Study of Fishing Gears ,Crafts And Techniques of Migratory fishermen In the Cochin Back Waters

Abstract- A study of the crafts and gears used by the migratory fishermen in Cochin backwaters, Kerala was conducted for a period of one year from June 2016 to May 2017.Based on a preliminary survey the main areas were migratory fishermen are based was identified. The landing centres at Kumbalam, Nettor, Vypin and Mulavukadu were selected for the study. Fortnightly data on crafts, gears, and catch composition of both local and migratory fishermen were collected from these centres. The information collected about the crafts used by the fishermen include various technical details such as material, length overall (LOA), beam, draft, type of construction, preservatives used and engine used. Design details about the gears used such as type of material, its specifications, ropes, sinkers, floats, hanging coefficient etc., were collected. It was observed that while the migratory fishermen use only coracle as the fishing craft, local fishermen depend on plank built canoe with or without fibre coating. Outboard motor is used by many of the local fishermen for propulsion but the coracles of the migratory fishermen are propelled manually with oars. Migratory fishermen use only bottom set gill nets known as ‘Njandu vala’ targeting crabs,‘Karimeen vala’ targeting pearl spot (Etroplus suratensis) and ‘koori vala’ for other bottom dwelling fishes. Different types of gillnets used by the local fishermen like surface drift gillnet, ‘Ozhukuvala’ and ‘Thirutha vala’ and the bottom set gill net “Njandu vala’. All the nets are made up of Nylon mono filament, 210Dx1x2 except Njandu vala which is made up of 210Dx2x3.Mesh size for ‘Njandu vala’ of migratory fishermen and local fishermen vary from 90 to 150mm, and with a twine diameter of 0.2mm. The mesh size of ‘Thirutha vala’ ranged from 70-150mm and that of “ozhuku vala’ from36 to 120 mm. The ‘Karimeen vala’ has a mesh size of 40 to 60mm and for ‘Koori vala’ it was between 50 mm and 70 mm. The twine thickness for all these nets was 0.1 or 0.2 mm. The Hanging co-efficient was 0.3-0.7 for ‘Njandu vala’, of the local fishermen and 0.6 for the migratory fishermen, ‘Thirutha vala’ hanging coefficient 04. To 0.7, karimeen vala 0.4-0.6, ,Ozhukuvala hanging coefficient 0.46 and that for ‘Koori vala’ 0.5 to 0.6. The migratory fishermen use lead sinkers made from lead sheet in their nets. For Njanduvala the weight of the sinker is 8g and for other nets 5g. Local fishermen use electric wire of 5mm thickness as the foot rope, this acts as the sinker also for the surface drift nets ‘ozhukuvala’ and ‘thiruthavala’, for the bottom set ‘Najanduvala’ they use additionally some rocks and concrete sinkers also. The migratory fishermen set their in a zig-zag manner, were as the local fishermen set nets in a straight line. The mean monthly CPUE for local and migratory fisherman are 11.55kg and 24.61kg respectively. It indicates that catch and resultant income is more than double in the case of migratory fishermen compared to the local fishermen. In the techno-economic analysis payback period is the period required to recover back the original amount invested. The payback period is 5.4 months in case of the local fishermen where as it is only 1.8 months in case of migratory fishermen. Internal rate of returns (IRR) worked out to be 210.03% in case of local fishermen and 680.50% for migratory fishermen. The payback period and IRR indicate that migratory fishermen are safer in the recovery of original investment and are also in earning maximum profit.