南海春季月相、水深、作业时间与鸢乌贼CPUE的关系

Relationship between lunar phase, water depth and operation time and CPUE of purpleback flying squid(Sthenoteuthis oualaniensis) in South China Sea in spring

根据2015和2016年春季灯光罩网渔船分别在南海南部和北部海域作业的鸢乌贼产量数据,研究作业条件水深、时间和月相与单位捕捞努力量渔获量(CPUE)的关系。GAM模型分析,作业时间和农历日对CPUE的影响显著。结果显示,月光天时,0~999m水深范围CPUE较低;月黑天时,各水层CPUE变化不大,2500~2999m水深范围CPUE较高;作业时间在上半夜(21:00—23:00),CPUE较高,最高达399.4kg/网,下半夜(0:00—5:00)CPUE逐渐下降;月光天和月黑天产量差别较大,分别为267.0和321.6kg/网;厄尔尼诺现象在一定程度上影响了鸢乌贼资源量在各水层的变化。各作业条件对鸢乌贼CPUE影响的研究能够为渔场的寻找提供参考。

According to the yield data of the Sthenoteuthis oualaniensis in the southern and northern sea areas of the South China Sea in spring in 2015 and 2016, the present research was carried out to analyze the relationship between depth, working time and moon phases and CPUE under the condition of operation. From the GAM model analysis, we knew that the effect of operation time and lunar day on CPUE was significant. The results showed that CPUE is relatively low at the depth of 0-999 m under the water in the bright moonlight. When there was nomoonlight, the CPUE in each water layer changed little, and the CPUE at the depth of 2 500-2 999 m was relatively higher. When the working time in the first half of the night(21:00—24:00), the CPUE was higher, which wan up to 399.4 kg/net at most, and the CPUE gradually decreased in the second half of the night(0:00—5:00). There was a great difference in the yield between the bright moonlight and moonless night, which were respectively 267.0 kg/net and 321.6 kg/net. E1 Nino has impact on the changes of the S. oualaniensis resources in various water layers to a certain extent. The research on the effect of operational conditions on CPUE of the S. oualaniensis can provide reliable suggestions for fishing ground.