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

Discover how to ethically (and legally) swim with wild dolphins.

Masters of disguise, the leafy sea dragon is one of the trickier ocean critters to spot. Here's why these mythical-looking animals dazzle us—and how to take the perfect photo.

Great whites get all the glory, but bottom-dwelling sharks bring plenty to the table. Here, we're looking at some of our favorite seabed shark species.

The nonprofit Orgcas is making major strides in shark conservation through science, communication, education and local tourism with the help of local fishermen.

Dive into a bit of history in the waters surrounding this remote Antarctic island, the site of famed explorer Sir Ernest Shackleton's harrowing journey.

Climate change is threatening the Maldivian sea turtle population. This is how local resorts are teaming up to protect them.