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| Analysis of Effects of Fish Length Frequency Data on Estimates of Growth Parameters |
| YE Ting,WANG Ying-bin,ZHOU Cong-yu |
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Abstract Simulation data of 6 ages and 12 months were developed based on mackerel (Scomber j aponica) samples collected from the East China Sea during 2009 and 2010 .The impacts of length frequency biases , w hich usually come from the fishing selectivity or man‐made factors ,on the estimates of grow th parame‐ters (L∞ and K) when using FiSAT Ⅱ ,were analyzed .Scenarios of fewer smaller fishes and lack of larger fish were considered in the simulation analyses .The results showed that the larger fishes in the sample were critical to the accuracy of estimation .When there were fewer data or fewer smaller individuals in the samples ,the estimated L∞ and K were very close to the true values if the largest length group was availa‐ble .However ,when larger individuals were absent in the samples ,the estimated parameters were differed greatly from the true values .The estimated L∞ was smaller than the true value ,while K was larger . Therefore ,when FiSAT Ⅱ is applied to the estimation of growth parameters ,the distribution of length frequency in the sample should be accordance with that in the population ,and make sure that the largest length group is available in the sample .In this way , L∞ ,K ,and the abundance and catch in further as‐sessment can be accurately obtained .
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Received: 25 May 2014
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