Recruitment of Juvenile Red Drum in North Carolina: Spatiotemporal Patterns of Year-Class Strength and Validation of a Seine Survey

Thursday, September 12, 2013: 11:20 AM
Manning (The Marriott Little Rock)
Nathan M. Bacheler , NOAA Fisheries, Beaufort, NC
Lee M. Paramore , North Carolina Division of Marine Fisheries, Wanchese, NC
Jeffrey A. Buckel , Department of Applied Ecology, North Carolina State University, Morehead City, NC
Frederick S. Scharf , Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC
Twenty-two years of data from a North Carolina Division of Marine Fisheries seining survey were analyzed to assess the validity of the survey, describe spatial and temporal patterns in recruitment of age-0 red drum Sciaenops ocellatus, and evaluate factors that potentially contribute to recruitment variation.  Annual estimates of red drum recruitment were variable over time and showed no long-term trend.  The dome-shaped catch-per-unit-effort (CPUE) pattern of all annual cohorts indicated that the seine survey captured peak abundance levels each year; the spatial coverage of the survey also appeared adequate.  Regional correlations within North Carolina were strongest for areas that were adjacent to one another, and the North Carolina statewide index was not correlated with indices from other states, suggesting that factors controlling recruitment of red drum operate at a scale of ten to hundreds of kilometers.  Variation in loss rates of age-0 red drum appeared to be independent of variation in cohort density.  The CPUE of age-0 red drum was correlated with harvest of age-2 fish 2 years later, suggesting that additional modification of year-class strength after the early juvenile stage is moderate or weak.  Results of this study have improved our understanding of red drum recruitment patterns while simultaneously validating the seine survey.