Estimation of overall fishing intensity of tuna longline fishery-yellowfin tuna (Thunnus albacares) fishery in the indian ocean as a case study

According to the FAO catch statistics, the total catch of yellowfin tuna (Thunnus albacares) from the Indian Ocean is characterised by decline in the longline fishery and rapid increase in the surface fishery. In the present communication, an attempt has been made to estimate the overall effective fishing intensity of longline fishery for yellowfin tuna by the Japanese longliners during the years 1973–1975. The results on areas and seasons of effective effort expended are presented, along with estimates of tuna availability, effective fishing intensity and the relative gear efficiency.