On September 16, 2010, I had the opportunity to accompany researchers Bill Roumillat and Justin Hart of the South Carolina Department of Natural Resources on an electro-fishing survey trip on the Combahee River. Data collected throughout the year by the SC DNR Inshore Fisheries Section / ACE Basin National Estuarine Reserve Research (NERR) is accumulated for fishery research and management. I was absolutely amazed at the diversity of fishes netted as well as the dedication of the crew. We launched in the morning at the ramp adjacent to the Highway 17 Harriet Tubman Bridge on a falling tide and traveled upstream to where the salinity was low enough to allow the electro-shocking equipment to operate. NERR data is collected from determined data points in the river channel during mid-tide cycles while the water is below the grass marsh.
The SCDNR operates its specialized research electro-fishing boat by Smith-Root for these surveys.
The boat produces an electric field between the electrode arrays extended off the bow and the boat’s bow. Some fish are attracted to the electric field and can be observed swimming helplessly toward it. Others boil up when they encounter the field.
Previously mapped data points are used to locate 15-minute interval shocking passes with two crewmen on the bow of the boat netting stunned fish which are transferred to the holding tank for speciation, data collection and release. Variables of water temperature, salinity, dissolved oxygen, and turbidity are recorded along with species netted, length. Additional information for red drum, largemouth bass, and striped bass are also taken. Fin clip samples are taken for red drum and striped bass and these fish are also tagged before release.
A few of the more striking aspects to this trip were:
While the weather for my trip was very pleasant, the SC DNR Inshore Fishery crews routinely go on these electro-fishing survey trips throughout every month of the year, rain or shine. I was fortunate in the respect that the weather on this day was as fine as it could be in September.
The crew’s dedication to accurate data and their dedication as well as their commitment to utilize this data in an effort to understand and efficiently plan and manage the ACE Basin fishery could not be overstated.
A partial list of species netted: Mullet (by far the most numerous specie netted), Gizzard Shad, Red Drum, Striped Bass, Spot, Bowfin, Blue Catfish, Channel Catfish, White Catfish, Largemouth Bass, Bluegill, Red Ear Bream, Red Breast Bream, American Eel, Sheepshead, Carp and Flounder. Additional observations were made on the presence or absence of parasites on the American Eel and Flounder.
