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海龟放生装置在捕虾拖网上的应用 总被引:2,自引:0,他引:2
序言海龟是世界级保护的海洋动物,它的营养价值和经济价值都颇高。虾是海龟的主要饵料,因此,海龟一般栖息于虾渔场。由于最近几年来各国的拖网捕虾渔业迅速发展,拖网的捕捞强度不断提高,误捕海龟的事时有发生,致使海龟的数量日趋减少。为此。各国都在研究探索保护海龟的有效措施。联合国粮农组织规定各国的拖网捕虾船都必须使用保护海龟的海龟放生装置、以保护海电资源。本文介绍美国捕虾拖网船使用的海龟放生装置。1种类、结构及制造材料海龟放生装置分为坚硬型和软型两大类。目前、美国渔民使用的坚硬型有六种规格,其中使用最广、… 相似文献
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正本刊讯(隋然报道)1月14日,中国海龟保育学术交流会暨2019海龟增殖放流活动在广东海龟湾举办,旨在为国内外从事生态保护和海龟研究领域的专家学者搭建一个长久稳定交流的大平台。与会的专家学者就保护区管理,海龟保育、繁殖、救护等各个方面,提出了意见与建议,为今后的海龟保护事业提供科学、可靠的资料。 相似文献
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国际自然和自然资源保护同盟(IUCN)于今年2月向农业部渔政局、广东省南海海龟资源保护站和海南省渔政管理处等单位颁发了奖状,以表彰这些单位为保护中国海龟资源所做出的重要贡献。海龟是一种珍贵的海洋动物,在我国的广 相似文献
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海龟是世界级保护的海洋动物,它的营养价值和经济价值都颇高。虾是海龟的主要饵料,因此,海龟一般栖息于虾渔场。由于最近几年来,各国的拖网捕虾渔业迅速发展,拖网的捕捞强度不断提高,致使海龟的数量日趋减少,为此,各国都在研究探索保护海龟的有效措施。 相似文献
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9月19日下午,由农业部南海区渔政渔港监督管理局会同海南省海洋与渔业厅,海南省琼海市人民政府联合举办的“珍爱海龟、保护海洋”——2008年南沙保护海龟专项行动动员大会,在海南省琼海市潭门渔港举行,正式拉开了为期3个月的南沙保护海龟专项行动的帷幕。 相似文献
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本简要介绍了拉丁美洲的自然和人地理情况,分析了海龟种群资源及其栖息地的现状,叙述了海龟种群资源保护活动的发展历程,并提出了未来优先进行的海龟种群资源保护项目。 相似文献
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结合杭州市的实际,分析了养鳖业的发展趋势和现存在问题,提出增强竞争意识,改进养殖设施,提高科技含量,加强鳖病防治,推广鱼鳖混养,庭院养鳖,把握市场动态,加强精深加工,强化行业管理等发展对策。 相似文献
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Sarah M. Larocque Colin Lake Jonathan D. Midwood Vivian M. Nguyen Gabriel Blouin‐Demers Steven J. Cooke 《水产资源保护:海洋与淡水生态系统》2020,30(9):1783-1790
- Although it is sometimes difficult for researchers to ensure that their work is used by resource managers to make informed decisions, an example where this knowledge–action gap has been breached is in research published in Aquatic Conservation: Marine and Freshwater Ecosystems (AQC) – among other journals – that has assisted fisheries managers in identifying strategies for reducing freshwater turtle bycatch in commercial hoop net fisheries in Ontario, Canada.
- Research published in AQC has provided evidence towards a simple and effective method for preventing turtle bycatch mortality in hoop nets, which could be adopted by the fishers. Other research published in AQC evaluated the effect of bycatch mortality on the probability of persistence of turtle populations with population viability analyses, and outlined the need to minimize bycatch mortality to prevent local extirpation. Nine other papers have been published on freshwater turtle bycatch in Ontario, furthering our knowledge on this issue including seasonality and temperature effects on catches, other net modifications, post‐release effects and assisted recovery, and the perspectives of fishers.
- The research results were presented to local resource managers with further discussions involving industry and stakeholders to minimize turtle bycatch mortality. Over several years, researchers have provided information to resource managers; however, when an incident of high turtle mortality caught the public eye, the research was readily available and changes in regulations were quick to occur.
- Reasonably good communication among researchers, resource managers, industry, stakeholders, and the broader public allowed the rapid implementation of regulations to mitigate freshwater turtle bycatch mortality and bridged the knowledge–action gap between researchers and resource managers.
- Both articles published in AQC had practical conservation impacts and were influential in providing local resource managers with feasible solutions, and the impetus to change regulations. These impacts extended to other jurisdictions and their monitoring programmes, where methods to reduce turtle bycatch mortality were also implemented.
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中华鳖七群体体形和腹部黑斑图案的差异比较 总被引:3,自引:2,他引:3
对我国中华鳖代表性7个地方群体的成鳖阶段和后备亲鳖阶段的体形和腹部黑斑图案进行了,比较和分析。(1)把包括背甲周长、背甲宽、裙边后侧宽等16个参数转化为以背甲长为基数的15项比例性状进行多元函数分析。聚类分析表明,太湖鳖和崇明鳖较近,黄河鳖和淮河鳖较近,洞庭湖鳖和鄱阳湖鳖较近。主成份分析表明,把7群体一起分析的绘图,相互覆盖较多,不易分清:若是取3个群体,如对黄河鳖、洞庭湖鳖及太湖鳖分析绘图,则趋同性和趋异性十分清楚。判别分析表明,7群体的判别准确率在44%~73%之间,黄河鳖群体的判别准确率最高;(2)裙边宽厚度是中华鳖的重要经济指标。黄河鳖、淮河鳖及洞庭湖鳖的裙边均较宽而厚,其裙边后侧宽/背甲长之比超过7群体总平均值1~4.6个百分点;(3)中华鳖体色存在群体间固有的差异。首先表现在腹部的黑色斑块的有无和多少上,在后备亲鳖阶段,黄河鳖腹部全白的比例达100%,洞庭湖鳖和鄱阳湖鳖及淮河鳖腹部全白的比例在80%~90%;太湖鳖、崇明鳖及台湾鳖腹部全白的比例仅12%~22%。其次表现在腹部黑色斑块的出现频率和黑色程度有从黄、淮河流域和长江中游水域向长江下游水域及台湾增高、增强的明显趋势。黄河鳖、淮河鳖、洞庭湖鳖及鄱阳湖鳖是为“玉鳖”群,太湖鳖、崇明鳖及台湾鳖是为“花鳖”群。中华鳖腹部黑色斑块图案,是既受遗传控制,也受环境影响,还受遗传-环境相互作用的复杂表型。 相似文献
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Reducing sea turtle by-catch in pelagic longline fisheries 总被引:6,自引:0,他引:6
Eric Gilman Erika Zollett Stephen Beverly Hideki Nakano Kimberly Davis Daisuke Shiode Paul Dalzell & Irene Kinan 《Fish and Fisheries》2006,7(1):2-23
Reducing by‐catch of sea turtles in pelagic longline fisheries, in concert with activities to reduce other anthropogenic sources of mortality, may contribute to the recovery of marine turtle populations. Here, we review research on strategies to reduce sea turtle by‐catch. Due to the state of management regimes in most longline fisheries, strategies to reduce turtle interactions must not only be effective but also must be commercially viable. Because most research has been initiated only recently, many results are not yet peer‐reviewed, published or readily accessible. Moreover, most experiments have small sample sizes and have been conducted over only a few seasons in a small number of fisheries; many study designs preclude drawing conclusions about the independent effect of single factors on turtle by‐catch and target catch rates; and few studies consider effects on other by‐catch species. In the US North Atlantic longline swordfish fishery, 4.9‐cm wide circle hooks with fish bait significantly reduced sea turtle by‐catch rates and the proportion of hard‐shell turtles that swallowed hooks vs. being hooked in the mouth compared to 4.0‐cm wide J hooks with squid bait without compromising commercial viability for some target species. But these large circle hooks might not be effective or economically viable in other longline fisheries. The effectiveness and commercial viability of a turtle avoidance strategy may be fishery‐specific, depending on the size and species of turtles and target fish and other differences between fleets. Testing of turtle avoidance methods in individual fleets may therefore be necessary. It is a priority to conduct trials in longline fleets that set gear shallow, those overlapping the most threatened turtle populations and fleets overlapping high densities of turtles such as those fishing near breeding colonies. In addition to trials using large 4.9‐cm wide circle hooks in place of smaller J and Japan tuna hooks, other fishing strategies are under assessment. These include: (i) using small circle hooks (≤ 4.6‐cm narrowest width) in place of smaller J and Japan tuna hooks; (ii) setting gear below turtle‐abundant depths; (iii) single hooking fish bait vs. multiple hook threading; (iv) reducing gear soak time and retrieval during daytime; and (v) avoiding by‐catch hotspots through fleet communication programmes and area and seasonal closures. 相似文献
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中华鳖爱德华菌病病原菌的分离鉴定及致病因子研究 总被引:1,自引:0,他引:1
采用API 20E系列生化鉴定及16S rDNA和gyrB基因序列同源性分析方法,对从患病中华鳖(Trionyx sinen-sis)肝脏中分离到的一株细菌TL5m进行了鉴定,并通过人工感染试验,对该菌株进行了毒力检测;此外分别提取该TL5m株的主要致病因子外膜蛋白、脂多糖和胞外产物,对中华鳖进行毒力和免疫保护率试验。结果显示:菌株TL5m的API 20E鉴定编码为4544000,99.9%为迟钝爱德华氏菌(Edwardsiella tarda);其16SrDNA序列和gyrB基因序列(GenBank登录号分别:EF121756和GU563803)与迟钝爱德华氏菌的同源性最高(分别为94%和98%);菌株TL5m对中华鳖的半数致死量LD50为2.45×106 CFU/ind。药敏感结果显示菌株对磷霉素、菌必治、头孢孟多、头孢噻吩、壮观霉素高度敏感。外膜蛋白攻毒剂量60μg/ind和脂多糖攻毒剂量400μg/ind时,对中华鳖的致死率都为33.3%,胞外产物对中华鳖的LD50为31.73μg/ind;全菌灭活苗、胞外产物、外膜蛋白和脂多糖的免疫保护率分别为75%、62.5%、25%和87.5%。结果表明,发病中华鳖的病原菌为迟钝爱德华氏菌,其分泌的胞外产物对中华鳖具有较高毒力;提取的脂多糖对中华鳖遭受迟钝爱德华氏菌攻击具有较高免疫保护率。 相似文献
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对1996年底发生在我国东南部沿海地区温室养鳖场原因不明、症状复杂的鳖病进行了寄生虫学、细菌学和病毒学检验,结果未获得致病性病原生物。结合流行病学调查、组织病理和病理生理学检验结果证实,肝脏的病理变化严重,并有规律性,肝功能由功能不全到功能衰竭。临床症状早期表现不明显,晚期严重肝淤血、肝血肿、肝硬变并出现全身性水肿。诊断为中华鳖非寄生性肝病(non-parasiticalyhepatitisofChinesesoft-sheledturtle)。该病为严重肝损害所致,病因为药物、毒物和强化投饲等综合因素。该病患病率高、危害性大,要早期诊断,及时预防与治疗。 相似文献
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- 1. The threatened status of many sea turtle populations and their vulnerability to coastal development and predicted climate change emphasize the importance of understanding the role of environmental factors in their distribution and ecological processes. The factors driving the distribution of sea turtle nesting sites at a broad spatial scale is poorly understood.
- 2. In light of the lack of understanding about physical factors that drive the distribution of turtle nesting, the relationship between nesting site distribution and the exposure of coastal areas to wind and wind‐generated waves was analysed. To achieve this, a Relative Exposure Index (REI) was developed for an extensive area in north‐eastern Australia and values of the index for nesting sites of five different sea turtle species and randomly selected non‐nesting sites were compared.
- 3. Although there are differences between species, the results show that sea turtles nest in areas of higher REI values suggesting that wind exposure is related to the spatial distribution of sea turtle nesting sites, and it may also influence nest site selection in female turtles and/or the dispersal of hatchlings towards oceanic currents.
- 4. The combination of these results with further research on other driving environmental factors, like oceanic currents, has the potential to allow for the identification and prediction of future nesting sites, for which conservation and management may become essential. Copyright © 2009 John Wiley & Sons, Ltd.
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Reconstructing 290 years of a data‐poor fishery through ethnographic and archival research: The East Pacific green turtle (Chelonia mydas) in Baja California,Mexico 下载免费PDF全文
Michelle‐María Early‐Capistrán Andrea Sáenz‐Arroyo José‐Gilberto Cardoso‐Mohedano Gerardo Garibay‐Melo Volker Koch 《Fish and Fisheries》2018,19(1):57-77
Evaluating historical changes in the exploitation of marine organisms is a key challenge in fisheries ecology and marine conservation. In the Eastern Pacific, marine turtles were exploited for millennia before systematic monitoring began <50 years ago. Using ethnographic and historical data, we generated a detailed reconstruction of the East Pacific green sea turtle (Chelonia mydas) fishery in Mexico's Baja California peninsula from 1700 to 1990. Sea turtles from the region's important feeding areas were a staple food source from the earliest phases of human occupation, dating back at least 12,000 years. In contrast with regions such as the Caribbean, small human populations and limited market access resulted in apparently sustainable turtle harvests until the second half of the 20th century. We found that the estimated annual catches between 1960 and 1980 exceeded the estimated annual catches of the previous 250 years by an order of magnitude, leading to the collapse of the fishery and the depletion of the green turtle population. A total ban on sea turtle captures in 1990, comprehensive nesting beach protection, and significant conservation efforts resulted in increases in breeding females on nesting beaches and catch rates in scientific monitoring on main feeding grounds since the early 2000s. This provides a positive outlook for this once‐depleted population segment. Although further research is needed to evaluate current conservation status, we have identified a date, between 1950 and 1960, which can serve as a reliable temporal reference for future evaluations of historical baseline abundance in this region. 相似文献