The schoolmaster (scientific name: Lutjanus apodus) is a member of the snapper family (Family Lutjanidae) that lives in the Western Atlantic Ocean and the Caribbean Sea.
|Schoolmaster. Source: Florent Charpin www.reefguide.org|
|Juvenile Schoolmaster. Source: USGS|
Kingdom: Animalia (Animals)
Schoolmasters range from 25 to 67 centimeters in length. They have silver bodies, yellow fins and tails, with a long pointed snout, a large mouth, and prominent canines. Juveniles have yellow fins, a series of white and yellow bands along their bodies, and a dark diagonal band running from their snout through each eye.
This species, also known as the dogtooth snapper, is found in the Western Atlantic Ocean from as far north as Massachusetts, USA, southward to northern Brazil, as well as in Bermuda, the Bahamas, the Gulf of Mexico, and the Caribbean Sea.
Schoolmasters live in shallow, clear, warm, coastal waters over coral reefs, often near the shelter of elkhorn corals and gorgonians. Juveniles live over sand bottoms with or without seagrass (Thalassia), and over muddy bottoms of lagoons or mangrove areas. Juvenile schoolmasters sometimes enter brackish waters.
Schoolmasters are generalist carnivores that feed on fishes, shrimps, crabs, worms, gastropods, and cephalopods. At night they leave the reef in search of food.
Schoolmasters characteristically feed nocturnally; correspondingly, since they require rejuvenation at daylight hours, they often form large resting aggregations during the day among the branches of elkhorn coral and gorgonians.
Schoolmasters are pelagic spawners that release both egg and sperm into the water column. After the eggs hatch, the larvae enter the pelagic stage. Eventually, larvae settle in protected nursery areas such as seagrass beds and mangroves.
Studies at the Saba Reef, one of the richest fish assemblages in the Caribbean Basin, have indicated the chief threats to the dogtooth snapper and other reef fishes are overfishing and the residual impacts of the particular chemical dispersant used by the USA in the aftermath of the Deepwater Horizon oil spill; this chemical has high persistence and known toxicity to a gamut of marine fauna. Studies by Burke et al. suggest that concentrations of dispersant and other water pollutants are of particular concern in critical lagoon nurseries; these studies suggest that the toxicity of residual dispersant may be much more significant to reef fishes than the actual petroleum release of an underwater oil spill.
The schoolmaster is not considered to be a species at risk.
References and Further Reading
- J.S.Burke, W.J.Kenworthy and L.L.Wood. 2009. Ontogenetic patterns of concentration indicate lagoon nurseries are essential to common grunts stocks in a Puerto Rican bay. Worldwide Science.org
- Jeffrey T. Williams, Kent E. Carpenter, James L. Van Tassell, Paul Hoetjes, Wes Toller, Peter Etnoyer, Michael Smith. 2010. Biodiversity Assessment of the Fishes of Saba Bank Atoll, Netherlands Antilles. PloS One. 5(5): e10676.
- Encyclopedia of Life. Species curator: C.Michael Hogan. 2011. Lutjanus apodus (Walbaum, 1792)
- P.Humann 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