Growth and mortality of tor fish (Tor soro valenciennes 1842) in asahan river
Rumondang, Azizah Mahari
This study aims to determine the growth and mortality of tor fish in the River Asahan. The study was conducted for 4 months from December 2016 to March 2017 in the Asahan River which still includes headwaters areas; Administratively into the territory of North Sumatra Province. Fish sampling using fishing gear in the form of a length of three meters, gill net with three mesh (¾, 1.5 and 2 inch) with length of 20 m and width of 2 meters, and electrofishing. The study included field activities (sampling of fish) followed by sample measurements. Total mortality rate (Z) of Tor fish 4.09 per year with natural mortality rate (M) 0.66; The mortality rate due to catch (F) 3.43, so that the rate of exploitation is 0.84. The rate of exploitation of the Tor fish in the Asahan River exceeds the optimum exploitation rate value of 0.5.