This week in Lembongan… The common goatfish is often overlooked by experienced divers as they glide their eyes over the reef and through the coral looking for a crazy small creatures or that next colourful nudibranch. But often while we are working with students and one of these somewhat normal looking fish, starts combing through the rubble looking for food with their barbels, is when the divers start to point.
The family is also sometimes referred to as the red mullets. Goatfishes are characterized by a pair of chin barbels, which contain chemosensory organs and are used to probe the sand or holes in the reef for food. Their bodies are deep and elongated, with forked tails and widely separated dorsal fins. The first dorsal fin has 6-8 spines; the second dorsal has one spine and 8-9 soft rays.
Goatfishes are distributed worldwide in tropical, subtropical and temperate waters. Goatfishes occur in a range of habitats. Most species are associated with the bottom of the littoral, but some species of goatfish can be deep; for example the goatfish Upeneus davidaromi can be found to depths of 500 m. Tropical goatfishes live in association with coral reefs. Some species, such as the freckled goatfish enter estuaries and rivers, although not to any great extent.
Goatfishes are pelagic spawners; they release many buoyant eggs into the water which become part of the plankton. The eggs float freely with the currents until hatching. The larvae drift in oceania waters or in the outer shelf for a period of 4–8 weeks until they metamorphose and develop barbels. Soon thereafter most species take of bottom-feeding life-style, although other species remain in the open water as juveniles or feed on plankton. Juvenile goatfishes often prefer soft bottoms, in seagrass beds to mangroves. They change habitat preference as they develop, coinciding with changes in feeding habits, social behavior and the formation of association with other species. Most species reach reproductive maturity after one or two years.