The spotted seatrout is not a member of the trout family (Salmonidae), but of the drum family (Sciaenidae) which includes common inhabitants of South Carolina waters such as Atlantic croaker, red drum, and spot. Two other species of seatrouts inhabit state waters: weakfish, Cynoscion regalis, and sand seatrout, Cynoscion nothus. All seatrouts are elongate with a protruding lower jaw. Their mouths are rather large with sharp teeth. Spotted trout are gray with bluish reflections above and silvery below. The fins are yellowish green, except for the first dorsal fin which is dusky. They can be distinguished from other seatrouts by numerous black spots on their upper side, second dorsal fin, and caudal fin. Maximum adult size in this species is 90 cm (35 in).
Habitat and Biology
Spotted seatrout are found along the eastern coast of the United States from Chesapeake Bay to the southern tip of Florida and along the Gulf coast to the northeast Mexican coast. Spotted seatrout are estuarine dependent, and with the exception of forays into the nearshore waters during the warmer months of the year, they spend their whole lives inside estuaries. Male spotted seatrout mature at a much smaller size than females. Regardless of the month in which a male spotted seatrout was spawned the previous year, it will become mature and actively spawn the following May (as small as 19 cm or 7.5 inches). Female spotted seatrout do not become mature until they attain a size of about 25.4 cm (10 in) in length, approximately one year after spawning. Females spawned near the end of the spawning season of the previous year will not mature until the following spawning season.
Seatrout spawn at specific locations in South Carolina's estuaries from May through early September. Typically, these sites have swiftly moving currents with obstructions on the bottom and are either in high salinity areas or are near the inlets. During the spawning season, mature males produce a "drumming" sound by contracting muscles near the swim bladder. All fish belonging to this family produce these noises (hence the common name of "drums"). Females are attracted by the drumming to areas where large numbers of males are gathered. Spawning occurs in such gatherings, or aggregations, near dusk. Larvae are transported by tidal currents to the shallow estuarine habitat such as dendritic tidal creeks, muds flats, oyster bars, and intertidal marshes. In these tidal creeks, juvenile spotted seatrout feed on crustaceans, mainly grass shrimp, and small fishes. They remain in this habitat until reaching a length of about 6 inches after ,which they move to larger, deeper estuarine creeks. In the coldest months of the year (December through early March), young-of-year spotted seatrout move to the deeper holes in the smaller creeks and on the edges of the main channels. As the waters warm in the spring, they form schools of like-sized individuals and move throughout the estuary feeding on small fishes and shrimp.
Spotted seatrout approximately 33 cm (13 in) feed on small fishes and shrimps found in shallow waters near flooded marsh grass, and as they grow, fish become the preferred prey. Males grow more slowly than females and reach a smaller maximum size. The oldest spotted seatrout aged in South Carolina was 8 years old.
The spotted seatrout is one of the most popular sport fish along the eastern coast of the United States and Gulf of Mexico. It ranks second by weight among recreational saltwater anglers mainly in the southeastern United States. In South Carolina, the species was officially declared a gamefish on July 1, 1986. Trout can only be harvested by means of hook and line or by gig in South Carolina waters. Hook and line harvest is allowed throughout the year, whereas use of gigs is permitted only from March through November. Currently, there is a size limit of 33 cm (13 in) and a bag limit of 10 fish per angler per day.
The Marine Division of the South Carolina Department of Natural Resources, in conjunction with the National Marine Fisheries Service, recently reported that the total recreational catch for spotted seatrout averaged 266,000 individuals per year over an 11-year period. The population of spotted seatrout in state waters is declining, albeit slowly, due to increased fishing pressure. However, changes in the way the spotted seatrout resource is managed in South Carolina and other Atlantic states can ensure a stable future for seatrout populations.
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Murdy, E.O., R.S. Birdsong, and J.A. Musick. 1997. Fishes of the Chesapeake Bay. Smithsonian Institution Press, Washington, DC.
Wenner, C. 1998. Personal communication. South Carolina Department of Natural Resources, Charleston, SC.
Wenner, C.A. and J. Archambault. 1996. Spotted seatrout: Natural history and fishing techniques in South Carolina. South Carolina Department of Natural Resources, Marine Resources Research Institute Educational Report 18.