Marine - Species - Southern Flounder

Abundance of Species

Southern Flounder Abundance in SC 1990-210

Southern flounder numbers have declined in the SCDNR trammel net survey over the last 20 years. A separate analysis of SEAMAP data suggests a similar decline in flounder numbers, which is most pronounced around Charleston Harbor.

Additional Graph Information

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.