西北太平洋柔鱼渔场分布与水温关系的研究

根据卫星遥感获取的海表水温和多年来我国在西北太平洋的柔鱼生产统计资料 ,探讨西北太平洋柔鱼渔场与水温分布特征。研究结果表明 ,15 0°E以西的柔鱼渔场 ,中心位置位于 4 1°N、14 6°E附近 ,渔场表层水温范围在 10～ 19℃之间 ,中心渔场表层水温为 13～ 18℃ ;15 0～ 16 0°E之间的柔鱼渔场 ,中心位置位于 4 2°0 0′N、15 5°0 0′E附近 ,渔场表层水温范围为 14～ 2 1℃ ,中心渔场表层水温约为 15～ 2 0℃。温度场特征分析显示 ,柔鱼中心渔场分布与冷水锋面、冷暖水切变锋面和暖水舌锋的变动密切相关。     

北太平洋柔鱼渔场的环境特征

采用棋盘式定点大面调查和中心渔场专项调查2种方式,于2001年5～8月对北太平洋柔鱼(Ommastrephesbartrami)渔场进行了渔业资源与渔场环境特征调查。调查范围为北太平洋152°00′E～171°00′W、39°00′N～43°00′N海域,渔场环境特征要素主要为各站点的温度、盐度、浮游植物、浮游动物和叶绿素a含量。调查海域的柔鱼资源密度采用渔场海域每个经纬度的单位捕捞力量渔获量表示。结果显示,北太平洋柔鱼中心渔场中部与西经渔场表温为18℃左右,100m水温为9℃左右;西部渔场表温为16～20℃,100m水温为7～8℃;在有温跃层海域的跃层面下易形成高产渔场。浮游动物生物量较高的海域与中心渔场的位置基本保持一致;浮游植物生物量较高的海域和叶绿素a含量高于0.1mg/m3的海域,以及它们东侧海域易形成高产渔场;盐度与中心渔场的关系不明显。     

浅谈西北太平洋鱿钓中心渔场的寻找

<正> 近年来,鱿鱼已成为我国渔业生产的重要对象,在远洋渔业生产中居重要地位。西北太平洋是世界重要鱿鱼渔场之一,也是我国鱿鱼产量的主要来源。然西北太平洋是范围十分广阔的渔场,从日本近海直至160°E,从40°N至44°N的广阔洋面都可发现柔鱼的踪迹,皆可形成渔场。航速为11节的捕鱼船,航行两昼夜,才能到达渔场。因此,西北太平洋光诱鱿钓中心渔场的寻找和发现对提高鱿钓产量是十分重要的。本文就如何寻找其中心渔场谈一点个人的看法。 1.通过接收各种水温图确定渔场的大体     

北太平洋柔鱼资源与渔场的时空分析

利用相关系数和灰色关联评价方法对1995-2001年北太平洋各海域鱿钓产量及其作业渔场进行时空分析,结果表明主要作业渔场分布在145°E～148°E、153°E～161°E海域,其产量约占各年总渔获量的70%～85%。从作业纬度来看,1999年以前主要产量集中在40°N～43°N海域,而2000和2001年则分布在39°N～41°N和43°N～45°N海域。相关系数分析表明,2000和2001年作业渔场和各海域产量比重均发生了较大的变化,特别是在160°E以西和170°E以东海域,而在1999年以前未发生较大变化。灰色关联评价表明,1998年北太平洋柔鱼资源状况为最好,而2000、2001和1996年较差,1999、1995和1997年处在中间水平。这与实际生产情况和海洋环境条件基本上是相符的。2000和2001年北太平洋资源状况下降,可能与150°E～160°E海域的柔鱼种群资源出现下降有关。     

东黄海鱿鱼资源及其利用现状

太平洋斯氏柔鱼(Ommastrephes sloani)又称太平洋褶柔鱼(Todarodes pacificus),俗称火箭鱼(以下简称鱿鱼),是一种经济价值较高的头足类。东黄海区鱿鱼资源丰富,渔场分布广泛。我国鱿鱼生产主要是拖网和流刺网,特别是拖网生产,渔期长,产量高,效益好。现将如何合理开发利用和保护鱿鱼资源作一探讨。     

东黄海鱿鱼资源及渔业管理建议

太平洋斯氏柔鱼(Ommastrephes sloani pacificus)又称太平洋褶柔鱼(Todorodes pacicus Steenstrup),俗称火箭鱼(以下简称鱿鱼)。鱿鱼是一种经济价值较高的头足类,其营养丰富,味道鲜美,是出口创汇的重要品种。东黄海区鱿鱼资源丰富,渔场分布面广。我国鱿鱼生产主要是拖网和流刺网,特别是拖网生产,渔期长,产量高,效益好。现将如何合理开发利用和保护鱿鱼资源作一探讨。     

东黄海鱿鱼生物学特性的初步分析

<正> 太平洋褶柔鱼(Todarodes pacificusSteenstrup 1880)原名太平洋斯氏柔鱼,以下简称鱿鱼,是珍贵的海产品之一。历年来,在东黄海的底拖网、流网和围网渔获物中经常出现鱿鱼,由于50～70年代渔业资源较好,未引起人们的重视。80年代以来我国的渔业资源出现严重衰退现象,随着我国《渔业法》的颁布实施,禁渔线和禁渔期的划定,传统的底拖网渔场上每年第三季度几乎到了无鱼可捕的地步。在这种情况下,烟渔公司率先开发     

东海黄海头足类资源量的评估

本文用1996年、1997年浙江温岭渔7515、754两艘单拖渔轮的调查资料,采用资源密度面积法,对26°30′～30°00′N122°～126°30′E、20～150m水深海区的头足类的资源量进行评估。评估结果是:调查海区头足类资源量1996年为29055.84t,其中太平洋褶柔鱼为353.36t,剑尖枪乌贼为10734.10t,乌贼类为12384.9t,章鱼为5583.45t;1997年为35004.52t,其中太平洋褶柔鱼为1176.04t,剑尖枪乌贼为20511.30t,乌贼类为9658.50t,章鱼为3658.69t。东海区头足类资源量1996年为131747.81t,其中太平洋褶柔鱼为1602.24t,剑尖枪乌贼为48671.60t,乌贼类为56157.00t,章鱼为25317.02t;1997年为189441.07t,其中太平洋褶柔鱼为6364.61t,剑尖枪乌贼为111005.17t,乌贼类为52270.87t,章鱼为19800.48t。     

北太平洋柔鱼渔场浮游动物数量分布及与渔场的关系

根据2001年6-7月在北太平洋152°E～171°W、39°～42°N水域生态环境和资源综合调查资料,分析结果表明调查水域浮游动物总生物量均值为92.12mg·m-3(0.81～1035.68 mg·m-3),其中中部(160°～180°E、39°～42°N)及西经水域(170°～178°W、40°～41°N)为113.51mg·m-3,西部水域(152°～157°E、41°～43°N)为22.89mg·m-3;桡足类丰度居首(42.11%),其次为海樽类(30.91%);伪细真哲水蚤(Eucalanus pseudattenuatus)、太平洋哲水蚤(Calanus pacifica)和软拟海樽(Dolioletta gegenbauri)为主要优势种.甲壳类的分布与柔鱼中心渔场存在较好的对应关系,中心渔场位于浮游动物总生物量高密集区(250～500mg·m-3)和甲壳类的最高丰度区(50～100 ind·m-3)内或边缘区;头足类幼体分布于磷虾类和端足类的高丰度区(10～25ind·m-3)内或边缘水域.     

北太平洋150°～165°E海域柔鱼鱿钓渔场及其预报模型研究

根据1998-2000年8～10月在150°～165°E海域我国北太平洋鱿钓生产数据以及海况资料,分析柔鱼中心渔场与海洋环境之间的关系,建立柔鱼渔场预报模型。结果显示,黑潮势力的强弱及其分支分布与柔鱼渔场形成关系密切。8～10月柔鱼作业渔场基本上处在黑潮第2、第3暖水分支的前锋。柔鱼渔场分布与月份、20℃等温线分布的关系密切。8～10月中心渔场的预报模型为:经度方向FGLong=141.535+1.8435×T;纬度方向FGLati=-8.461+1.165×T+(Lat155+Lat160)/2。     

浅谈海洋捕捞技术的科学研究问题

<正> 海洋捕捞是一门综合性的应用技术科学。其范畴包括捕捞对象、渔场、渔具和渔法以及技术管理。广义而言,尚包括渔船、渔业机械和探鱼仪器,以及捕捞作业中进行渔具性能测试的有关仪器。然而,其核心应是研究渔具和渔法对捕捞对象习性行动和渔场环境条件变动的适应性问题。亦即以渔法     

Fishing rights auctions in the fisheries of Lake Peipsi-Pihkva, Estonia

Abstract  To deal with excessive fishing capacity, a part of the fishing rights, both volume quotas and gear use rights, in all Estonian fisheries was allocated each year during 2001–2003 through auctions while the remainder was allocated on the basis of the recent fishing rights use history. All fishing rights depreciated in a geometric manner by 10% annually. This was carried out for the first time in 2001, but the system was abandoned for political reasons in 2003. In this paper, the development of the small-scale Estonian inland fisheries, as well as the results of the auctions of fishing rights in those fisheries, are discussed. The auctions led to some increase in the number of owners of fishing rights. In most cases, however, new enterprises were formed on the basis of fishers active up to 2001 as employees of other enterprises. The auctions did not lead to a concentration of ownership of fishing rights in large enterprises. On the contrary, the share of smaller owners increased. According to the Fishing Act, in Estonia there is a fishing fee for all professional fishing gears. The official fishing fee was always used as the starting price in bidding, and this increased greatly during the bidding. Finally, the auction system served as a real incentive for fishers to cooperate more than they did during the previous management system based only on earlier rights.     

Stock assessment of the blue jack mackerel,Trachurus picturatus,in the North‐eastern Atlantic

A total of 49,151 blue jack mackerel, Trachurus picturatus, (Bowdich) was collected in Madeira Island (North‐eastern Atlantic) between 2002 and 2016 to evaluate possible influence of fishing on landings and reproductive parameters. A decreasing trend in the length composition was observed over the study period and length at first maturity decreased by 2.78 cm TL. Maximum yield per recruit decreased from 2002 to 2016 but the corresponding fishing mortality was constant (F_max = 0.4/year). Considering the fishing mortality level in 2016, it is evident that the stock may be exploited beyond its sustainability limit. Amendments of the purse‐seine fishing regulations and implementation of measures to reduce fishing effort are suggested.     

泉州市渔船历史沿革及今后发展方向

渔船是渔民出海捕鱼的主要工具。从古至今,泉州海洋捕捞渔船的发展历程经历了三个阶段：木帆渔船时期、机帆渔船时期、钢质渔船时期。本文在对三种类型渔船发展历史沿革进行回顾的同时,重点对近20年来钢质渔船的发展变化进行总结,并对渔船目前存在的问题及今后的发展方向进行探讨。     

渔业协会、渔村社区组织及其渔业资源管理功能

改革开放以来,随着渔业经济的快速发展,我国的渔业发展面一临着渔业资源严重枯竭、渔业监管困难、渔民收入增长幅度放缓等诸多问题。为此学术界在渔业资源管理方法上提出了许多意见,同时也存在着一些分歧。文章通过理论推演,结合文献数据,探讨了渔村社区组织与我国渔业协会的关系,分析了包括渔业协会在内的渔村社区组织对渔业资源管理的作用,通过对代表性渔业资源管理理论的利弊分析,剖析了渔民协会等渔村社区组织的渔业资源管理职能。同时指出由于渔业协会在资源管理中具有重要作用,但因其自身也存在着一定局限性,因此,培育渔业协会、完善其资源管理职能,实行基于渔业协会等渔村社区组织的合作管理也就成为我国加强渔业资源管理的一种制度选择。     

珠海“蟹夹”渔具的调查分析

根据“蟹夹”的渔具结构和捕捞原理,将其定名为漂流延绳弹夹笼壶。介绍了“蟹夹”的捕捞对象和作业方式,对其渔具性能进行了分析,对“蟹夹”渔具管理提出了若干意见。     

Global fishing effort (1950–2010): Trends,gaps, and implications

According to a recent World Bank report, the intensification of global fishing effort and the ensuing depletion of marine fish stocks causes economic losses of 50 billion US dollars annually. Data deficiencies, however, currently hamper analysis of global fishing effort. We analyzed data from the Food and Agricultural Organization of the United Nations (FAO), the EUROPA fishing fleet registry, and peer-reviewed and other publications, to determine the global trends in fishing effort from 1950 to 2006. Our results show that global fishing effort, expressed as total engine power and the number of fishing days in a year (kilowatt days), was roughly constant from 1950 to 1970, and then steadily increased up to the present. Europe dominated global fishing effort, followed by Asia. Projecting current trends suggests that Asia will soon surpass Europe. Trawlers contribute a major fraction of global fishing effort, as do vessels greater than 100 gross registered tons. Current estimates of global fishing effort, the number of vessels, and total vessel tonnage are, however, underestimates given the data gaps that we have identified. Our results are useful in the following ways: (1) they may encourage researchers in academia and government to improve global fishing effort databases; (2) they allow deeper global analyses of the impact of fishing on marine ecosystems; (3) they induce caution in accepting current underestimates of economic losses of global fisheries; and (4) they reinforce calls for a reduction in global fishing effort.     

Factors affecting the fishing power of sardine fishing vessels and implications for the management of the fisheries on Lake Kariba, Zimbabwe

Abstract The factors important in determining fishing power in the Lake Kariba sardine, Limnothrissa miodon (Boulenger, 1906), fishery were identified using data from the major fishing area of the lake, the Kariba basin, for the periods 1980–1982 and 1988–1990. Comparisons were carried out using fishing power calculated from the mean catch of some standard vessels. Three methods were used for identification of the important attributes. Analysis of variance (ANOVA) was carried out for each component to compare the mean fishing power at all levels within each variable. Multiple regression analysis was used to build predictive models and to determine the factors which best predict fishing power. Factor analysis was used to ordinate vessel types and examine any vessel groupings related to fishing power. Factor analysis showed that vessel and net size were the most important variables. Vessels without engines for propulsion, of low value and without radios had less fishing power than the other vessels in the fleet. Vessels from the same company had similar fishing power, suggesting that some unmeasured variable such as quality of management linked to the fishing companies had a significant effect on catch. The factors which were important in determining catch were length of vessel, depth of the net, presence and absence of echo sounder, mobility, the type of light, number and wattage of the underwater lights in the 1988–1990 fishing period. Vessel length and net category were most important in the period 1980–1982. The models accounted for between 37.6 (1981) and 61.2% (1988) of the variation in fishing power. During the development of the fishery, there has been a change from purse seine to lift nets, and increases in the use of echo sounders, engines for the propulsion of vessels and radios, all of which could have increased effective fishing effort.     

Attitudes and opinions of commercial fishermen on whitefish management in the Gulf of Bothnia, Finland

Abstract Catches of anadromous whitefish in the Gulf of Bothnia have declined since theearly 1990s. It is generally assumed that the cause is overfishing. The professional fishermeninterviewed in the present study were united in the opinion that it is necessary to set limits onthe fishing of whitefish, but had differing views about the means of achieving this. Thesedifferent arguments involved separate whitefish stocks, various types of gear and differentmotives for fishing. Most of the professional fishermen accepted a minimum mesh size for gillnets. Other means proposed included setting limits on non-professional fishing and sales ofcatches. There were conflicting attitudes about seasonal restrictions because their experienceswith fishing restrictions for salmon had been negative. On the whole, decision-making requiresmore regional information on whitefish stocks and fishing, but also on the social and economicflexibility of fishermen.     

黄渤海区日本枪乌贼渔获量预报方法初探

<正> 日本枪乌贼(Loligo japonica Steest-rup)在黄渤海区广为分布,渔获物主要胴长组成范围在70～120毫米之间,是一种一年生的广布性近海小型头足类。渔获量在万吨以上,但波动幅度较大。1970～1979年年平均渔获量5万多吨,波动于1.3～10.8万吨之间。其在黄渤海区冬春季底拖网渔业生产中常常以主要渔获种类出现,特别是在其资源状况较