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首页> 外文期刊>ICES Journal of Marine Science >Standardization of bluefin tuna, Thunnus thynnus, catch per unit effort in the baitboat fishery of the Bay of Biscay (Eastern Atlantic)
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Standardization of bluefin tuna, Thunnus thynnus, catch per unit effort in the baitboat fishery of the Bay of Biscay (Eastern Atlantic)

机译：蓝鳍金枪鱼（Thunnus thynnus）的标准化工作，在比斯开湾（东大西洋）的诱饵渔业中每单位捕获量

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Relative indices of abundance by age class for bluefin tuna from 1975 to 2000 were estimated using generalized linear mixed models. Age class was included as a fixed factor within the model specifications, with the Year x Age interaction as a fixed factor component in order to obtain annual indices by age. Catch and effort data on bluefin tuna were available from two sources, catches by trip, and daily catches from logbooks. Catches were modelled using the delta-lognormal model. The model finally selected included the following explanatory factors: Year, Age, Year x Age, Month, number of Crew, number of Bait Tanks, and with the Year x Month interaction as a random component. Overall, year trends and coefficients of variation were similar from both datasets by age class. In general, the standardization procedure showed that vessel characteristics and technological advances related to fishing have a relatively minor explanatory effect on the observed catch rates of bluefin tuna in the fishery. Neither geographical distribution nor type of bait had an explanatory effect on the observed catch rates. The 1994 cohort stands out as an exceptionally large year class; it can be followed through the standardized series. This standardized catch rate index at age of bluefin tuna is the most complete yet available and is the only one currently used for juvenile fish in calibrating population models to evaluate the Eastern Atlantic and Mediterranean stock. It is particularly valuable because, apart from improvements in electronic technology, there are no changes in the method of exploitation during the entire series.
机译：使用广义线性混合模型估算了1975年至2000年蓝鳍金枪鱼按年龄类别划分的相对丰度指数。在模型规范中，年龄类别作为固定因素包括在内，“年x年龄”交互作为固定因素组成部分，以便按年龄获得年度指数。蓝鳍金枪鱼的捕捞量和努力量数据可从两个来源获得：按行程捕捞，以及来自日志的每日捕捞量。使用增量对数正态模型对渔获量进行建模。最终选择的模型包括以下解释因素：年，年龄，年x年龄，月，乘员组数，诱饵箱数以及以年x月互动为随机成分。总体而言，两个数据集的年龄趋势和变异系数相似。一般而言，标准化程序表明，与捕捞有关的船只特性和技术进步对所观察到的蓝鳍金枪鱼捕捞率的解释作用相对较小。诱饵的地理分布和种类均未对所观察到的捕获率产生解释性影响。 1994年的同班同学在一年级中表现突出。可以遵循标准系列。蓝鳍金枪鱼年龄的这一标准化捕捞率指数是最完整的，并且是目前用于校准种群模型以评估东大西洋和地中海种群的幼鱼的唯一指数。它特别有价值，因为除了电子技术方面的改进外，整个系列中的开发方法没有任何变化。

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