounter myriad fascinating creatures, including a giant Pacific octopus on the prowl.