铜山源水库渔获物组成与美国大口胭脂鱼的资源量估算

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2000~2002年每年的1月,在浙江省衢州市铜山源水库放养了前一年5月培育的美国大口胭脂鱼冬片鱼种,累计达1.6×105尾,于2004年11月,对用单层刺网捕获的渔获物进行了测量分析,并对所获渔获物中的美国大口胭脂鱼的年龄结构、可捕群体资源量、回捕率进行了分析估算.结果表明,铜山源水库渔获物中以白鲢为主,占总尾数的64.04%,总重量的78.2%;美国大口胭脂鱼次之,分别为29.55%和22.07%,而鲫鱼、鲤鱼等其他鱼类仅占7%左右.铜山源水库美国大口胭脂鱼由I~Ⅳ龄4个年龄组组成,其年龄结构中以Ⅱ、Ⅲ、Ⅳ龄为主,其可捕资源量达6.1×104尾、4.29×104kg,回捕率达36.8%;I~Ⅱ龄组为水库自然繁殖的子代群体,占所获美国大口胭脂鱼总尾数的40%,表明美国大口胭脂鱼在铜山源水库已自然繁殖并形成了一定的可捕捞资源量. From January 2000 to 2002, in January of each year, a total of 1.6 × 105 tails were collected from Tonghua source reservoirs in Quzhou City of Zhejiang Province in May of the previous year, which accumulated 1.6 × 105 tails. In November 2004, The monolayer catches of catch were measured and analyzed, and the age structure of the catch, the amount of catches and the capture rate of catches were analyzed and estimated.The results showed that the copper source Silver carp mainly occupied silver carp, accounting for 64.04% of the total mantissa and 78.2% of the total weight of the catfish in the catchment, followed by 29.55% and 22.07% of the U.S. catfish, while other fish such as carp and carp accounted for only 7% . The Tongshanyuan Reservoir is composed of 4 age groups of I ~ Ⅳ age, and its age structure is mainly Ⅱ, Ⅲ and Ⅳ, and the catastrophic resource of it reaches 6.1 × 104, 4.29 × 104kg, And the capture rate was 36.8%. The I ~ II group was the offspring of natural reservoir, accounting for 40% of the total mantis, which showed that the American rouladefish had naturally breed in the Tongshanyuan Reservoir and formed a certain amount of The amount of fishing resources.
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