A Rare Use of a Shark’s Fin? Pectoral Fin Scooping of a Sharksucker from The Flank Area of a Female Blacktip Shark

Sharks react in a variety of ways when sharksuckers attach to their bodies. Here, an unobserved behavior is described in which a blacktip shark, Carcharhinus limbatus, uses a pectoral fin in a scoop-like manner to specifically target the removal of a sharksucker, Echeneis naucrates, in the flank area. This coordinated use of the pectoral fin indicates an established bout in the shark’s repertoire to remove sharksuckers. The anatomical flexibility and coordination of the fin is discussed; likewise, the potential origin and commonality within other species of the same family based on the rise of sharksuckers in the Eocene-Oligocene period. Special emphasis is placed on the value of a single observation of animal behavior in the field.