Dispersal dynamics of post-larval blue crabs, Callinectes sapidus, within a wind-driven estuary
We examined how post-larval blue crab (Callinectes sapidus) dispersal occurs within Pamlico Sound, NC, USA, a predominantly wind-driven system. We sampled during multiple 24-h periods over 2 years (2000–01) to relate the spatial distribution of post-larvae in the water column with circulation patterns. A hydrodynamic model of the region was used to recreate dispersal trajectories and to assess potential transport mechanisms and pathways that link near-inlet and across-Sound nursery habitats. Most post-larval blue crabs were collected in surface waters at night, and were consistently distributed within the north-western region of Pamlico Sound. Particle-tracking simulations suggested that dispersal from the inlets to across-Sound nursery habitats only resulted from the combination of tidal and wind-driven currents. Our simulation results further indicated that the northernmost inlet (Oregon Inlet) was the primary supplier of post-larval blue crabs throughout the northern basin of Pamlico Sound, as crabs ingressing through Hatteras Inlet to the south were not retained within our study area. A dispersal pathway connecting Oregon Inlet and across-Sound settlement habitats was evident from field observations. Collectively, our results indicate how multiple forcing agents, coupled with post-larval vertical positioning within the water column, drive estuarine dispersal and connect spatially separated nursery habitats.
Document Type: Research Article
Affiliations: 1: Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695-8208, USA 2: Institute of Marine Sciences, University of North Carolina at Chapel Hill, 3431 Arendell St, Morehead City, NC 28557, USA
Publication date: May 1, 2007