Meeting Abstract
P3.12 Jan. 6 Monitoring Larval Abundance and Environmental Conditions to Predict Adult Populations of the Invasive Chinese Mitten Crab, Eriocheir sinensis TSUKIMURA, B.*; RICE, A.; BLUMENSHINE, S.C.; California State University, Fresno; California State University, Fresno; California State University, Fresno BrianT@CSUFresno.edu
The recent invasion of the Chinese mitten crab, Eriocheir sinensis (Crustacea: Decapoda: Grapsoidea), into the Chesapeake Bay has heightened our need to understand the life history characteristics of these aquatic nuisance crustaceans. Since the invasion and expansion into the San Francisco Bay watershed over ten years ago, the mitten crab remains a threat to native species, their habitats, and levee stability (Veldhuizen, 1997; Rudnick et al., 2000). The magnitude of these impacts is related to mitten crab year-class strength, which is strongly affected by environmental parameters. Thus, these environmental factors might be used as predictors for mitten crab population dynamics and year-class strength. We believe adult abundances are regulated at zoea stages. The presence and abundance of zoea was determined using zooplankton trawls and our recently constructed zoea key (Rice & Tsukimura, 2007). Zooplankton samples were obtained from the California Department of Fish and Game (DFG) Neomysis plankton surveys and Clarke-Bumpus samples taken from five sites around San Pablo Bay during April 2003-May 2005. Zoea abundance, water temperature and salinity (USGS), outflow (DWR), and planktivores (DFG) were correlated to find relationships that affect zoea survival. Correlations were seen between adult mitten crab abundances and water temperatures (expressed as % time >11.7�C) experienced by zoea 4 yrs earlier. Stronger patterns emerge when comparing planktivore abundances and freshwater discharge to adult abundances 4 years later. Years with high freshwater discharge are mirrored by strong adult mitten crab abundances 4 years later. Conversely, years with low planktivore abundance are followed, 4 years later, with high adult mitten crab abundance.
