Pilot fish usually gather around sharks (also rays and sea turtles). They eat parasites on their host, and small pieces of food that their host does not eat (leftovers). When pilot fish are young, they gather around jellyfish and drifting seaweeds.
Pilot fish follow sharks because other animals which might eat them will not come near a shark. In return, sharks do not eat pilot fish because pilot fish eat their parasites. This is called a "mutualist" relationship. Small pilot fish are often seen swimming into the mouth of a shark to eat small pieces of food from the shark's teeth. Sailors even said that sharks and pilot fish act like close friends. When a ship would capture the shark the pilot fish followed, some people reported that the pilot fish would follow the ship for up to six weeks.
The pilot fish is of a dark blue to blackish-silver colour, and are slightly lighter in colour underneath. They have between 5 and 7 dark stripes going from top to bottom. When the fish is excited, these stripes disappear, and three large blue patches appear on its back. The pilot fish is usually about 30 cm long, but sometimes they can be as big as 70cm.
The pilot fish will not hurt people, and they are said to be good to eat. They are very difficult to catch, though.
- "ITIS Standard Report Page: Naucrates ductor". ITIS. Retrieved 2007-09-26.
- Randall, John; Allen, Gerald and Steen, Roger (1997). Fishes of the Great Barrier Reef and Coral Sea. University of Hawaii Press. p. 164. ISBN 0824818954.CS1 maint: multiple names: authors list (link)
- Eschmeyer, William N.; Herald, Earl Stannard (1999). A Field Guide to Pacific Coast Fishes. Houghton Mifflin Books. pp. 208–209. ISBN 0395268737.
- Stafford-Deitsch, Jeremy (2000). Sharks of Florida, the Bahamas, the Caribbean and the Gulf of Mexico. Trident Press. p. 32. ISBN 1900724456.
- "Naucrates ductor, Pilotfish". FishBase. Retrieved 2007-09-26.
- NOAA Library Image: http://www.photolib.noaa.gov/historic/nmfs/figb0368.htm
- Naucrates ductor at FishBase