Fishery forecast using OCM chlorophyll concentration and AVHRR SST: validation results off Gujarat coast, India

Abstract

Satellite sensor data analysis, generation of fishery forecast, validation procedure, feedback analysis and results of validation experiments are discussed in this Letter. Indian Remote Sensing Satellite (IRS-P4) Ocean Colour Monitor (OCM) derived chlorophyll concentration and National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (NOAA-AVHRR) derived sea surface temperature (SST) images were integrated to generate a fishery forecast. The matching chlorophyll and SST features were selected to suggest potential fishing zones (PFZs). Actual fishing using trawlers in the suggested PFZs was carried out to validate the fishery forecast. The feedback in terms of CPUE (catch per unit effort) was analysed to evaluate the technique. The CPUEs were categorized based on mean (µ) and standard deviation (SD). The categorized catch points were plotted on images. High fish catch points were found in the vicinity of matching features. About 80 per cent of observations in 50–100 m depth zone and 68 per cent of observations in 30–50 m depth zone were found positive. At some locations an abrupt increase in CPUE in PFZs was observed.