MEPS 121:27-38 (1995)  -  doi:10.3354/meps121027

Seasonal distribution, relative abundance, biomass production, population consumption, and energy storage in bay anchovy Anchoa mitchilli were estimated from midwater trawl surveys in the upper and mid Chesapeake Bay from April 1990 to October 1991. Abundance and biomass both peaked in late summer and fall before declining significantly in winter, a result of southward migration to lower Bay areas that were not sampled. Production also peaked between summer and fall, a consequence of rapid growth and recruitment of larval and juvenile anchovies. Annual production of young-of-the-year (YOY) anchovy was 856.69 g 100 m^-3, 87.9% of which was produced in the first 3 mo of life. Production by YOY anchovy accounted for nearly all annual production (92.6%) in this short-lived species. Total annual production was estimated to be 233014 t wet wt in upper to mid-Bay regions. The production/biomass (P/B) ratio for YOY anchovy was 8.07 when larval and early juvenile stages were included but only 0.97 without those stages. The estimated translocation of nitrogen biomass from the upper and mid Bay to the lower Bay via anchovy migration was 1027 t N during fall 1990, which is approximately 0.8% of the annual N input to Chesapeake Bay. Estimated population consumption (primarily zooplankton) by bay anchovy ranged from 5.29 to 12.81 g dry wt 100 m^-3 d^-1 in August and from 5.35 to 6.78 g dry wt 100 m^-3 d^-1 in October, suggesting that consumption by larvae and juveniles of this species could significantly impact populations of its plankton prey.

Anchovy . Biomass . Production . Consumption