Introduction

The spotfin butterflyfish (scientific name: Chaetodon ocellatus) is a member of the butterflyfish family (Family Chaetodontidae) that lives on coral reefs in the Western Atlantic Ocean and the  Caribbean Sea .

Physical Description

Spotfin butterflyfish range in length from 7.5 to 20.0 centimeters in length.  Their thin, oval bodies are white and they have bright yellow fins (except the pectoral fins).  They have black bar on their head that runs through their eye and a black dot on the rear edge of their dorsal fin.

Distribution

Distribution map for the Spotfin butterflyfish. Source: Florida Museum of Natural History

This species found in the Western Atlantic from as far as 43.35° to Brazil, as well as in the Bahamas, the  Gulf of Mexico , and the Caribbean Sea.  Larvae may occasionally be swept northwards by the current so spotfin butterflyfish juveniles have been found as far north as Nova Scotia, Canada.

Habitat

They live on  coral reefs  at depths ranging from zero to 30  meters . 

Feeding Behavior

Spotfin butterflyfish are generalist  carnivores  that feed on tubeworms, hydroids, and small crustaceans. They are diurnal foragers who rely on their eye sight to detect their prey.

Behavior

At night they change colors, forming dusky bands in an attempt to hide from nocturnal predators.

Reproduction

Spotfin butterflyfish larval form. Florida Museum of Natural History Little is known about the mating behavior of spotfin butterflyfish, beyond that they are thought to breed in pairs.  They spwan in the water column, and once their eggs hatch, about a day after fertilization,  they larvae enter the planktonic stage. They larvae, known as tholichthys,are surrounded by a series of bony plates.  When the larvae reach about 20 millimeters in size they settle onto the reef..  The larvae typcially settle at night to reduce the risk and predation and then rapidly transform into a juvenile.   Juveniles live in sea grass beds, mangroves, or around isolated coral heads.  They reach maturity in about one year.

Conservation Status

The spotfin butterflyfish is not deemed to be a species at risk.

References and Further Reading

• Encyclopedia of Life. 2011. Chaetodon ocellatus Bloch, 1787
• Casey Patton and Cathy Bester. Spotfin Butterflyfish
• P.Humann and N.Deloach. Butterflyfish. FishID website
• P.Humann P. and N.Deloach (Editors), 1994. Reef Fish Identification: Florida, Caribbean, Bahamas. New World Publications, Inc. Jacksonville, FL. ISBN: 1878348078
• N.Deloach. 1999. Reef Fish Behavior, Florida, Caribbean, Bahamas. New World Publications, Inc. Jacksonville, FL. ISBN: 1878348280