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灯光罩网是南海外海的一种主要捕捞方式, 夜晚作业时点斑原海豚(Stenella attenuata)常常聚集在渔船周围进行捕食活动, 导致被网具兼捕死亡。本研究研发宽带声波驱豚系统, 分别于 2019 年 5 月 19 日和 28 日在南海进行海上试验, 确定了驱赶点斑原海豚的有效频段, 定量评估了驱豚效果。研究结果表明: 1~10 kHz 的线性调频信号对点斑原海豚有一定的驱赶作用。2 次试验系统开启前的海豚单体信号数目小于开启后, 而离船平均间距大于开启后, 即海豚远离了调查船; 5 月 28 日试验时, 系统开启后 3 个阈值均没有检测到疑似单体信号, 即在离船 120 m 范围内, 无点斑原海豚存在。系统开启前后 20 min, 垂直声学映像中各单元格的平均 NASC 值存在显著性差异 (P<0.05), 且开启前的 NASC 要小于开启后。通过海上试验, 本研究验证了宽带声波驱豚系统的有效性, 初步确定了驱赶点斑原海豚的有效声波频段与脉冲模式, 然而本研究还有一些不足之处, 需要进行更多的试验予以完善, 以便于未来的推广应用。 相似文献
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以洞庭湖和原种场长吻（Leiocassis longirostris）为研究对象,采用20个随机引物对10个野生个体进行了随机扩增多态性DNA（random amplified polymorphic DNA,RAPD）群体遗传多样性分析。共检测到103条带,每个引物产生的条带数在2～9之间,片段大小在0.2～3.0kb之间,多态座位比例为41.75%,2群体内个体间遗传相似系数和遗传距离分别是,洞庭湖个体间遗传相似性系数（S）0.8795～0.9833,遗传距离（D）0.0167～0.1205;原种场个体间S为0.8794～0.9892,D为0.0319～0.1108;比较2群体S为0.7983～0.9994,D为0.0167～0.3017;Nei遗传多样性指数（He）0.3269。结果表明,长吻群体内遗传多样性较为丰富。 相似文献
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利用2012—2019年中国金枪鱼延绳钓渔业观察员计划获取的数据,采用α多样性指标分析了中东太平洋海域鲨鱼的物种多样性,并利用广义加性模型分析了其栖息地偏好。结果表明,中东太平洋金枪鱼延绳钓渔业兼捕鲨鱼共20种,主要种类为大青鲨(Prionace glauca)和镰状真鲨(Carcharhinus falciformis)。中东热带太平洋和东南太平洋海域的鲨鱼物种组成相似,但中东热带太平洋鲨鱼物种均匀度更高,且热带海域的鲨鱼生物多样性高于温带地区。鲨鱼的物种丰富度和Shannon多样性指数受栖息地环境影响,存在较大的时空差异。鲨鱼群落更倾向于栖息在具有较高生产力水平(叶绿素浓度0.10 mg·m~(-3))和海平面距平偏低(海平面距平值0 m)的温水(海表面温度25℃)海域。研究利用α多样性指数识别了以中东太平洋赤道水域(10°N～5°S、110°W～130°W)为主的鲨鱼物种多样性热点区域,有助于了解大洋生态系统鲨鱼物种多样性的时空分布特征,为制定针对鲨鱼的养护管理措施提供科学参考。 相似文献
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《水产科学》2021,(4)
为提高罗非鱼链球菌病发前的早期预警,根据海豚链球菌的16S rRNA基因的部分序列和无乳链球菌的Sip基因特异性序列,分别合成特异性检测引物,经过对反应体系和反应条件的优化,建立检测较低含量的无乳链球菌和海豚链球菌的分子技术。试验结果显示,所建立的双重PCR可扩增出870 bp无乳链球菌和614 bp海豚链球菌的特异性片段,而迟钝爱德华氏菌、维氏气单胞菌、创伤弧菌、温和气单胞菌、溶藻弧菌、大肠杆菌均为阴性;无乳链球菌和海豚链球菌基因组DNA最低检测量分别为9.84×10~(-5) ng/μL和9.30×10~(-5) ng/μL,菌液最低检测量分别为2.76×10~3 cfu/mL和2.51×10~3 cfu/mL,远低于其半致死密度10~7 cfu/mL;对无乳链球菌和海豚链球菌混合感染的模拟临床样品的检出率为100%。研究结果表明,该分子技术的特异性较强、灵敏度较高、检出率较高,可用于较低含量的无乳链球菌和海豚链球菌的快速鉴别,为罗非鱼链球菌的早期预警分子检测提供技术支持。 相似文献
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通过核基因ITS2片段研究四种鲇形目鱼类进化 总被引：5，自引：0，他引：5
采用鲇形目鱼鱼类通用引物扩增了鲇形目鱼类4种鱼,长吻(Leiocassi longirostris)、南方南方大口鲇(Si-lurus meridionalis)、黄颡鱼(Pseudobagrus fulvidraco)、斑点叉尾(Ictalurus punctatus)核DNA的ITS2片段,并构建UPMGA,NJ,ME和MP系统树。结果显示:根据遗传距离,斑点叉尾和黄颡鱼的亲缘关系最近(D=0.0661),接下来是黄颡鱼和南方大口鲇(D=0.1100),南方大口鲇和长吻(D=0.1184),斑点叉尾和南方大口鲇(D=0.1266),黄颡鱼和长吻(D=0.1490),斑点叉尾和长吻的亲缘关系是最远的(D=0.1503)。结果表明:长吻最早分化,其次是南方南方大口鲇和黄颡鱼,而斑点叉尾分化最晚。 相似文献
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采用RAPD技术从30个随机引物中筛选出20个引物对洞庭湖区野生长吻鮠群体的遗传多样性进行研究,结果共检测出105个位点,其中54个(51.43%)呈多态;利用POPGEN软件获得野生长吻鮠群体10个个体间的遗传距离,个体间遗传距离(D)在0.1685~0.6425,个体间遗传相似系数(S)在0.3575~0.8315。通过与其他鱼类的遗传多样性的研究结果比较可初步判断,洞庭湖区野生长吻鮠群体的遗传多样性较低。由于没有以前的遗传多样性分析资料,因此不能评判过度捕捞和自然环境的破坏等因素对长吻鮠遗传多样性的影响程度。 相似文献
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鱼类环境DNA研究中通用引物的筛选验证 总被引：2，自引：0，他引：2
为了筛选一个通用性和适用性良好的能够运用于环境DNA(eDNA)研究的鱼类引物,从相关文献中选取了鱼类线粒体基因组部分片段的5对引物,分别对线粒体D-loop区、16S rRNA基因、COI基因以及Cytb基因部分片段进行扩增。对千岛湖48种鱼类基因组DNA进行扩增后比较发现,引物16s和COI均可以取得良好的扩增效果,通用性优于其他几对引物。引物16s的扩增产物经凝胶电泳检测均出现明亮的目的条带,引物COI则有3种鱼的条带经凝胶电泳检测亮度较暗。利用上述引物对环境样品eDNA扩增时发现,只有16s和COI的引物具有良好的扩增效果,能够得到明显单一的亮带。对该两种引物的PCR产物克隆后测序比对发现,16s的PCR产物均为千岛湖常见鱼类物种的基因片段,COI的PCR产物则为细菌COI基因的部分片段。综上,我们认为引物16s在通用性和适用性上都更为适合作为鱼类群落结构eDNA研究的通用引物。 相似文献
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DNA条形码基因已经广泛应用在海洋贝类的分类鉴定、系统发育进化、种群遗传分析等领域的研究。为进一步研究评估不同DNA条形码基因在海洋贝类鉴定中的作用,本研究利用从Gen Bank数据库随机下载的帘蛤目COI、16S r RNA、18S r RNA和28S r RNA基因序列,通过传统距离法和单系聚类法结合分析,比较了上述DNA条形码基因在鉴定物种及系统发育进化中的鉴定效率,并以本实验室已获得的部分贝类DNA序列进行了验证。结果表明,根据"10倍法则"和"2%"阈值标准,本研究中COI能够鉴定57.1%物种,16S r RNA能够鉴定60.9%,18S r RNA鉴定16.7%,而28S r RNA无法有效鉴定;多数种COI和16S r RNA基因序列的种间遗传距离和种内遗传距离存在"条形码间隙",而18S r RNA和28S r RNA序列的种间和种内的遗传距离存在显著重叠,没有明显"条形码间隙";聚类分析结果表明,基于COI基因序列,87.9%的个体与同种聚为单系,以16S r RNA序列,65.6%的个体与同种聚为单系,未聚成单系的个体则形成姐妹系,未出现不同种聚为单系现象,能够呈现与形态分类基本一致的系统发生关系;但18S r RNA和28S r RNA呈现的聚类关系相对混乱。相对而言,在鉴定帘蛤目物种时,COI和16S r RNA都能够作为条形码基因,且COI有效性更高,18S r RNA和28S r RNA基因由于种内变异较大,不适于作为条码基因。研究结果为科学选用DNA条形码基因进行帘蛤目贝类的鉴定提供了参考资料。 相似文献
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Cristina B. Milani Adriana Vella Pavlos Vidoris Aristidis Christidis Nikolaos Kamidis Eygenia Leykaditou 《Fisheries Management and Ecology》2019,26(4):374-388
Greek fisheries (purse seine, trawling and small‐scale coastal, by order of importance) mostly operate in the Thracian Sea, which despite its relatively small size relative to the Aegean Sea (≈4.4%) is the most productive region in Greek waters due to its elevated nutrient concentration. The Thracian Sea is also vital to several species of cetaceans, mainly bottlenose dolphin, Tursiops truncatus (Montagu), and common dolphin, Delphinus delphis L. The area has been proposed as a potential cetacean conservation hotspot. For this reason, the interactions between fishing activities and local cetacean populations have been investigated through reports of stranded dolphins, interviews with fishers, surveys and detailed dolphin stomach content analysis. Reports of stranded cetaceans and interviews with fishers revealed cases of cetacean entanglement in fishing nets, as well as frequent dolphin damage to fishing nets. Necropsy stomach analysis of stranded dolphins revealed a preference for fish and cephalopods of low commercial value, indicating a low trophic overlap between cetaceans and commercial fisheries. Recommendations for the management of fisheries–cetacean interactions in the Thracian Sea are provided. 相似文献
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Simone Tenan Noelia Hernndez Holly Fearnbach Renaud de Stephanis Philippe Verborgh Daniel Oro 《水产资源保护:海洋与淡水生态系统》2020,30(5):949-958
- The Strait of Gibraltar is an important habitat for cetaceans due to its high marine productivity. However, it is also the second most navigated channel in the world, subjecting cetaceans to a high level of vessel traffic, including an established whale‐watching fleet. Both maritime traffic and whale‐watching activities have been shown to impact the behaviour of cetaceans, but little is known about their impact on the demography and dynamics of cetacean populations.
- The aim of this study was to evaluate the impacts of both ferry traffic and whale‐watching vessels on the apparent survival probability of a bottlenose dolphin (Tursiops truncatus) population that occurs in the Strait.
- A Bayesian hierarchical mark–recapture modelling approach was applied to 8 years of photo‐identification data (2002–2009). Apparent annual survival probability was negatively correlated with ferry traffic, which explained >70% of temporal variation in survival, in contrast to whale‐watching, the effect of which was almost negligible. Despite these results, other natural and human‐related factors are likely to drive apparent survival in the study area.
- Abundance increased between 2002 and 2005, and then decreased between 2006 and 2009, while local per‐capita recruitment decreased from 2004 until the end of the study period. These shifts correlated temporally with the construction of a large harbour on the Moroccan coast, which increased maritime traffic significantly, including a 40% increase in ferry traffic that regularly transited the Strait.
- These results highlight the need to better understand the impact of maritime traffic on the demography of the dolphin population in the Strait, in order to implement evidence‐based conservation regulations in a region of high cetacean occurrence.
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The short wavelength sensitive (SWS) opsin gene is expected to contain informative sites for understanding the speciation
of the family Delphinidae, because it is not functional in cetaceans. We determined partial SWS gene sequences from 15 delphinid
species of 12 genera and from harbor porpoise for comparison. We found a 39-bp insertion that was shared by six species (the
insertion group: Delphinus delphis, Delphinus capensis, Stenella longirostris, Stenella coeruleoalba, Lagenodelphis hosei, and Sousa chinensis) and common base substitutions shared by eight species (Stenella frontalis, Tursiops truncatus, and six species of the insertion group). As these insertions and substitutions are not found in the other seven delphinids
or in the cloven-hoofed mammals (which are close to cetaceans), it is suggested that these eight species are more closely
related to each other than to the other species. This hypothesis is supported by phylogenetic analyses. The eight species
with the substitutions formed a clade containing two sister clades, one consisting of the insertion group and the other consisting
of the two other species, in both neighbor-joining and Bayes analyses. Phylogenetic analyses also showed that Lissodelphis borealis and Lagenorhynchus obliquidens are closely related and that their common ancestor diverged from the others at an early stage of delphinid evolution. 相似文献
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瓶鼻海豚和糙齿海豚血清转铁蛋白的初步研究 总被引：1，自引：0，他引：1
血清转铁蛋白(serum transferrin,Tf)是一种非血红素结合铁的β球蛋白[1],其主要功能是负责机体中的Fe3 在吸收、储存和利用部位间的传递[2],供合成红细胞的主要成分—血红蛋白(结合和输送氧气的蛋白)和维持核糖核苷酸还原酶(ribonudeotide reductase)的活性[3]。同时,Tf是脊椎 相似文献
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E.C.M. Parsons C.A. Warburton A. Woods‐Ballard A. Hughes P. Johnston 《水产资源保护:海洋与淡水生态系统》2003,13(5):397-415
- 1. During the tourist season of 2000, interview surveys were conducted with those involved in whale‐watching in West Scotland. The groups included in the study were boat operators (32), visitor‐centre managers (8), tourists on whale‐watching trips (324), general tourists to West Scotland (673) and local residents (189). The latter two groups were interviewed for comparison of responses of those engaged in whale‐watching against the views of the local community and tourists in general. From the data provided by these interviews, estimates for the economic value of this specialist sector of the Scottish tourism industry were calculated.
- 2. Extrapolating from the surveys, in the year 2000, an estimated total of approximately 242 000 tourists were involved in cetacean‐related tourism activities in West Scotland.
- 3. In 2000, 59 full‐time and one part‐time jobs were estimated to be created as the direct result of cetacean‐related tourism, with 38% of these positions being seasonal.
- 4. Cetacean‐related tourism was estimated to account for 2.5% of the total income from tourism in the region. In remote coastal areas, cetacean‐related tourism may account for as much as 12% of the area's total tourism income.
- 5. The direct economic income (i.e. expenditure on excursion tickets) from cetacean tourism activities was estimated to be £1.77 million per annum.
- 6. A 23% of surveyed whale watchers visited West Scotland specifically to go on whale‐watching trips. The associated expenditure (accommodation, travel, food, etc.) from tourists being brought to rural West Scotland solely due to the presence of whales represented £5.1 million in additional tourism income for the region.
- 7. In addition to the above tourists, 16% of surveyed whale watchers stayed in West Scotland an extra night as a result of going on a whale‐watching trip; thus generating a further £0.9 million of additional associated expenditure (extra accommodation, food, etc.).
- 8. The total gross income generated (directly and indirectly) by cetacean‐related tourism in rural West Scotland was estimated at £7.8 million.
- 9. In comparison with established whale‐watching industries (in countries such as the USA, Canada and New Zealand) the total expenditure by tourists on whale watching in West Scotland is low. However, cetacean tourism in West Scotland is still a relatively young industry and still developing.
- 10. The value of the non‐consumptive utilization of cetaceans (i.e. whale‐watching) to rural, coastal communities in West Scotland was three times greater than the value of the consumptive utilization of cetaceans (i.e. commercial whaling) for rural, coastal communities in Norway.
- 11. This study demonstrates that live cetaceans in Scotland can provide notable financial benefits and, therefore, their conservation has an economic value.
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