Spawning migration of telemetered striped bass in the Roanoke River, North Carolina
bass, migration, spawning, striped bass, behavior, regulations, survey, telemetry
Journal or Book Title
Transactions of the American Fisheries Society
The spring spawning migration is a key period for effective management ofanadromous populations of striped bass (Morone saxatilis). Information on migratory behavior isneeded in order to develop appropriate harvest regulations and to conduct effective surveys whilefish are on the spawning grounds. We used ultrasonic telemetry to estimate the timing andduration of the upriver spawning migration for the Roanoke River, North Carolina, population andto evaluate whether a short-term fluctuation in temperature or flow would alter the distribution oftelemetered fish on the spawning grounds. Seventy-eight fish implanted with transmitters werereleased during 1993 and 1994. Twenty-nine telemetered fish migrated upriver in 1994, and 14telemetered fish entered the river in 1995. Migration of telemetered fish began in mid- to late April when water temperatures in the lower river reached 17–18 °C. Males began their spawningmigration significantly earlier than females in 1994; the difference was not significant in 1995. The165-km upriver migration took about a week, as did the downriver migration after the spawningseason. In 1994 and 1995 respectively, males remained on the spawning grounds for averages of22 and 21 d, females for 8 and 11 d. Because of shorter residency times only about half thetelemetered females were on the spawning grounds at any one time during the peak of thespawning season. Striped bass remained on the spawning grounds during a short-termtemperature decrease of about 4 °C (over 5 d) and an increase in flow from about 190 to 390m3/s (over 1 d).