月相对南海灯光罩网鸢乌贼渔获率的影响分析

Effect of moon phase on fishing rate by light falling-net fishing vessels of Symplectoteuthis oualaniensis in the South China Sea

根据同一艘灯光罩网船2006年~2010年3月~5月在南海西中沙海域的生产数据,利用广义加性模型（GAM）评价了月相对灯光罩网鸢乌贼（Symplectoteuthis oualaniensis）渔获率的影响,并利用方差分析方法（ANOVA）比较了月光天（农历初八至二十二）和月黑天（农历初一至初七、二十三至三十）之间作业天数和鸢乌贼平均日产量的差异。结果显示,GAM模型中各年份月相对灯光罩网鸢乌贼渔获率的影响极为显著（P〈0.001）;作业天数在月光天和月黑天之间存在显著性差异（P=0.004〈0.05）,在月黑天的作业天数明显高于月光天;平均日产量在月光天和月黑天之间也存在显著性差异（P=0.024〈0.05）,在月黑天的平均日产量也明显高于月光天。

Based on the production data of the light falling-net fishing vessels in Xisha and Zhongsha sea area from 2006 to 2010 （ March to May） , we investigated the effect of moon phase on fishing rate of Symplectoteuthis oualaniensis based on general additive model （GAM）. And the difference of the fishing days and the average daily catch between bright moonlight （8th -22nd, lunar calen- dar） and no-moonlight （23rd - 7th, lunar calendar） were analyzed by ANOVA analysis. The results show that the effect of moon phase on average daily catch of S. oualaniensis was remarkable by GAM analysis in every year （ P 〈 0. 001 ）. Significant difference was found in the fishing days （ P = 0. 004 〈 0. 05 ） and average daily catch （ P = 0. 024 〈 0. 05 ） in bright moonlight and no-moonlight, and the fishing days and average daily catch in bright moonlight were higher than those in no-moonlight.