The Influence of Spat Density on Mud Crab Predation

Many predators of spat exist in the Chesapeake Bay, but the direct effects of predation on spat survival in Maryland are not well understood.  In 2009 Rebecca Kulp, an undergraduate honor student in the lab, identified the flat mud crab (Eurypanopeus depressus) as a main predator of spat in a lab-based experiment.

Undergraduate student Taylor Davis conducted a lab experiment in 2012 to examine the impacts of spat density on E. depressus predation.  Taylor investigated the percent of spat eaten by individual mud crabs when presented with various densities of spat (10, 30, and 60 spat/ 2.5 gallon aquarium treatment).  We hope to continue this line of study by testing mud crab predation at a wider range of spat densities and strengthening the power of the experiment by increasing the number of replicates of each density.

Figure 1. Experimental setup for spat density and mud crab predation experiment. Taylor investigated predation of spat when crabs were presented with three density treatments of spat.