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Showing posts from 2017
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Marking and tagging for releasing activity Masatoshi FUTAGAWA August 27, 2017 Markers and tags The marking or tagging is essential activity in order to identify the released fish in the field. According to identification, we evaluate the activity such as growth, survival, migration of the fish at field and evaluate economic effect. Thus, it is necessary to announce to public that request to inform catch data about tag code, location and size of fish. ·          Nasal septum defect : Some hatchery made fish shows nasal septum defect, nose holes are connected. The data have to revising by the defect rate of the released fish batch. ·          Plucking fins / spines : Pluck ventral, pectoral fin or spine at dorsal fin. The method does not harm any survival and growth according to the paper . Even so, the mark recover within few years. ·          Anchor / darts tag : The tag has some number and letters, us
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The strategy of f infish culture founding in Chile (Revised version of April 28, 2012) Masatoshi FUTAGAWA August 9, 2017 Exportation of salmons and trout reduced to 513 thousand tons (-13%) and 3.8 billion USD (+8%) in 2016 compare to 2015 due to influence of toxic algae bloom.  Also, natural resource of coastal fishes are decreasing much due to overfishing, and affect costal life which happening in all over the world. Thus, it needs alternatives culture species of salmons to minimize risk of the business and recover resource of costal fishes to improve costal life. The keywords are “Economical sustainability”, “Minimum influence for nature” and “Less energy consumption”. 1.     Conditions 1.1. Fish characters Ideal habits for commercial culture are bellow. ·          Easy to produce juvenile ·          Grow fast; grow to marketable size in a minimum time ·          Wide tolerance of water change about WT, pH, DO, turbidity, ammonia and other chemical contam