LONGLINE SELECTIVITY AND FISHING PRESSURE ON THE FISHERY OF LETHRINUS ELONGATUS OFF THOOTHUKUDI COAST

A study on the long line hook selectivity and fishing pressure on Lethrinus elongatus owing to the use of four different sizes of hook revealed notable selectivity of different size hooks and heavy fishing pressure on juveniles due to the use of hook No10&11.The length frequency distribution followed normal distribution, however with a skew . The general shift of peaks towards the higher length group as increase of hook size indicated clear cut selectivity of hooks. The peak fishing season was found to be from January to April although year round fishery could be observed. The CPUE was maximum to the tune of 23.8kg/ boat day during the month of March while the annual CPUE being 11.78kg/boat day. Considering the hooking rate and length at first maturity, the optimum hook size for the commercial exploitation of L. elongatus was arrived as hook No 9. The study suggested to improve the design of the long line units of Thoothukudi coast incorporating basic components such as sekiyama, swivel and snood wire in the branch lines, besides introducing advanced type of hooks and line haulers