Species composition and juvenile incidence in small mesh ring seine operated off Cochin, Kerala

Abstract

Ring seine is the most important and widely used fishing gear by motorized fleets along Kerala coast. It is locally known as ringuvala or kudukkuvala or ranivala or choodavala at different regions along the Kerala. A recent development in the ring seine fishery is the use of small mesh (8-10 mm size) gear operated in the near shore area at 13-18 m depth using plank built canoes of 9.6-12 m LOA. To assess the species composition and juvenile incidence in small meshed ring seine, a fishing village namely Chellanam located in southern part of Ernakulum District was selected. The village had as many as 55 small meshed ring seine units and three medium sized units. A detailed study was conducted to assess the species diversity, species composition, total catch and juvenile catch by small meshed ring seines operated in this area. Estimated total landings during the study period was 9.8 t. Of this, of 6.7 t was juveniles, viz., 68.21% of the estimated total landings was juveniles of which oil sardine formed 5.1 t by weight contributing to 76.11% of the juvenile catch. From the small meshed ring seine catch, 61 species were identified and recorded which include 53 species of fin fishes (belonging to 22 families), 5 shrimp species, one crab species and one cuttle fish species. Catch composition reveals that oil sardine, Sardinella longiceps forms 52% of the observed landings followed by Ambassids. Mesh size regulation of the gear would prevent juvenile fishery