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101.
The behavioural dynamics of fishers: management implications   总被引:4,自引:0,他引:4  
In pursuing their livelihood, fishers develop strategies when faced with changes in regulations and other fishery conditions. Changes involve each individual in a decision‐making process governed by his/her own goals or constraints. Despite this reality, the complex dynamics of fishing has usually been ignored in designing management initiatives, which has contributed to management failures in many parts of the world. Fishers have generally been treated as fixed elements, with no consideration of individual attitudes based on their operating scales (geographical, ecological, social and economic) and personal goals. We review existing research on the social, economic and behavioural dynamics of fishing to provide insight into fisher behaviour and its implications for fisheries management. Emphasis is placed on fisher perception, and how fishers develop dynamic fishing tactics and strategies as an adaptive response to changes in resource abundance, environmental conditions and market or regulatory constraints. We conclude that knowledge of these dynamics is essential for effective management, and we discuss how such information can be collected, analysed and integrated into fisheries assessment and management. Particular emphasis is placed on small‐scale fisheries, but some examples from industrial fleets are provided to highlight similar issues in different types of fisheries.  相似文献   
102.
王鲁民  王忠秋 《水产学报》2023,36(11):119716-1-119716-11
综合应用船舶、机械、信息、新材料等技术,从海洋中捕捞经济渔获物并综合利用,是现代海洋捕捞业的主要特征。海洋捕捞技术的发展和创新,对保障我国食物安全、保护近海生态与资源、实现渔民增收和新渔村建设、推动渔业产业结构调整和转型、维护我国海洋权益等方面具有非常重要的作用。本文通过简析海洋捕捞渔场探测、渔具渔法与高效自动化辅渔助渔技术等方面的研究进展,提出海洋捕捞技术的重点发展方向,以期为我国海洋捕捞实现节能高效、生态友好和资源可持续利用,海洋捕捞技术升级和产业高质量发展提供参考。  相似文献   
103.
    
  1. With the increasing popularity of recreational angling around the world, there is a need to better understand the potential contribution of recreational fishing to reported shark population declines. However, the nature and perception of shark encounters – a fundamental precursor to future research, management and conservation measures aimed to increase shark survival – is not well documented in recreational fisheries.
  2. Five hundred and ninety recreational saltwater anglers responded to the survey and reported their experiences targeting or incidentally catching sharks, as well as their attitudes toward sharks, shark fishing techniques, and shark conservation and management.
  3. The survey found sharks were caught regularly, with 57% of respondents commonly targeting sharks and 93% of respondents having caught a shark at least once. Eighty‐eight percent of the respondents released the last shark that they caught and most respondents often or always practised catch‐and‐release when catching sharks.
  4. The survey revealed that avid anglers have positive attitudes toward sharks and shark conservation and have a desire to handle and release sharks in ways that will increase their likelihood of survival.
  5. However, the survey also revealed that there are a variety of situational factors (e.g. target fish, fishing platform) that influence the choices that anglers make while fishing, which may influence adherence to catch‐and‐release methods.
  6. Based on their positive attitudes toward sharks, recreational anglers may be strong allies for the development, dissemination, and adoption of species and situational‐specific best practice catch‐and‐release guidelines for this group of fishes within the wider recreational saltwater angling community.
Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
104.
The mandarinfish, Synchiropus splendidus, is a small, pelagic-spawning enthic dragonet of the western Pacific. Although popular in the marine aquarium trade, little is known of its fishery or biology. All aquarium-trade animals are currently taken from the wild and the impact of heavy collecting is unknown. The specialized and selective nature of the fishery for mandarinfish is described and its potential to disrupt the mating system identified. As a possible alternative to wild capture and as an aid to sustainable exploitation, egg production and early development relevant to mariculture are described, including egg output, embryo, larva and post-settlement development to 30 days, based on live material. Egg output was determined for 40 females and ranged from 12 to 205 eggs. Embryo and larva development were rapid, with settlement occurring within 14 days at 24–26 °C, and at 3.5 mm TL. The swimbladder is retained in adults. Our limited attempts at raising the mandarinfish to settlement were encouraging and suggest an excellent potential for mariculture with implications for both conservation and improved maintenance of fish in captivity. At present, given that this species is difficult to maintain in captivity, it is only suitable for experienced aquarists. Preliminary diet information is provided. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
105.
本文叙述了采用 8种网线复捻捻回角的超高分子量聚乙烯渔网线强力性能的试验结果。经分析可见 ,网线的断裂强力、单线结强力均与捻回角的余弦呈回归关系。以网线的断裂强力性能为主 ,兼顾网线的单线结强力、断裂伸长率等性能参数 ,比较UHMWPE、普通聚乙烯和聚酰胺三种纤维制成网线后 ,它们的强力利用率均应 >6 5 % ,由此得出制作超高分子量聚乙烯渔网线合理的捻回角区间为 18°~ 2 1°  相似文献   
106.
以海洋模式物种一海水青鳉(Oryzias melastigma)为研究对象,设置了90%大个体捕捞(H-B)、90%随机捕捞(H-R)、75%大个体捕捞(M-B)、75%随机捕捞(M-R)、50%大个体捕捞(L-B)、50%随机捕捞(L-R)、75%小个体捕捞(M-S)7种捕捞策略处理组,用以研究海水青鳉的生长特征在不...  相似文献   
107.
渔用浮标定位监视系统   总被引:1,自引:0,他引:1  
介绍了几种常用的渔用浮标定位监视系统的基本组成、工作原理及各自的特点。着重对GPS渔用浮标定位监视系统的模式及各组成部分的功能和设计的关键技术进行了讨论。采取适当方法解决关键技术后,使GPS渔用浮标定位系统具有较强的抗干扰能力和信息自动交换能力,特别适合在海洋中容易漂移的渔具、航行器等设备中作位置监视、搜寻之用。  相似文献   
108.
大眼金枪鱼和黄鳍金枪鱼是印度洋金枪鱼延绳钓的主要渔获种类.通过计算以渔获量为权重的经度和纬度的加权平均值即渔场重心和利用空间距离分析方法,分别对1967-1987年、1988-2004年两个时间段的印度洋大眼金枪鱼、黄鳍金枪鱼延绳钓渔场重心的年内、年际变化规律和各月渔场重心空间聚类情况进行研究.研究表明,渔场重心在年内呈现出规律性变化,大眼金枪鱼月重心变化1-4月向西北移动,5-8月向东南方向移动,9-12月向东北方向移动;黄鳍金枪鱼月渔场重心变化1月向西北移动,2-4月向西移动,5-8月份向东南移动,9-12月份向东北移动,这在一定程度上反映了印度洋大眼金枪鱼、黄鳍金枪鱼的洄游规律.渔场重心的年间变化受到了海洋环境条件变化所引起的南方涛动现象(ENSO)的影响,大部分发生El Nio的当年或次年,年渔获量分布重心会向南、向西移;发生La Nia的年份前后渔获量分布重心会向北、向东移.同时捕捞行为也对渔场重心的年间变化产生影响.  相似文献   
109.
选择全国7个主栽小麦品种,通过培养试验研究了外源添加硒酸盐以及亚硒酸盐对小麦的生物毒害作用,旨在确定小麦发芽阶段硒敏感指标并且为耐硒小麦品种的筛选提供依据。结果表明:添加低浓度外源硒(硒酸盐<8 mg·L-1,亚硒酸盐<20 mg·L-1)能够促进发芽阶段小麦的生长,高浓度硒(硒酸盐≥8 mg·L-1,亚硒酸盐≥20 mg·L-1)则表现为显著的抑制作用;同等硒浓度条件下(10 mg·L-1),硒酸盐对小麦种子的毒害作用显著高于亚硒酸盐(P<0.05)。指标综合相关性模型与Bartlett球形检验结果表明  相似文献   
110.
基于贝叶斯概率的印度洋大眼金枪鱼渔场预报   总被引:1,自引:0,他引:1  
本文采用贝叶斯概率为模型基础框架,利用来自印度洋金枪鱼管理委员会(IOTC)的大眼金枪鱼延绳钓历史渔获统计数据和美国国家海洋大气管理局(NOAA)的海温最优插值再分析数据,进行适用于印度洋金枪鱼延绳钓渔场的模型参数估算与预报模型构建。模型回报精度验证结果表明,印度洋大眼金枪鱼延绳钓渔场综合预报的准确率达到了65.96%。模型预报结果用概率百分比来表示,符合渔业资源分布的客观特点。利用中分辨率成像光谱仪MODIS提供的SST产品进行业务化运行的渔场预报,利用模型结果每周生成印度洋大眼金枪鱼延绳钓渔场概率预报图,用不同大小的圆形来表示渔场概率的高低,可以为印度洋区域的远洋渔业生产提供信息支持。  相似文献   
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