Abundance estimation of sergestid shrimp Sergia lucens in Suruga Bay

Abstract

Abundances of 1998-2001 year classes of sergestid shrimp in Suruga Bay were estimated by virtual population analysis using the data of length frequency and catches. The numbers (biomass) of recruits were estimated to be 97.3 × 108 indiv. (2,475 t), 103.0 × 108 indiv. (2,195 t), 82.5 × 108 indiv. (2,288 t), and 71.9 × 108 indiv. (1,856 t) in 1998, 1999, 2000, and 2001, respectively. The estimated numbers of recruits were about 1/20-1/4 of the levels of 1961-1965 year classes.