Relationship Between Early Life Stages of Louisiana White Shrimp and Subsequent Landings

摘要

Louisiana white shrimp Litopenaeus setiferus landings display substantial intra-annual and interannual variability. This variability reflects differential impacts of a variety of environmental factors that influence growth, mortality, and subsequent survival in a given year. For purposes of examining factors contributing to this intra-annual and inter-annual variability, we developed a recursive three-equation model in which different life stages for Louisiana white shrimp are predicted on a monthlybasis, based on environmental parameters such as temperature, river discharge, cumulative wetland loss, and lagged previous stage counts. Results indicated a positive relationship between abundance of shrimp at its early life stages in relation to temperature and salinity. Wetland loss and higher river discharge seem to lessen abundance, while biological factors, such as high number of juvenile shrimp at its early life stage, predict late juveniles well and similar relationship exits between late juveniles and the catch per unit effort.