What a fluke!

Flukes (or tails) of the humpback whales are unique to each individual. While most of the southern humpback whales have a white underside of their fluke, some have black tails; they vary in amounts of black, from a small strip in the center of the tail and peduncle (base of tail), to covering most of their flukes.

These shadings, along with other marks such as spots, lines, notches, scars and bite marks, help scientists identify the flukes easier. The humpback whales in the northern hemisphere have almost exclusively black flukes, making their identification much more challenging.