基于BP神经网络的西北太平洋柔鱼资源丰度预测

柔鱼是具有巨大开发潜力的重要经济头足类种类,广泛分布在太平洋海域。柔鱼是短生命周期种类,其生活史过程与栖息地的海洋环境条件有重要关联,海洋环境因子的时空分布与变化显著影响着柔鱼资源的分布范围和资源密度。本文基于监督式学习算法的BP神经网络模型,综合多源卫星遥感观测获取得到的海表温度（Sea surface temperature;SST）、叶绿素a浓度（Chlorophyll-a concentration;Chl-a）、海表面高度距平（Sea surface height anomaly;SSHA）、海水质量变化和地转流等海洋环境因子,对西北太平洋柔鱼资源丰度的时空分布进行了模拟和预测。以上海海洋大学中国远洋渔业数据中心2004~2017年的西北太平洋海域的柔鱼历史渔业捕捞数据为参考值,对基于多源卫星遥感观测的多海洋环境因子的柔鱼资源丰度的模拟和预测结果进行了精度评定。结果表明,与仅采用SST、Chl-a和SSHA等进行柔鱼资源丰度时空分布预测的传统方案相比,进一步加入海水质量变化和地转流后,可有效提高利用BP神经网络对西北太平洋柔鱼资源丰度进行模拟和预测的精度：改进方法模拟的标准差（Standard deviation; STD）和均方根误差（Root mean square error; RMSE）均提高了22%;且预测的STD提高了31%,RMSE减少了26%。     

A multispecies approach to subsetting logbook data for purposes of estimating CPUE

An initial step in catch and effort analysis is determination of what subset of the data is relevant to the analysis. We propose an objective approach to subsetting trip records of catch and effort data when fishing locations are unknown; the species composition taken on a fishing trip is used to infer if that trip's fishing effort occurred in a habitat where the species of interest (the target species) is likely to occur. We use a logistic regression of multispecies presence–absence information to predict the probability that the target species would be present. A critical value of probability that best predicts target species presence and absence in the data set forms an objective basis for subsetting the trip records. We test this approach by applying it to a data set where individual fishing locations are known, and we show that the method is an effective substitute for information on individual fishing locations.     

Is model selection using Akaike’s information criterion appropriate for catch per unit effort standardization in large samples?

ABSTRACT:   Akaike's information criterion ( AIC ), which is widely used as a criterion of model selection in fish population dynamics, is known to have a bias in not only small samples but also large samples. Consistency was proposed as a property of the information criteria available in large samples. We carried out model selection in ANOVA-type model corresponding to catch per unit effort (CPUE) standardization using consistent information criteria (Bayesian information criterion, Hannan–Quinn, or consistent AIC ), which satisfy the asymptotic desirable property called consistency. The results of the model selections between these consistent criteria and AIC are different. Computer simulations using a linear regression model show that the selection performances of consistent information criteria in large samples are good compared with that of AIC .     

Dynamics of floodplain fisheries in Bangladesh, results of 8 years fisheries monitoring in the Compartmentalization Pilot Project

Floodplain fisheries were monitored from 1992 until 2000 in the Compartmentalization Pilot Project in Tangail, Bangladesh. In permanent floodplains about 165 ± 28 kg ha^?1 of fish was caught annually. For seasonal floodplains, this figure was 83 ± 23 kg ha^?1 yr^?1. The fish catch exhibited a strong seasonal variation, with the highest catch in October, when the floodwater recedes towards the river, and the lowest catch during the dry season in April/May. The annual catch varied with the extent of flooding, with high catches in wet years and low catches in dry years. The extent of flooding was quantified through a Flood Index. Plotting the annual yields against this Flood Index provided a significant relation (P < 0.05), confirming the existence of a flood pulse. The fishing effort (f) and the catch‐per‐unit‐effort (CPUE) were significantly related (P < 0.05), whereby the fishing effort increased with increasing CPUE. The results are discussed within the frame of fisheries management in Bangladesh and highlight the need for long‐term data for proper evaluation of fisheries projects and the development of management schemes, and the difficulty of applying standard surplus production models in floodplain fisheries.     

Potential impacts of non‐native channel catfish on commercially important species in a Japanese lake,as inferred from long‐term monitoring data

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基于广义可加模型研究时间和环境因子对南极半岛北部南极磷虾渔场的影响

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印度洋中国大眼金枪鱼延绳钓渔业CPUE标准化

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南极磷虾渔业CPUE及其丰度估算适用性

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金枪鱼渔业中人工集鱼装置生态影响研究进展

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