The hawkfish are a group of predatory saltwater fish that have a wide range throughout the Indian and Pacific oceans. Named for their unique method of hunting, these colorful and active fish are a favorite for saltwater aquariums. There are more than 30 species of hawkfish, all members of the family Cirrhitidae and order Perciformes, but divided into different genera.
Found mainly around coral reefs, these fish have a native range of some of the tropical areas of the Atlantic Ocean and throughout the Pacific and Indian oceans. These shallow-water dwellers are usually found in areas of coral reefs where they can perch on an outcropping and look down on prey that swims below them. In the hunting method that gives them their name, hawkfish can dive and strike their prey quickly and accurately.
These ocean fish thrive on smaller fish, plankton, and even small crustaceans. This carnivorous diet makes matching them with tank mates in captivity a challenge, as they will hunt and devour many saltwater fish and crabs that may be in their vicinity. Hardy fish, they can quickly adapt to a tank environment but can become extremely territorial if the landscape of the tank is not changed occasionally. In the ocean, a single male will often be found sharing a space with two to seven females; if the male dies, one of the females from the group will change her gender and take over in the male role. This trait is called protogynous synchronous hermaphroditism.
There are many shapes and colors of hawkfish, although most of the species used in home aquariums are less than 6 inches (15 cm) in length. Ocean-dwellers can reach up to 39 inches (1 m), and males are typically slightly larger than females. Species can be spotted like the pixy, striped like the falco, or nearly solid like the arc eye. Some have a shape distinctively different from other hawkfish; the longnose is named for its most noticeable feature and the one that sets it apart from other hawkfish.
In spite of their predatory nature, with a few precautions hawkfish can be among the easiest of marine fish to keep in a saltwater tank. A tank of at least 20 gallons (75 liters) is recommended as the minimum size to keep hawkfish content. As they are naturally tropical ocean-dwellers, temperatures between 75 and 80 °F (23 to 26 °C) are appropriate.