Follow a baby humpback whale as she travels from her birthplace in Hawaii, to feeding grounds off Alaska’s coast. Watch the full episode now.

A fight breaks out among a group of humpback bulls that are vying to mate with a female.

Humpback whales form teams for cooperative feeding -- and create quite a spectacle in the process.

Steller's sea lions are rapidly disappearing from Alaska's waters, and no one knows why. A broad combination of factors could be responsible.

Spinners congregate in superpods of hundreds, coordinating a hunt - and spinning! Scientists do not know for certain why they spin.

After the Nicaraguan government finds out that two dolphins have been captured for a "swim-with" program at a resort hotel, rescuers are dispatched to track them down.

Filmmaker Hardy Jones used his camera as a tool for conservation, filming dramatic dolphin hunts and documenting the effects of chemical pollution on dolphins and orcas.

For decades, Hardy Jones has been working to expose and stop the trade in dolphins used for food and entertainment. In some cases, Jones's footage has helped stop dolphin captures.

Dolphins use sound to detect the size, shape, and speed of objects hundreds of yards away. The dolphin's natural sonar, called echolocation, is incredibly precise

Manatees are marine mammals, like dolphins and whales. But they don't share a dolphin's sleek shape.