Qatar Univ. Sci. Bull. (1989), 9: 309-319 BY-CATCH OF COMMERCIAL BOTIOM TRAWL FISHERY FROM QATAR WATERS, ARABIAN GULF By MOHAMED A. IBRAHIM,* KAMAL A. EL-BARY** and JASSIM A. AL-KHAYAT* *Marine Sciences Department, Faculty of Science, University of Qatar Doha, Qatar **Department of Fisheries, Ministry of Industry and Agriculture, State of Qatar. Key words: Marine Fisheries, By-Catch, Bottom Trawl, Arabian Gulf. ABSTRACT The by-catch of the bottom trawl fishery from Qatar water, Arabian Gulf was analysed during the year (1987) on bimopthly basis. It was estimated that 496-635 tons were discarded as by-catch which included a lot of commercialy marketable fish (a check list of them is presented) of these fish 260 tons were longer in length than 15cm, · and 130 ton longer than 20cm. The study recommended inforcing the sorting out (on board the fishing vessels) of fish greater in length than 20cm, exploring the international market for exporting such fish and exploring the possibility of utilizing such fish as processed food. INTRODUCTION Bottom trawl fishery in Qatar is mainly commercial, and is carried out by the fleet of Qatar National Fishing Company (QNFC) which owns three bottom trawlers. In addition, the artisanal sector performs only seasonal bottom trawling for shrimping during the open season for shrimp from july to February. Based on observations and samples of fish discarded; at sea by the tr.awl fishery, at the fishing locations by inshore gillnets and intertidal trap fishery, at the landing points and at the fish market, from offshore drift-net and trap catches; it was estimated that upto 50% of the commercial finfish fishery is being discarded overboard as by-catch. Ibrahim et al, (in press) estimated an amount of tons was discarded as by-catch by QNFC fleet from Qatar waters alone during (1987). Siva and Ibrahim, (1984) repored that, about 58% was discarded during 1980-81 from the same fishery. On the other hand, the artisanal sector in Qatar discards only about 4-5% as by-catch.