Marine - Species


Cobia - Click to enlarge photo

SC Species Regulations for Cobia

Saltwater Fishing License required.

Coastal Migratory Species Permit required for charter and headboats.

Limit: 2 per person per day; 33-inch FL minimum.

In state waters may only be taken by rod & reel and gig.

SC Marine Gamefish Tagging

Cobia (Rachycentron canadum)

General Description
Elongated body with dark brown sides and back, 2 sharply defined silver bands on sides. Broad, depressed head, with large, terminal mouth. First dorsal fin consists of 7 – 9 short, isolated spines not connected by a membrane. Long second dorsal fin with 27 – 33 rays. Upper lobe of caudal fin longer than lower lobe.

Average Size
30 inches, 15 pounds;
South Carolina State Record: 92 pounds, 10 ounces (2009);
maximum age: approx. 15 years

Habitat

Adults: Inhabit coastal and continental shelf waters, occasionally enter estuaries. Occur over a variety of live bottoms (sand, mud, rocky) and are often associated with reefs or wrecks, larger marine organisms (rays, sea turtles, sharks), and drifting or stationary objects (buoys, pier pilings, etc.).

Juveniles: Utilize inshore habitats such as estuaries, river mouths, bays, sounds, or inlets, as well as coastal and barrier island or beachfront waters.

Reproductive Cycle

  • Adults mature by 2 – 3 years of age. Approx. size at maturity: males – 24 inches; females – 31 inches.
  • In South Carolina, spawning occurs May – August, most likely in the mouths of bays and sounds. Some spawning also occurs in open ocean waters.
  • Larvae require high salinity waters from the Gulf Stream to nearshore shelf waters. Larval development is rapid and juveniles quickly settle in nearshore habitats.

Foraging Habits

  • Cobia are opportunistic bottom feeders. Adults and large juveniles share a similar diet. In older fish, blue crabs and portunid crabs constitute the major portion of the diet; shrimp (rock, mantis, penaeid) and fish, including elasmobranchs, are also consumed.
  • Larvae and young juveniles consume mostly zooplankton.

Availability/Vulnerability to Harvest

  • Distribution is temperature dependent. An offshore and southward migration coincides with decreasing water temperatures in fall.
  • Present in South Carolina nearshore waters April – October. Peak abundance occurs in late spring; thereafter, larger fish move offshore and are replaced in nearshore waters by younger individuals. Some probably overwinter in deeper water offshore of the state.
  • North of St. Helena Sound, cobia inhabit primarily offshore waters. As a result, fishing pressure in South Carolina is mostly concentrated in Beaufort County.
  • Conservation concerns: degradation of nearshore habitat and water quality; potential for overfishing; lack of knowledge of spawning sites and larval and juvenile habitats in South Carolina waters.

Abundance of Species

Graph

Graphs of abundance show relative annual abundance in South Carolina waters based on surveys conducted by the SC Department of Natural Resources.

Abundance is presented relative to the average of the 10 most recent years. Unlike graphs of the recreational and commercial fisheries catch, the abundance graphs use survey data that have been standardized to allow direct comparison among years.

The horizontal dotted lines above or below the "10 year average" represent one "standard deviation" unit, which is a measure of how variable the annual data are around the 10-year average. In general, the area between one standard deviation above the mean and one standard deviation below the average includes approximately 68% of the values. Approximately 95% percent of observations in the data set are found within two standard deviations of the average.

Fishery Status

Cobia Recreational Fishery Graph - Select image to view larger graphRecreational landings for cobia remained relatively stable through the 1980's and 1990's and then increased dramatically in the early 2000's. After 2007, total landings returned to similar levels as the 1981-2002 time period. Most years (except for 2003-2007) were below the ten year average total catch due to the high catches that occurred during 2003-2007.

Commercial landings were cyclical with peaks in catches occurring approximately every ten years from the 1980's to the early 2000's. Commercial landings have decrasted since 2003 with a 10 year average of approximately 4,200 lbs per year. The highest reported commercial landings for cobia occurred back in the early 1980's. More Information.

Literature Cited

Fischer W. 1978. FAO identification sheets for fisheries purposes: western central Atlantic (fishing area 31) volume 1 – 7. Food and Agriculture Organization of the United Nations, Rome.

Hammond DL. 2001. Status of the South Carolina fisheries for cobia. Marine Resources Division, South Carolina Department of Natural Resource, Charleston, SC. 22 pp.

Hammond DL. 2005. Cobia. In: Comprehensive Wildlife Conservation Strategy. South Carolina Department of Natural Resources, Columbia, S.C. Available: https://www.dnr.sc.gov/cwcs/pdf/Cobia.pdf. Accessed: September, 2009.

Moore CJ, M Barkley. 2005. South Carolina’s guide to saltwater fishes. South Carolina Department of Natural Resources, Special Publication. Columbia, SC. 132 pp.

Moore CJ. 1996. A field guide to the identification of marine species regulated in South Carolina coastal waters. Office of Fisheries Management, Marine Resources Division, South Carolina Wildlife and Marine Resources Department, Charleston, SC. 105 pp.

Shaffer RV, Nakamura EL. 1989. Synopsis of biological data on the cobia Rachycentron canadum (Pisces: Rachycentridae). NOAA Technical Report NMFS 82, National Marine Fisheries Service, Washington DC. 21 pp.

Smith JW. 1995. Life history of cobia, Rachycentron canadum, (Osteichthyes: Rachycentridae), in North Carolina waters. Brimleyana 23: 1-23.