Kirk Rundle, a fisheries biologist with the N.C. Wildlife Resource Commission, said Shearon Harris Lake is usually sampled every other fall for crappie, with the last sample taken in November 2014.
Biologists typically set out 12 trap nets overnight for three or four nights, checking them every day. After one or two nights, the nets are moved to new locations.
The November 2014 sample yielded 568 black crappie and no white crappie. Catch rates were good, with 15.8 fish per net per night compared to average Piedmont reservoir catch rates of four to 18 fish. Growth rates were also good, with the average length of an age-2 fish at about 8 inches.
The relative weight was good at Harris, with an average of 93. The average Piedmont crappie ranges from 85 to 95. A value of 100 means that the lake has a lot of fat crappie and could support more. If relative weights are consistently well above-average, that suggests numbers are down, and overharvest may be occurring.
In the Harris sample, 92 percent of crappies were longer than 8 inches, and 49 percent were longer than 10 inches. About 10 percent of the fish sampled weighed more than a pound. The sample also contained fish that were up to 8 years old.