This gallery focuses on my favorite subject: flukes. Humpback whales lift their tail out of the water as an aid to overcome their buoyancy while propelling themselves on downward dives. This motion creates a cascading waterfall as the whale arches its back to descend from the surface. Each humpback whale fluke has a unique underside pattern that allows conservationists to track individuals. If you look closely, you can see barnacles growing on the outer edges of some tails.