Bioeconomic assessment of size separators in Pacific saury fishery

In the middle of the 1990s, Pacific saury fishery vessels began to install “size separators” to selectively land large-size class fish with a higher price. Contrary to expectations, this resulted in removal of the separators in 2006 because fishers believed the separators had contributed to price collapses in the 2000s. The intent of this paper is to investigate the effects of separators on both the fishery economy and stock of Pacific saury by simulating population and economic models under a single framework. For this purpose, we developed (1) an age-structured population dynamics model with stochasticity, and (2) an economic model spanning both price and inventory dynamics with stochasticity, in which each set of model parameters were estimated on the basis of time series data. In a 10-year simulation, the harvest quota was set constant from 20,000 to 400,000 t at intervals of 20,000 t, and the effects of separators were incorporated by controlling the catchability of 0-year-old fish. We found that separators increase the expected yield and reduce the deficit risk for harvests of 140,000 t and smaller. However, separators have the opposite effects for harvests of 160,000 t and larger.     

我国水产类高等院校微生物学实验教学改革

根据水产类高等院校微生物学实验教学的特点,分析了微生物学实验教学在教学内容、教学方法、教学评价等方面所存在的问题,进而提出了完善水产类高等院校微生物学实验教学的措施,即加强实验教学的重要性,提高教师自身的素质与实验教学的质量;优化实验教学课程,合理安排实验内容,提高学生的综合实验技能;充分利用现代教育技术,更新教学手段,激发学生的学习兴趣;建立以能力考核为核心的微生物学实验教学多元化的考核方式等。     

渔业科学知识体系和中国特色的渔业发展之路

渔业应定义为对水生生物资源进行开发利用及其相关经济和科技活动的产业,其渔业科学知识体系的形成始于近代渔业发展阶段。经过100多年的发展,渔业科学知识体系不仅包括渔业生物学、渔业捕捞学、水产养殖学,同时还包括由此带动起来的水产品加工与质量安全、渔业装备与工程、渔业经济与管理等学科。在中国,已从基础研究、水产教育和人才培养、推进产业科技进步等方面形成若干支撑渔业发展的重点学科领域。经过60多年的探索、徘徊、调整和创新,中国渔业走出了一条具有显著中国特色、以养殖为主的发展之路。展望未来,中国渔业必须遵循绿色发展理念,坚持渔业发展与生态环境保护协同共进,大力促进渔业生态文明建设,建设环境友好型水产养殖业和资源养护型捕捞业,促进增殖渔业和休闲渔业新业态的发展,以保证中国特色的渔业持续健康发展,为中国和世界做出新贡献。     

东海北部外海剑尖枪乌贼渔业生物学特征

根据2017和2018年的9月—翌年2月拖网渔船在东海北部外海采集的剑尖枪乌贼样本,研究其基础生物学特征。结果表明,个体的优势胴长和体质量组雄性分别为100～180 mm和40～160 g(n=309尾),雌性分别为80～160 mm和40～160 g(n=304尾),雌雄个体的胴长和体质量年间不存在差异。协方差分析(ANCOVA)表明,雄性个体体质量-胴长关系年间差异显著(P0.05),而雌性年间差异不显著(P0.05)。性成熟胴长雄性主要集中在大于120 mm的个体,雌性为大于140 mm的个体,并且呈现出较小体型下即可达到性腺成熟的趋势。雌性个体的胴长和体质量生长速率略快于雄性,并且雌雄个体的体质量生长率年间差异较大。综合分析认为:两年间采样的剑尖枪乌贼种群为春季和夏季产卵种群,2018年样本中夏季产卵种群的幼体数量较多。因此,研究剑尖枪乌贼渔业生物学动态特征是资源持续开发和渔业管理的基础。     

庆平湖的水生植被及其渔业利用

本文分析了庆平湖水生维管束植物的种类组成，植被类型，生物量及其渔业利用潜力。该湖水生维管束植物共有１４科１６种，优势种为芦苇，菹草，狭叶香蒲，小茨藻等。植被类型可划分为三个亚型，全湖有７个主要植物群丛，水生植物总生物量为４９６８ｔ，以植物生产量计草食性鱼类年生产力约为１３３８２．５ｋｇ。并对该湖水生植被特点及渔业利用问题进行了讨论。     

Multiple otolith techniques aid stock discrimination of a broadly distributed deepwater fishery species, blue grenadier, Macruronus novaezelandiae

This study investigated otolith shape, elemental chemistry of otolith cores (first 1-3 months of life), and stable isotope ratios (δ¹⁸O and δ¹³C) of whole otoliths as indicators of stock structure among three important southern Australian blue grenadier Macruronus novaezelandiae fishery regions; west Tasmania - WTAS, east Bass Strait - EBS, and Great Australian Bight - GAB. Comparisons were confined to two dominant cohorts of age 4+ and 13+ years, spawned in winter 2002 and 1993 respectively. Otolith shape varied significantly between the WTAS and GAB regions for the age 4+ cohort only. Cu:Ca of otolith cores was significantly higher for both cohorts from WTAS than EBS and GAB, and Ba:Ca of otolith cores higher for WTAS and EBS than the GAB region. Stable isotopic signatures showed greater variation among regions for the age 13+ cohort. In particular, otoliths of age 13+ fish from WTAS displayed significantly higher δ¹⁸O (indicative of lower temperature history) than age 4+ fish from all regions, and the same age fish from the GAB and EBS regions. δ¹⁸O of blue grenadier otoliths accurately predicted water temperature at their main capture depths of 400-600 m. Chemistry of otolith cores combined with whole otolith isotope ratios discriminated GAB and EBS samples from those collected on the known WTAS spawning ground with moderate to high (64-86%) accuracy. The results provide support for the hypotheses that the GAB fishery is based on a separate stock for management purposes, and that the EBS fishery is likely replenished both from local spawning and the major WTAS spawning region.     

七带石斑鱼的形态和生物学性状

2010年在广东省饶平县柘林湾进行了七带石斑鱼（Epinephelus septemfasciatus）海水网箱人工养殖研究,观察和研究了人工养成的七带石斑鱼的形态特征和生物学性状。通过观察、测量、解剖,对114尾七带石斑鱼的外部形态、可量比性状和内部结构进行了研究。结果表明,七带石斑鱼体呈椭圆形,侧扁,体侧具7条褐色横带,第1条横带仅伸达主鳃盖骨上方边缘,第6条横带分成2条,体侧横带具有不规则的白色斑纹,各鳍边缘白色,背鳍鳍棘部褐色和白色横带相间,鳍条部具有由白色横带延伸而成的3个白斑。胃呈卜型,幽门盲囊发达;肠道长度为体长的0.7～1.4倍,与七带石斑鱼为肉食性鱼类的特征相一致。     

Management strategy evaluation: best practices

Management strategy evaluation (MSE) involves using simulation to compare the relative effectiveness for achieving management objectives of different combinations of data collection schemes, methods of analysis and subsequent processes leading to management actions. MSE can be used to identify a ‘best’ management strategy among a set of candidate strategies, or to determine how well an existing strategy performs. The ability of MSE to facilitate fisheries management achieving its aims depends on how well uncertainty is represented, and how effectively the results of simulations are summarized and presented to the decision‐makers. Key challenges for effective use of MSE therefore include characterizing objectives and uncertainty, assigning plausibility ranks to the trials considered, and working with decision‐makers to interpret and implement the results of the MSE. This paper explores how MSEs are conducted and characterizes current ‘best practice’ guidelines, while also indicating whether and how these best practices were applied to two case‐studies: the Bering–Chukchi–Beaufort Seas bowhead whales (Balaena mysticetus; Balaenidae) and the northern subpopulation of Pacific sardine (Sardinops sagax caerulea; Clupeidae).     

灯塔市渔业可持续发展评价指标体系的构建及评价

为了准确量化和科学评价灯塔市渔业可持续发展能力及影响因素,保证其渔业发展对当代有利、对后代负责。在参照相关研究成果的基础上,结合灯塔市的实际,收集整理了该市渔业2000—2010年共11年的指标数据,构建了包括经济、环境、资源和社会4个子系统、16个指标的可持续发展综合评价指标体系。并以2000年为基准年,计算出了10年各指标相对于基准年的变化率,采用加权综合的计算方法进行综合评价。结果表明：2000—2010年间灯塔市各项渔业指标基本上都处于递增状态,可持续发展能力建设取得了一定的成绩,渔业可持续发展总体上朝着有利于渔业可持续发展的方向变化。研究结果对于全面了解灯塔市渔业发展综合竞争力,促进其渔业全面、协调、可持续发展具有重要意义。