大银鱼大面积增殖试验

在总面积６．６万亩的８个水库进行了大银鱼增殖试验。主要技术措施：移植前对水库调查，选择适宜投卵点，人工营造投卵场，清除水库内鲢鳙成鱼和凶猛鱼类，制订资源保护措施，规定禁渔区，禁渔期，捕捞网具和强度，留足供采集受精卵的亲鱼，采卵复投。结果：８个水库共捕大银鱼１３２．８ｔ，完成计划指标１７７％，纯收入９１７．２万元。完成计划指标２２９％，亩纯利１３８．９元，投入产出比为１：８．５，鉴定认为：大银鱼的大

Experiment on Reproduction of Protosalanx hyalocranius in Large Area of Reservoir

A reproduction experiment was made in 8 reservoirs with the total area of 66 thousand mu. The main technical measures were taken such as investigation of the reservoir before transplantation, choosing spot suitable for releasing fertilized spawns, man-made ground for releasing spawns,clearing away the silver carp, big head carp and ferocious fishes, laying down resource protection rules,making a regulation forbidding fishing zone and fishing period, prescribing fishing intension, reserving enough parent fish for collecting fertilized spawns to release again. The result showed: the output of Protosalanx hyalocranius in the eight reservoirs was l32. 8t,overfulfilled the plan quota 177 %,and the net income 9 million and 17. 02 thousand yuan,overfulfilled plan quota 229 %. The per mu net profit was 138. 94 yuan. The ratio of input and output was1: 8. 5. The result,appraised by experts,was in the lead in our country in the aspect of high yield in the large area for transplantation of Protosalanx hyalocranlus.