Models for Clams and Background Prey

Adult clam densities typically range from 0-465 clam/m$^2$ in the middle Patuxent Estuary (McErlean 1964). Most clams ($>73$%) occur in the upper 5 cm of sediment ($< 1.0$ cm in length), however the greatest fraction of biomass is composed of a few relatively large ($> 1.0$ cm length) clams at depths of 10 to 30 cm. In the Chesapeake, Mya arenaria accounted for 75.8% of the standing crop in sand and Macoma for 85.2% in mud.

To simplify model complexity, we only model a single bivalve (Macoma balthica, which we refer to as simply ``clams''). In part, this simplification is forced by the lack of detailed life history information about Macoma mitchelli (but see  Waller (1996)) and other benthic species inhabiting the Neuse. Clams and background prey are modeled spatially at the scale of the finest level triangles used to discretize the estuary (Appendix A.2). This enables hypoxia and crab predation to produce patches of clams and background prey as shown in the movies (See the online appendices). Clam and background prey density are assumed to be homogeneous across each fine-level triangle (Fig. A1).

Subsections

• Clam Growth Dynamics
• Clam Mortality
• Clam Recruitment
• Background Prey