Empirical NWACS Analyses

We conducted a number of analyses of individual species to document the degree of connectivity they demonstrated among NWACS regions. The methodology for all analyses were similar. First we extracted fishery-independent, and fishery dependent data from our NWACS database. Where necessary, we then conducted simple population assessments (catch-survey models) to develop estimates of population abundance. We then subjected either the fishery independent data, or the derived population estimates to statistical analysis. Sample analyses include:

Adult-mediated Population Connectivity

In this conceptual paper, we suggest that the traditional focus on early life stages of fish and marine invertebrate as agents of connectivity misses the fact that many marine fish undergo extensive migrations to place their offspring in the "correct environment."

Blue crab

These analyses used population estimates derived from catch-survey models for fished stocks from Florida to New York. Results indicated a clear difference between populations north and south of Cape Hatteras, NC. AMO

Atlantic menhaden

These analyses used fishery-independent estimates of recruitment, because spatially-explicit fishery-independent estimates of adult menhaden are lacking. We used a similar approach to that for blue crab. Again, the importance of a breakpoint for the synchrony of populations north and south of Caper Hatteras, NC was identified.

Last revised: 1/18/2016