SEASONALITY OF CARIDEAN DECAPOD AND MYSID DISTRIBUTION AND MOVEMENTS WITHIN THE SEVERN ESTUARY AND BRISTOL CHANNEL

Mysids and caridean decapods are a significant proportion of the biomass within the Bristol Channel and Severn Estuary and key members of the marine food web in this estuarine system. Annual patterns of abundance at Hinkley Point Power Station of the mysids Praunus flexuosus, Schistomysis spiritus, Neomysis integer, Mesopodopsis slabberi and Gastrosaccus spinifer and of the carideans Pasiphaea sivado, Palaemon serratus, Pandalus montagui, Crangon crangon and C. allmani are examined. Using population age structures and sex ratios, the patterns of seasonal migration and recruitment are discussed.