Humpback whale's tail - distinctive markings allow identification of individual animals.

Image ID: anim0848, NOAA's Ark (Animals) Collection

Source:
The NOAA Photo Library http://www.photolib.noaa.gov
The National Oceanic & Atmospheric Adminstration (NOAA) http://www.noaa.gov/

The humpback whale (Megaptera novaeangliae) is a species of baleen whale. The humpback has a distinctive body shape, with long pectoral fins and a knobbly head. Found in oceans and seas around the world, humpback whales typically migrate up to 25,000 km each year.