Title: Monitoring and assessment of offshore fishery in Sri Lanka
Abstract
The present study evaluates the trends in offshore fishing activities and reviews the fisheries data collection programme in Sri Lanka from 1994 to 2004. The analysis is based on data from a large pelagic database (PELAGOS) of the National Aquatic Resources Research and Development Agency (NARA). The study reveals a continuous increasing trend of total offshore fishery production in Sri Lanka. Total annual production has decreased from 54,440 to 51,790 tons in the period 1994-1996 while it has increased up to 127,089 tons in 2004. Further total effort and catch per day (CPUE) increased gradually throughout the period considered. The increased landings are largely due to increased tuna catches but continuously increasing billfish landings are also evident. The shark catches show a clear declining trend in the western zone after 1998 and in both the western and southern zones after 2001. Longline and gillnets are the more frequently used gear types of the fleets that were studied. Due to lack of information on effort or catches by gear type, it is difficult to interpret the relative changes in CPUE based on effort or gear type. Length frequency analysis indicates that the dominant length classes of skipjack tuna and yellow fin tuna in the commercial catches lie in the region of 60.0 – 65.0 cm and 50.0 – 55.0 respectively. The analysis performed shows that the current data collection programme is inadequate for assessment purposes. The study attempts to identify some limitations of the sampling programme and comes up with suggestions for further improvements. Introduction of captain's logbooks, expansion of the biological sampling coverage and training for the data collectors are some major points highlighted in this study.