Kent L. Nelson

Assessment of Striped Bass Spawning Stock in Roanoke River, North Carolina

A total of 4,920 striped bass (Morone saxatilis) were collected from Roanoke River near Weldon, North Carolina, by electrofishing during the spring of 1991 and 1992. Study objectives were to determine sex ratio and age composition of the Albemarle Sound/Roanoke River striped bass spawning stock. Differences in catch per unit effort (CPUE) between years, among year classes, and between sexes were analyzed. Male striped bass represented 83% and 87% of the sample over the 2 years. Nearly all male (99%) and female (91%) striped bass captured were Ages 2 through 4. Ninety-six percent of the...


Increasing the Effectiveness of Electrofishing Boats in Low Conductivity Waters

The anode and cathode arrangements on an electrofishing boat using pulsed D.C. output were manipulated to increase the effective area of the electric field. Voltage gradient (volts/cm) measurements were taken at various distances and depths at 90 and 180 degrees in relation to the long axis of the electrofishing boat. The objective of the study was to improve the efficiency of the electrofisher in low conductivity waters. The maximum distance and depth of field increased an average of 71% and 72%, respectively, for the 2 sample sites when comparing the initial configuration (IS-cm anode...


Evaluation of the Relative Selectivity of Sampling Gear on Ictalurid Populations in the Neuse River

Five techniques (electrofishers, hoop nets, gill nets, wire traps, and trotlines) were used to sample ictalurids in the Neuse River above New Bern, North Carolina, between July 1984 and May 1985. Hoop nets were the most effective of the sampling gears tested. They collected white catfish (lctalurus catus), channel catfish (l. punctatus), blue catfish (l. furcatus), yellow bullhead (l. natalis), and margined madtom (Noturus insignis) and accounted for 76% of the total number of fish caught. Electrofishing (low voltage) captured white catfish, yellow bullhead, and margined madtom, which...


Effects of Excavation and Snagging on the Fish Populations of a Coastal Stream in North Carolina

Island Creek, a tributary of the Northeast Cape Fear River in Duplin County, North Carolina, was modified through excavation and snagging during 1977 and 1978. To evaluate the effects on resident fish populations, rotenone samples were taken before alteration in 1977 and after the project in 1981 and 1982. Mean standing crop of fish increased from 27.5 to 38.3 kg/ha after the project and total number of fish captured increased from 424 to 1,058. Significantly greater (P < 0.05) centrarchid and total game fish biomass were found after the project. No statistically significant differences...