Appendix A. Description of the Grand Bay NERR study area.
Ruppia beds occur in ~ 0.5 km2 patches in Middle Bay at depths from 0.5 m to 2.0 m; and SAV density and coverage vary annually with physical conditions. The annual mean surface water temperature of Middle Bay is 22°C and salinity typically ranges from 10 to 30 psu (Mississippi Department of Marine Resources 1998). Nutrients enter into the estuary primarily via surface runoff during rainfall events from adjacent salt-marsh habitat through Bayous Cumbest and Heron. Water column nitrogen concentrations ranged from 0.11 to 0.70 µM in the summer of 2001. Grass shrimp was clearly the most conspicuous and abundant nekton taxon within SAV habitat in the study area. However, shrimp abundance varies seasonally with predation, reproductive cycle and density and with the presence of SAV and emergent grasses. Grass shrimp densities sampled by kicknet ranged from 14 to 196 m2 within surrounding Ruppia habitat during the experimental periods; though actual densities were likely considerably higher.
Mississippi Department of Marine Resources. 1998. Grand Bay National Estuary Research Reserve Final Environmental Impact Statement/Reserve Management Plan.