Grass shrimp (Palaemonetes spp.) are among the most abundant macrocrustaceans in estuaries of the US Atlantic and the northern Gulf of Mexico. Although grass shrimp is a significant link in the food web of the Maryland Coastal Bays (MCBs), information is lacking on its population dynamics. The objectives of this study were to evaluate the temporal and spatial variation of grass shrimp abundance in the MCBs using data collected from 1994 to 2017. We hypothesized that grass shrimp abundance is higher in the northern bays than in the southern bays due to higher densities of macroalgae and phytoplankton in the northern bays. Results showed a higher catch-per-unit-effort (CPUE) of grass shrimp in the northern than southern bays for each month (p < 0.05) from April to October. Grass shrimp CPUE was highest in the spring and lowest in the summer months when the abundance of juvenile fishes is typically at its peak. The CPUE of the shrimp also varied among years, although no increasing or decreasing trend was observed. The lowest mean CPUE of the shrimp was noted in 1996 (40+1.05SE) and the highest occurred in 2002 (608+12SE). The temporal and spatial variations in CPUE of grass shrimp likely influence their trophic role as major prey for several fish species, predators of meiofauna and small infaunal invertebrates, and as grazers on epiphytic algae on saltmarsh grasses in MCBs.

Primary Presenter: Jocelyn Lucente, University of Maryland Eastern Shore (jl572@humboldt.edu)

Authors:

Jocelyn Lucente,   (jl572@humboldt.edu)

Ashley Silver, University of Maryland Eastern shore  (acsilver@umes.edu)

Paulinus Chigbu, University of Maryland Eastern Shore  (pchigbu@umes.edu)