Quantification of the invasiveness risk of non-native macroalgae in the Azores to support conservation measures

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有关长江流域鱼类资源保护的几个问题

为了确定监测时长、监测网具、站位布局对禁捕后长江鱼类资源监测评估的有效性,于2021年5—7月在长江中游10个站位开展了鱼类资源捕捞监测,每个站位连续监测15 d,从日捕获量、物种记录数、渔获物群落结构等3方面着手,对监测时长、监测网具、站位布局等的设置进行探讨。结果显示,连续11 d捕捞监测所得累计日均渔获量基本达到稳定,连续15 d捕捞监测可以记录到站位近70%的鱼类种类数,所得累计鱼类群落结构基本达到稳定。网具类型、规格的使用覆盖对监测结果中鱼类种类记录数、鱼类群落结构有明显影响,网具使用量对监测结果中日均渔获量有明显影响。10个监测站位间的鱼类群落结构具有明显差异,结合监测站位间的空间距离来看,鱼类群落结构具有较高的空间异质性。研究表明,为了保障评估结果的准确性,基于原始监测数据进行相关评估之前,有必要对监测数据的充分性、有效性进行检验,网具类型、规格和使用量对监测结果的影响应予以适当考虑,各具体江段的鱼类群落结构评估应由相应具体江段的监测结果来支撑。本研究将为长江流域重点水域全面禁捕后的水生生物资源监测评估提供科学支撑。     

长江流域鱼类资源现状与保护对策

为科学评价长江十年禁渔政策在金沙江下游水库的初步实施效果,实验于2020年11月和2022年5月在金沙江下游向家坝水库开展了渔获物调查和水声学调查,并分析了鱼类资源的变化情况。渔获物调查结果显示,2020年11月共采集到鱼类2科9种,其中䱗、瓦氏黄颡鱼占优势地位;2022年5月共采集到鱼类5科14种,其中蛇、瓦氏黄颡鱼占优势地位。水声学调查结果显示,不同年间、不同区域、不同水层间的鱼类目标强度分布存在显著性差异;2022年5月的鱼类密度 (0.60 尾/1 000 m³)高于2020年11月 (0.46 尾/1 000 m³),鱼类资源在时空分布上呈现不均匀性;不同调查时期的鱼群密集区域存在一定的差异,2020年11月大部分区域之间差异不显著,2022年5月则差异显著;2022年5月的上层鱼类密度 (0.44±0.83 尾/1 000 m³)显著大于2020年11月 (0.06±0.15 尾/1 000 m³);不同水层的鱼类分布差异显著,2次调查均表现为下层大于中、上层;估算得到向家坝水库鱼类资源尾数分别为3.22×10⁶ 尾 (2020年11月) 和3.53×10⁶ 尾 (2022年5月)。综上所述,水声学调查方法适用于金沙江下游水库的鱼类资源监测工作,十年禁渔实施后向家坝库区鱼类资源已得到一定程度的恢复。     

Historical spatial baselines in conservation and management of marine resources

Increased knowledge on the spatial distribution of marine resources is crucial for the implementation of a true ecosystem approach to management and the conservation of marine organisms. For exploited fish species characterized by aggregation behaviour during spawning time, the identification and tracking of spawning areas is essential for a correct assessment of their productivity and population abundance. To elucidate this concept, we reconstructed the spatio‐temporal distribution of adult plaice (Pleuronectes platessa, Pleuronectidae) during spawning time along the 20^th century. Historical data reveal that not only the abundance but also the former population richness was much higher than previously estimated and has declined because of protracted over‐exploitation during the last 30 years. We conclude that forecast of stock recovery to former levels of abundance neglecting spatial reorganizations might be over‐optimistic and shaded by a lost memory of the past population richness. These results reinforce the importance of managing exploited marine resources at a greater spatial resolution than has been carried out in the history of fishery management.     

浅谈黄壁庄水库渔业资源保护现状、问题及对策

分析了黄壁庄水库渔业资源现状及存在问题,对今后如何恢复和保护该水库渔业资源提出了对策建议.     

Wintering seaducks in Britian and Ireland: Populations,threats, conservation and research priorities

• 1. This paper provides a detailed review of the status and distribution of wintering seaducks (Scaup, Eider, Long-tailed Duck, Common Scoter, Velvet Scoter and Red-breasted Merganser) in Britain and Ireland. It is based on a literature review plus analysis of National Waterfowl Counts (NWC) and other data. A summary of current knowledge of wintering seaducks is provided together with information on threats to populations, conservation goals and research needs.
• 2. Each species is examined in turn, with the emphasis on aspects of the population, habitat use, current distribution, trends and history. Important areas for individual species are highlighted.
• 3. Overall, seaduck populations have changed considerably, those for Eider and Red-breasted Merganser having expanded greatly, whilst those for Scaup, Common and Velvet Scoter have declined during historical and/or recent times. The trend for Long-tailed Ducks is unclear. British population estimates are considered to be out of date and need to be revised. The premier areas for seaduck communities are highlighted, thus providing basic information for conservation action and future monitoring.
• 4. Seaduck populations are threatened in a number of ways and the main factors are discussed. Oil pollution and the actions of commercial fisheries are the most important current threats. Conservation goals are suggested. These include an urgent need to develop appropriate domestic legislation to facilitate the protection of seaduck populations. Such legislation is currently almost entirely lacking.
• 5. Some priorities for research, particularly for better population monitoring of seaducks in British and Irish waters, are provided. These include: alterations to the NWC scheme to allow the collation of opportunistic counts, made when the conditions are amenable for censusing seaducks; extension of the scheme into areas not currently surveyed (e.g. most parts of Ireland); and the establishment of intensive survey programmes to monitor seaducks in the key areas of Britain and Ireland. It is hoped that this paper will serve to stimulate interest and commitment from all who play a part in safeguarding our seaduck heritage.

     

Marine conservation planning in practice: lessons learned from the Gulf of California

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Minimal overlap between areas of high conservation priority for endangered Galapagos pinnipeds and the conservation zone of the Galapagos Marine Reserve

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海龟资源保护及其疾病的研究进展

本文就海龟的种属、流行病学及各国采取的一系列对海龟的保护措施进行介绍.重点综述了海龟常见疾病的诊断技术和治疗方法,更深入地探讨了海龟组织病理学、病原学研究方面的进展,为海龟保护计划提供了重要的理论参考.     

Implications of recreational fishing for elasmobranch conservation in the Great Barrier Reef Marine Park

• 1. 309 Great Barrier Reef Marine Park recreational fishers were surveyed to examine recreational catch and harvest of elasmobranchs and to explore recreational fishers' handling behaviour and attitudes.
• 2. Elasmobranchs represented 6% of fishers' total catch of all fish (including released individuals), and 0.8% of fishers' total harvest (i.e. retained individuals) across all survey days. The majority of elasmobranchs caught by fishers were released, primarily because they were perceived as being inedible.
• 3. Recreational fishers' self‐reported handling and release behaviour for elasmobranchs is largely consistent with ‘best practice’ guidelines except that fishers had low use of circle hooks and barbless hooks, and a significant proportion (33%) reported using stainless steel hooks.
• 4. Most fishers had positive attitudes towards elasmobranchs, placing high importance on releasing sharks and rays in good condition (86%), high value on their existence (84%), and low value on catching them (63%).
• 5. Results indicate that post‐release mortality is probably the largest source of recreational fishing mortality of elasmobranchs in the Great Barrier Reef. Future research should be targeted at obtaining better estimates of species‐specific post‐release mortality levels, understanding how post‐release survival can be increased by changing fishing techniques or fisher behaviour, and developing more effective methods of engaging fishers in elasmobranch conservation. Copyright © 2009 John Wiley & Sons, Ltd.

     

Emerging frontiers in perceptions research for aquatic conservation

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Fish genetics and conservation research in India: status and perspectives

Recent years have witnessed a rise in sensitivity towards protection of natural genetic resources and the environment at the international level. This is evident from the implementation of the convention on biodiversity (CBD). To conserve and optimize utilization of its bioresources, India enacted the Biological Diversity Act 2002. The conservation and management of aquatic resources is important for sustainable utilization of fisheries potential for the economic advancement of farmers and fishery workers, today as well as for posterity. As the biotechnological and genomic revolutions are ready to take off, the sovereign rights of native inhabitants to intellectual property rights (IPR) related to aquatic genetic resources and associated traditional knowledge are also integral components of management strategies for genetic resources.     

唐山祥云湾海洋牧场渔业资源增殖效果评估

为评估唐山祥云湾海洋牧场渔业资源的增殖效果,对其投礁前后生物资源进行调查,选取主要经济渔获物为统计对象,结果表明:投礁后主要经济渔获物的生物总量是投礁前的2.5倍,Pileou均匀度指数(J′)是投礁前的1.82倍,Shannon-Weiner多样性指数(H′)是投礁前的2.14倍,种类丰富度指数(R)是投礁前的1.9...     

鱼类两性嵌合体及其在种质保存中的应用前景

本文对鱼类两性嵌合体的概念、产生以及在科研和生产上的意义作一综述,并首次提出鱼类两性嵌合体在鱼类种质资源保存中的应用价值。两性嵌合体（ａｍｐｈｉｇｅｎｅｔｉｃｍｏｓａｉｃｓ）是指在组织学成分中同时混杂存在着雌雄两类生殖细胞的生殖腺（性腺）,是鱼类中一类特殊的生殖腺。两性嵌合体根据其中两类生殖细胞数量的相对比例以及特定的遗传和生理条件,有的是不育的（即不能产生具有受精能力的精子或卵子）,有的是能育的（如正常排卵受精）;有的两性嵌合体则是性转变过程中的中间过渡形式。判别鱼类的一种生殖腺是不是两性嵌合…     

Extent and possible conservation implications of fish use for research,testing and education in North America

• 1. Fish species are used globally for fundamental research, product and environmental testing, and education, but this use has not hitherto been documented. The number of fish used for research and education in North America currently represents approximately one‐quarter of all animal use for these purposes; only mice are used in higher numbers. Data from the Canadian Council on Animal Care, various animal care committees from Canadian universities, and the United States Fish and Wildlife Service are collated and summarized.
• 2. In Canada nearly a half a million fish were used for research and education each year from 1996 to 2001. We estimated that the United States used over four times that amount for the same purposes, totalling approximately 2.8 million fish each year.
• 3. At least 100 fish species, representing 27 taxonomic orders, were used for research and education in North America from 1996 to 2001. Close to one‐third of the species had life‐history characteristics that might make them particularly susceptible to over‐exploitation. This potential vulnerability, coupled with data from animal care facilities in Canada suggesting that nearly half of all fish used for research and education were wild‐caught, should prompt further documentation of such fish uses in order to assess their sustainability.

Copyright © 2006 John Wiley & Sons, Ltd.