전자저널 > 전자저널 > The study of stock assessment and management implications of the Manila clam, Ruditapes philippinarum in Taehwa river of Ulsan

The study of stock assessment and management implications of the Manila clam, Ruditapes philippinarum in Taehwa river of Ulsan

Young-Min Choi, Sang-Chul Yoon, Sung-Il Lee, Jong-Bin Kim, Jae-Hyeong Yang, Byoung-Sun Yoon, Jeong-Ho Park

Fisheries Resources and Environment Division, East Sea Fisheries Research Institute of NFRDI, Gangwon-Do, 210-861, Korea Fisheries Resources Management Division of NFRDI, Busan, 619-705, Korea External Research Cooperation Division of NFRDI, Busan, 619-

The manila clam (Ruditapes philippinarum) is mainly distributed in the coastal area which consist of mud, sand and gravel, but they rarely live on the upper and down reaches of river. For a long time the manila clam has been inhabited in Taehwa river which has been exploited as a traditional earning resources and has become as a major object by neighborhood fishermen. This study was undertaken to evaluate stock assessment and to build management implications with the ecological parameters in Taehwa river from June 2009 to June 2010. The maximum age of manila clam was determined to 6 years old from observing ring radius of shell, the length and weight relationship was TW = 0.0002SL3.063 (R2 = 0.925). K and L∞ were respectively estimated 46.64 mm and 0.341/year by von Bertalanffy growth. The instantaneous total mortality was estimated to be 1.171/year and the age at first capture was 1.37 years by the Pauly's method using shell length composition. The current total biomass of manila clam was calculated 1,483 mt over study area 1.46 km2 by swept area method. ABC (Acceptable Biological Catch) estimates of manila clam showed 512 mt with using F0.1. It's desirable to determine the optimum harvesting time as after main spawning season, as well as it's required to manage fisheries resources considering capture age and biomass through adjusting a first age at capture.

27_2_107-114.pdf (729.9K), Down : 403, 2011-08-23 18:33:50