基于BiLSTM模型的远洋渔船类型识别研究

船舶自动识别系统(Automatic identification system,AIS)为渔业资源和渔船捕捞活动管理和研究提供了可能.明确船舶作业类型是开展AIS信息渔业研究应用前提,为渔业研究和管理提供渔船捕捞类型基础数据支撑,保障渔船作业安全和监督非法捕捞渔业活动,作者通过搜集整理3000多艘已知类型船舶信息,从...     

ENSO现象与台湾海峡西部海区中下层鱼类渔获量关系

对台湾海峡西部海区中下层多年（1956－1973年）渔获量变化与EN现象关系并结合捕捞强度进行一些初步分析，总结出渔获量变化规律，为合理开发渔业资源提供有用信息。     

利用元胞自动机探讨商业性CPUE与资源量之间的关系

构造1个集鱼类资源增长、渔船捕捞及鱼群分布与渔船作业间相互作用的元胞自动机模型,以探讨鱼群探捕与渔船作业可能对商业性CPUE与资源量之间关系的影响.文中分别模拟了(1) 鱼群集中或随机分布,渔船随机分布;(2) 鱼群由随机逐渐集中,渔船通过捕捞数据也逐渐集中分布,同时规定每艘船的最大捕捞量;(3) 鱼群由分散到集中再到分散,而渔船集中在鱼群分布概率最大区;(4) 渔船从随机分布到逐渐集中分布,鱼群集中分布不变等4种渔业上客观存在的情形.在渔船随机分布的情形下,不管鱼群如何分布,商业性CPUE与资源量均呈线性关系;在鱼群分布逐渐集中、渔船由于渔民经验积累也随之逐渐集中的情形下,商业性CPUE与资源量能表现出高稳性和高贫化性的特点.由于鱼群的集散或渔船进入渔区的时间长短不一,会造成商业性CPUE与资源量负相关的现象.上述模拟情况说明,在渔业资源评估中需要关注模型应用的前提条件以及模型的完善.文中还探讨了元胞自动机在渔业资源评估中应用的可行性.     

我国主要海洋捕捞政策对浙江省海洋捕捞业的影响探究

随着海洋渔业资源的不断衰退,为了保护渔业资源、推动海洋渔业的可持续发展,自20世纪70年代后期,我国出台了许多海洋捕捞相关政策。文章从投入控制制度、产出控制制度和技术控制制度3个角度出发,以捕捞许可制度、捕捞限额管理和伏季休渔制度等政策为重点,通过整理1980—2017年浙江省渔业经济的相关资料,从海洋捕捞渔船数量和功率、海洋捕捞产量、渔业劳动力数量变化3个方面,深入分析浙江省海洋捕捞现状,提出了完善现有的海洋捕捞政策、加强渔业执法管理力量、加强普法宣传、建立渔业资源调查与评估体系、帮助捕捞从业人员转产转业等对策建议,以期为我国海洋捕捞管理部门提供决策参考。     

基于渔业捕捞产量的监测渔船数量优化

海洋捕捞活动数据是渔业资源评估与管理的基础,监测渔船数量的设置需要兼顾保证数据质量和降低监测成本。本研究基于2017年浙江省海洋捕捞抽样调查数据,采用分层随机采样和计算机模拟再抽样方法,以小黄鱼(Larimi-chthys polyactis)、带鱼(Trichiurus lepturus)、海鳗(Muraenesox cinereus)等9种经济种类的单船月捕捞产量以及所有9种渔获总产量作为渔业生产监测目标,以相对估计误差(REE)、相对偏差(RB)作为评价指标,分析了渔业生产监测船数量对渔业生产监测目标估计精度的影响。研究表明：各物种的单船月捕捞产量以及总产量估计值的REE和RB随着监测渔船数量的增加而下降,当渔船数量少于110时REE值下降幅度较快,当渔船数量多于110时REE值下降幅度减缓并趋于平稳。分析每增加10艘监测渔船时REE的减少量,发现当渔船数量为70时,各研究目标产量估计值的REE减少量均小于5%,此时监测渔船总数量减少了73.28%;当渔船数量为110时,各研究目标产量估计值的REE减少量均小于1%,此时监测渔船渔船点数量减少了58.11%。研究结果表明,在兼顾调...     

厦门海域渔业资源评估

以初级生产力和渔业统计资料为材 ,分别应用Tait沿岸海域生态系能流分析法、营养动态法和Cushing等 3种模式 ,估算厦门沿岸海域的渔业资源自然生产量。同时 ,分别应用Schaefer和Fox两种剩余产量模式估算最大持续产量和最大持续捕捞力量。前 3种模式估算该海域的资源生产量分别为 2 0 1 0 5t,1 8463t和 1 7489t,平均 1 8686t。后两种模式估算最大持续产量平均值分别为 9639t和 91 0 4t。估算的最大持续捕捞力量 :5种作业综合总功率为 1 5976kW ;以厦门机定置渔船单位功率渔捞效率为标准估算的总功率为 2 7351kW ;以厦门机刺网渔船单位功率渔捞效率为标准估算的总功率为 432 1 3kW。 1 997年实际渔获量和捕捞力量均超过了估算的最大持续产量和最大持续捕捞力量。文中还讨论了捕捞力量的调整问题。     

厦门沿岸海域渔业资源变化和最适捕捞力量的估算

本文以厦门沿岸海域历次渔业资源和生物调查及１９８４－１９９５年渔业统计资料为背景,分析了该海域渔业资源的变动,重点对文昌鱼、真鲷、鳓鱼、大黄鱼、蓝点斑马鲛、长毛对、中国鲎等重要经济种类资源变动的原因进行探讨,针对目前资源的变动趋向,指出了近期重点的保护对象和有开发潜力的种类,并以三种标准捕捞力量,应用了Ｓｃｈａｅｆｅｒ和Ｆｏｘ两种剩余产量模式估算最大持续产量（ＭＳＹ）和最知捕捞力量。估算结果ＭＳＹ     

意大利远洋捕捞船队

意大利远洋捕捞船队有渔船41艘,共计30700吨。其中低于500吨的15艘;500—1000吨的15艘;1000吨以上的11艘。远洋船队共雇用1200名海员。意大利有12艘渔船在北美水域作业,其它船只分布在安哥拉,尼日利亚、贝宁、塞拉利昂、几内亚、几内亚-比绍、塞内加尔和索马里。根据欧洲经济共同体方面的协定,意大利有15艘渔船在塞内加尔、几     

海洋捕捞与海水养殖监管系统研究

文章针对海洋渔业由于过度捕捞造成渔业资源枯竭的问题,提出了一种基于海洋遥感(ORS)、全球定位系统(GPS)和海洋地理信息系统(MGIS)等高新技术的海洋捕捞与海水养殖监管系统设计方案,可以远程自动对海洋渔业区域的水质多参数信息和养殖环境视频信息进行综合采集、传输及监控,也可以自动采集传输渔船RFID身份识别信息、渔船AIS自动识别信息、渔船GPS定位信息和捕捞生产视频信息等,并通过海洋精细渔业专家系统ES进行渔业养殖监控、渔业环境资源监测评估、渔船船数和功率数控制和海洋捕捞生产渔情监测等。该系统可以实现海洋渔业精细化捕捞和海洋渔业精细化养殖,促进海洋渔业可持续发展。     

台湾海峡及其邻近海域渔业资源的管理

应用Ｓｃｈａｅｆｅｒ和Ｆｏｘ剩余产量模式及其由此衍生的生物经济模式和Ｇｕｌｌａｎｄ最适产量Ｙ０．１模式,分别估算了台湾海峡及其邻近海域渔业资源的最大持续产量、最大持续捕捞力量,并对各模式计算的诸项经济指标进行比较,讨论了渔业管理方案,确定了近期适合国情,并对各模式计算的诸项经济指标进行比较,讨论了渔管理方案,确定了近期适合国情、省情的管理目标。     

台湾海峡灯光围网渔船的技术经济分析

本文系根据1980～1989年福建省在台湾海峡生产的48组具有代表性的标本船之技术经济资料,以柯布·道格拉斯生产函数和经济指标评析其生产状况及技术经济效果。结果表明,近年来,福建省灯光围网渔船的宏观技术水平已明显提高;然而因其捕捞努力量大幅度增加,单位捕捞努力量渔获量曲线呈抛物线状,其长期趋势为CPUE=-0.311+0.9032f-0.06397f~2;预测投资在功率范围为147～294kW的灯光圈网渔船在台湾海峡生产可望受益。     

Second-guessing uncertainty: Scenario planning for management of the Indian Ocean tuna purse seine fishery

An important task of natural resource management is deciding amongst alternative policy options, including how interventions will affect the dynamics of resource exploitation. Yet predicting the behaviour of natural resource users in complex, changeable systems presents a significant challenge for managers. Scenario planning, which involves thinking creatively about how a socio-ecological system might develop under a set of possible futures, was used to explore uncertainties in the future of the Indian Ocean tuna purse seine fishery. This exercise stimulated thinking on how key social, economic and environmental conditions that influence fleet behaviour may change in the future, and how these changes might affect the dynamics of fishing effort. Three storylines were explored: an increase in marine protection, growing consumer preference for sustainable seafood, and depletion of tuna stocks. Comparing across several possible future scenarios, a number of critical aspects of fleet behaviour were identified that should be important considerations for fishery managers, but which are currently poorly understood. These included a switch in fishing practices, reallocation of effort in space, investment in new vessels and exit from the fishery. Recommendations for future management interventions in the Indian Ocean were offered, along with suggestions for research needed to reduce management uncertainty.     

Adaptation of fisheries and mariculture management to extreme oceanic environmental changes and climate variability in Taiwan

This study presents the response of fisheries management to the extreme climatic events that affect marine capture fisheries and mariculture in Taiwan. Two regional approaches that can be applied universally to help capture fisheries and mariculture adapt to extreme weather events are also proposed. In the winter of 2008, an anomalously strong and continuous northeasterly wind caused by a La Niña event drove the cold China Coastal Current southward to penetrate the southern Taiwan Strait, and a portion of this current intruded eastward to the southern Penghu Archipelago. The cold current intrusion appreciably damaged marine aquaculture and the wild fish population, causing the death of more than 73 t of wild fish and 80% of cage aquaculture fish at the Penghu Islands. This extremely cold seawater event occurred between late January and the beginning of February 2008. To recover fishery resources around the waters of Penghu, fishery-related agencies adapted recovery measures over 3 years starting in April 2008 that included hatchery juvenile release, environmental monitoring, fishery subsidies, and ecological field investigations. This study suggests that responding to extreme climatic influences on fisheries and mariculture should include (1) establishing an early warning system by connecting fisheries agencies and marine research institutions to assist decision makers in performing time-adaptive measures, (2) temporarily suspending fishing activities after the occurrence of a natural disaster to help recover fishery resources and ecosystems, (3) altering the governance of farming fishing right so that fish farmers can temporarily transfer their aquaculture cages from high-risk areas to waters outside the influence of extreme weather events, and (4) continually filing surveys to understand the recovery status of marine ecosystems.     

An empirical analysis of the economic value of ocean space associated with commercial fishing

Understanding the economic value of ocean space is critical for implementing marine spatial planning (MSP). Empirical data from 1999 to 2008 are compiled on the economic values arising from commercial fishing in the Gulf of Maine and adjacent areas. The data are analyzed to characterize factors affecting the spatial and temporal distribution of measures of economic productivity and fishing effort. The analysis consisted of four components: (1) estimation of net revenue at the 10-min square level by season and gear; (2) assessment of variability for catch revenue and catch per unit effort; (3) mapping net revenue and variability in the study area; and (4) estimation of interactions among catch, effort, season, and gear type. The results indicated that, at each location, average fishing efforts exhibited a positive response to increases in expected revenues and a negative response to variability in revenues. Most of the variability in catch revenue can be explained by changes in fishing effort, implying that the spatial patterns of fishery resources are relatively stable at the 10-min square level. An important conclusion is that a spatial scale of at least the 10-min square is appropriate for undertaking MSP involving allocations of commercial fisheries.     

Precious coral fisheries management in Taiwan—Past,present & future

Taiwan used to have the biggest precious coral fisheries industry in the world. However, due to changes in the fishery, including increased fishing restrictions and the replacement of obsolete vessels, the scale of the industry had been gradually reduced since 1979. Unfortunately, the initiative proved to be poorly managed and resulted in an increase in illegal, unreported and unregulated (IUU) coral fishing. This forced the government to review and amend the precious coral fisheries management regulations, which had been in place for decades. The Taiwanese government introduced stringent monitoring, control and surveillance (MCS) management methods, already used in deep water fisheries, as a precautionary approach. At the same time, an investigation and evaluation of existing resources was carried out. Together, these initiatives were introduced in order to encourage the domestic industry to adopt the concept of ecosystem-based fishery management.     

Management of the precious coral fishery in Taiwan: Progress and perspectives

Precious corals have been commercially exploited because of their legendary and cultural importance for many centuries in the Mediterranean and for almost one century in the Northwest Pacific. Although the precious coral fishery in Taiwan dates back to the 1920s, relevant studies on biology and ecology of resources are relatively scarce. The management of the precious coral fishery in Taiwan was officially instituted in January 2009, when data on the catch and effort of the fishery were recorded. In this study, the catch-effort data of the fishery were examined to explore the temporal and spatial patterns in composition and abundance of Corallium and Paracorallium spp. around Taiwan. A total landing of 3233.0 and 2906.8 kg precious corals were recorded for 2009 and 2010, respectively. Less than 5% of those amounts were from live colonies. A high proportion of fossilized colonies in the catch reflect the non-selective nature of the fishing gear; however, the factors that cause colonies to collapse are not exclusive to the impact of the fishery. Momo coral was dominant in the production for both years, followed by Miss coral. The total production of precious corals correlated positively with fishing efforts, while a weak relationship was found between the production of live colonies and fishing efforts. The fishing efforts mainly aggregated in designated fishing ground A (DFG-A) for both years, while the production of live colonies mainly occurred in DFG-E. The monthly occurrence rate of live colonies decreased over the past 2 years. Although fluctuating significantly, the CPUE of dominant species exhibited an apparent decreasing pattern. High aggregation of the fishing efforts in specific regions and low numbers of live colonies in the production should be carefully taken into account when amending management regulations in the future. The establishment of marine protected areas, in addition to the strict controls that already apply, should be considered to not only sustain the population structure of the sessile animals but also their function in the marine ecosystem.     

基于船位监控系统的拖网捕捞努力量提取方法研究

为了基于船位监控系统提取拖网捕捞努力量,通过统计航速获得3个峰值,拖网作业在第2个峰值,即1~2.1 m/s,拖网作业航向差一般在–50°~50°。利用航速、航向差阈值设定,把拖网船状态划分为慢速、作业、航行,然后提取出捕捞作业状态点,1 423艘拖网船共提取到处于捕捞状态的点318 433个,合计拖网捕捞时间15 921 h,利用反距离加权插值法生成捕捞强度分布变化趋势图。捕捞努力量在渔业资源研究中是重要的参考值之一,与传统的捕捞努力量计算方法相比,该方法具有实时、大范围、快速、分辨率高的特点,能够用于辅助渔业资源保护。     

Improving fleet efficiency to maximise economic yield in a Western Australian prawn fishery

The Shark Bay trawl fishery is Western Australia's most valuable prawn fishery (worth AUD$25 million in 2014). The 18-vessel fleet targets western king prawns (Penaeus latisulcatus), brown tiger prawns (P. esculentus) and also retains saucer scallops (Ylistrum balloti) and blue swimmer crabs (Portunus armatus). Increased fuel prices, falling prawn prices and lower catches of other species, following extreme environmental events, have impacted fishery profits. A biomass dynamics model with an economic component indicated that total revenue levels start to decline when annual effort increases beyond ~ 200 fishing days per boat. Annual effort required to achieve MEY, when based solely on prawn fishing, is 115–150 days per boat after accounting for fixed and variable fishing costs and annual fishing efficiency increases of 1–2%. From 2007–2014, the adjusted effort was 188–192 days per boat. Fishing occurred between March and November during 7–8 fishing periods, separated by 5–8 day (low catchability) moon closure periods. An empirical daily profit assessment (2007–2015), accounting for recruitment variation, daily prawn size compositions, monthly market prices for different prawn species and sizes, and daily fishing costs, showed vessels made profits on ~ 115–160 days and losses on ~ 15–55 days per year, when fishing occurred near the full moon. The fishery benefitted in 2013–2015 by starting later in the year and better targeting within-season effort. This management strategy within the effort-control framework, which improved profitability, maintained higher spawning stocks and reduced ecosystem fishing impacts, has wider application in prawn fishery management.     

东、黄海底拖网渔业渔捞努力量修正方法的探讨

渔捞努力量在渔业资源研究中是一个重要参数。在以往的东、黄海底拖网渔业资源研究中,投网次数常作为渔捞努力量的度量单位。在底拖网渔业中有很多影响渔捞努力量的因素,其中船型大小、实际捕捞时间的长短以及网具改进是主要因素。本文针对这三个因素应用上海市海洋渔业公司的资料,提出了一种修正方法,并对修正后标准渔捞努力量的效果进行了分析探讨。