Spring 2003 crab population monitoring: mid-marsh and creekbank abundance based on crab hole counts at GCE marsh, monitoring sites 1-10

This data set is the Spring 2003 estimate of crab densities at the GCE-LTER marsh sites used for population monitoring. Crab abundance was determined by counting the number of crab holes within a 625 cm^2 quadrat and converting the counts to number per square meter. Counts were made in the mid-marsh and creekbank zones (n = 4 per zone) at all sites. This method does not differentiate which species made a particular hole and therefore only estimates total crab abundance. Plugged holes were excluded from the counts. Mean density across all sites and zones was 264 m^-2 (+/- 215 s.d.).