辽宁近海外来赤潮海洋微藻入侵现状

<正>外来海洋生物入侵已成为全球性的环境问题之一,而生物入侵对生态系统稳定性的影响以及经济损失,已经引起科学界和社会公众的广泛关注。20世纪及21世纪初运输船舶压舱水排放等导致外来海洋浮游生物广泛传播。本文主要通过收集中国生物多样性数据库、中国外来入侵物种数据库、中国外来海洋生物入侵数据库、全球入侵物种数据库美国海岸警戒压舱水管理项目数据库资料及相关文献,结合辽宁近海历史与近期的调查资料,综     

东莞市自然水域水生动物外来物种的调查与分析

随着经济的发展和运输的发达通畅，广东省东莞市近年来外来水生物种正逐渐增多。外来物种虽部分丰富了东莞的水产种质资源，为水产养殖业发展做出了重要贡献，但有些外来水生动物如果在江河中迅猛繁殖建立自己的种群将成为入侵物种，会使本地的物种面临减少甚至灭绝的危险，     

中国水生外来物种入侵现状和对策

水生外来物种入侵是指某物种在某水域生态系统中原来没有,通过人为有意或无意活动从其它生态系统中引入,一旦该物种在当地形成自己繁殖,并对当地生态或者经济造成破坏,该物种就构成了水生外来物政策导航责任编辑肖乐种入侵。入侵种可能是水生植物或者动物,也可能是一种病毒或细菌。水生外来物种一旦入侵成功,将对当地水生物种的种类、种群结构、食物链结构、生物多样性等产生一系列的影响,威胁渔业生产、经济和生态安全。我国水生外来物种入侵现状我国水生外来物种入侵的总体状况近20年来,随着水产养殖、水簇产业的发展以及资源增殖放流的需…     

水产动物引种的入侵风险

引种就是从不同地区(包括外地和外国)将适合于本地的优良品种或野生类型引进到本地进行养殖开发;某个物种在某个生态系统中原来没有这个物种,是通过人为有意或者无意的从其它生态系统中引入到这个生态系统中,这个物种称为外来物种;而生态入侵是由于人类有意识或无意识地将某些生物带入适宜于其生存和繁衍的地区,它的种群便不断的增加,分布区便会逐步稳定地扩展的过程。一旦外来物种在当地形成自己的群体,将严重影响土著物种的生存及生态平衡的维持,因此,在引种问题上应引起相关部门的重视。一、我国引种现状随着我国水产养殖业的不断发展,许…     

关注外来物种入侵 维护渔业生态平衡

近年来,外来物种入侵已引起人们的忧虑与重视。本文就水生“外来物种”入侵温州水域的现状进行调研,并提出对策。     

环境DNA分析技术—一种水生生物调查新方法

掌握珍稀濒危和外来入侵物种的分布状况对于物种保护和管理十分重要。环境DNA(Environmental DNA)分析通过收集、分离和分析环境样品中的DNA来检测物种是否存在,是一种低耗、高效、高灵敏度的无损伤性物种监测新技术(e DNA)。本文综述了环境DNA技术的发展、分析方案、优势及存在的问题,主要综述了该方法在外来入侵物种足迹追踪、濒危珍稀水生生物资源调查和物种多样性分析中的研究现状,并对环境DNA分析技术在生物多样性保护研究中的应用前景进行了展望。     

保护土著水生物维护湖泊水生态环境安全

近些年,由于水产养殖增产、环境保护、工程安全的需要,从国外引进及国内地区间引植水生生物,加之放生行为日趋普遍、数量逐步增加,这在达到引进、引植目的的同时,也在不同程度上对引入地的生态环境、物种构成产生了不同程度的影响。本文通过分析当前我国外来水生物种入侵的现状及危害,提出保护土著水生物种、抑制外来物种的建议。     

西昌市牛住肉孢子虫病检验报告

<正>肉孢子虫病是由肉孢子虫科(Sar-cocystidae)、肉孢子虫属(Sarcocyshs)的多种寄生虫寄生于猪、牛、羊、马等动物所引起的一种原虫病的总称。肉孢子虫为专性双宿主寄生虫,终末宿主为肉食动物、人等;中间宿主为草食动物和其它杂食动物等。动物的肉孢子虫病通常情况下症状不明显,严重时才有厌食、消瘦、贫血等临床症状,甚至引起死亡。虽然肉孢子虫病死亡率不高,但因虫体寄生致使局部肌肉变性、变质而不能食用,降低肌肉的使用价值,造成一定的经济损失。为了摸     

南极磷虾寄生虫多样性与生态学研究进展:簇虫、线虫和纤毛虫

南极磷虾广泛栖息于环南极水域, 其生物量极为丰富, 为世界上最大的动物蛋白质来源之一。以磷虾(如三刺磷虾 Euphausia. triacantha、瓦氏磷虾 E. vallentini、长额樱磷虾 Thysanoessa macrura 以及南极大磷虾 Euphausia superba)为中间宿主或终末宿主的寄生虫广泛存在于南大洋食物网的不同营养级生物中, 是形成南极生物多样性的重要组成部分。为了充分了解南极磷虾寄生虫的类型、生态特性以及感染机制等, 本文对其种类多样性、生命周期、寄生部位、影响机制、宿主多样性等方面进行系统总结与分析。结果显示, 南极磷虾寄生虫多样性主要集中在同种磷虾感染多种寄生虫以及同种寄生虫感染多种磷虾等; 磷虾体内寄生虫的传播途径基本上为沿食物网传播; 体内寄生虫对宿主的危害大于体外寄生虫; 宿主体长越长, 感染寄生虫越多等。针对今后的研究, 建议重点开展感染机制、发现新寄生虫或宿主等方面的工作, 而利用寄生虫作为生态指示物种开展气候变化对南极的影响将有较好的研究前景。     

勿角自然保护区及邻近水域鱼类区系特征和资源现状

2010年11月、2011年5月对四川省九寨沟勿角自然保护区及其邻近水域鱼类物种多样性进行调查,共采集到鱼类6种,共182尾,隶属于3目4科。其中,土著鱼类5种,外来种1种;鲤形目4种,占鱼类物种数的66.67%,鲇形目和鲑形目各有1种,均占鱼类物种数的16.67%。保护区鱼类主要组成为老第三纪原始类群和青藏高原类群,兼有少量的北方冷水类群。其中长江上游特有鱼类3种,占鱼类物种总数的50%;属于四川省重点保护野生动物的有2种,占鱼类物种总数的33.33%。保护区鱼类在食性和栖息习性等方面分别属于不同的生态类型。掠夺性获取,水环境破坏,以及外来种入侵是保护区鱼类资源面临的最大威胁,针对以上威胁提出了相应的保护对策。     

The effect of foraging and ontogeny on the prevalence and intensity of the invasive parasite Anguillicola crassus in the European eel Anguilla anguilla

Infection patterns of the invasive Anguillicola crassus nematode were investigated in a population of the European eel Anguilla anguilla where parasite invasion is very recent, Loch Lomond, Scotland. Intensity levels of the parasite were associated with differences in fish ontogeny and trophic ecology. Although eels foraged on both fish and invertebrates, individuals which were smaller and fed on invertebrates (>70% contribution to diet) were found to contain a greater number of swim bladder parasites compared to larger eel with a predominance of fish (>60% contribution) in their diet. Within affected fish, a significant negative relationship was found between fish length and parasite intensity, with smaller individuals having higher parasite intensity than larger individuals. This study indicates that food intake and infection risk are linked in this recently infected host–parasite system. From a management perspective increasing our understanding of how infection intensity and repeated exposure is linked to resource use in an ecosystem is important for the future management of this endangered species in Europe.     

Fecundity of the sea louse Caligus rogercresseyi on its native host Eleginops maclovinus captured near salmon farms in southern Chile

The sea louse (Caligus rogercresseyi) is the most significant parasitic pathogen in Chilean salmon farms, and it infects farmed salmon and native host fish. Fecundity is one of the most important parameters for understanding the population dynamics of a species; however, this information is scarce for this parasite. The fecundity of C. rogercresseyi females collected from native hosts (Eleginops maclovinus) captured near salmon farms in southern Chile was measured to evaluate the reproductive output of this parasite on this host fish. From June 2008 to May 2009, 212 specimens of E. maclovinus were examined. Each fish was measured, and all its parasites were collected, sorted and counted. Seventy‐nine ovigerous C. rogercresseyi females (OFs) were measured. Total body length, egg string length and total number of eggs per string were recorded for each parasite. Ovigerous females body length varied between 3.9 and 5.0 mm. Fecundity varied between 12 and 56 eggs string^?1, and it was correlated with OF body length. Temporal variations in OF fecundity were explained by co‐variation in OF body length, but not by month. Ovigerous females on E. maclovinus were smaller and showed lower fecundity than OFs on farmed salmon. Our results suggest that native hosts play a secondary role in C. rogercresseyi egg production in Codigue bay.     

西藏哲古措2种土著鱼类消化道寄生蠕虫的群落结构及感染状况

为了解西藏哲古措土著鱼类消化道寄生蠕虫的群落结构及季节动态，于2018年9月（秋季）和12月（冬季）、2019年3月（春季）和6月（夏季）对哲古措进行了4个季节的采样调查。共采集到2种土著鱼类，分别为高原裸鲤（Gymnocypris waddellii）和异尾高原鳅（Triplophysa stewartii），与原来的记录不同。在高原裸鲤的消化道中采集到了5种寄生蠕虫，分别为聂氏拟短结绦虫（Parabreviscolex niepini）、新棘吻虫未定种（Neoechinorhynchus sp.）、异肉吸虫未定种（Allocreadium sp.）、对盲囊线虫未定种线虫（Contracaecum sp.）和束首线虫未定种（Streptocara sp.），并对形态特征进行了描述。本研究发现，哲古措土著鱼类消化道寄生蠕虫的物种组成具有一定地域性，大部分为广布性寄生虫，鸟类在其传播过程中起到了重要作用。经过分析，高原裸鲤消化道寄生蠕虫群落的Shannon-Wiener多样性指数为0.70~1.27，显示了较高的群落多样性，Berger-Parker优势度指数为0.38~0.76，优势群为线虫。线虫表现出一定的季节消长规律：秋季为周年最高，冬季下降，春季上升，夏季降至最低，推测与水温、中间宿主的种群数量、线虫的生命周期和鱼类宿主繁殖期的行为等有关。复殖吸虫、绦虫和棘头虫四季的感染率均在10%以内浮动，平均丰度也较低。异尾高原鳅的消化道中未发现任何寄生蠕虫，推测与宿主肠道空间大小、摄食量和分布空间的差异有关。本研究通过对西藏湖泊土著鱼类寄生蠕虫的调查与分析，旨在为深入了解西藏寄生虫的组成特点、研究青藏高原隆升对寄生虫与鱼类宿主协同进化提供基础理论依据。     

When alien catfish meet—Resource overlap between the North American Ictalurus punctatus and immature European Silurus glanis in the Arno River (Italy)

Due to the increasing globalisation and ongoing introduction of alien species specifically regarding European freshwater ecosystems, native and already present alien species will be confronted with competitors with unknown outcomes. One such case is the situation of the European catfish Silurus glanis introduced in the Arno River (Central Italy), a species sought after by anglers, which is facing competition from the later introduced alien North American channel catfish Ictalurus punctatus. Large catfish species are highly valued among anglers, but their interspecific interactions and potential ecosystem-level impacts are still poorly known. We used stomach contents and stable isotope analyses to study niche partitioning between these two alien catfish species, coexisting in the Arno River. The results suggest partial niche segregation, with immature S. glanis showing a narrower dietary and isotopic niche and a slightly higher trophic position than I. punctatus. Monitoring the catfish population sizes, trophic niches and effects on lower trophic levels are essential for future management and mitigation of their potential impacts on invaded freshwater ecosystems.     

An alien fish threatens an endangered parasitic bivalve: the relationship between brook trout (Salvelinus fontinalis) and freshwater pearl mussel (Margaritifera margaritifera) in northern Europe

1. Host–parasite interactions may play a significant role in biological invasions: for example, an invader may benefit from lower infectivity by native parasites in competition against the native hosts (‘enemy release hypothesis’).
2. The invasive North American brook trout (Salvelinus fontinalis) is replacing the native salmonid hosts of the freshwater pearl mussel (FPM, Margaritifera margaritifera) in northern Europe, but the suitability of brook trout as a host for FPM is poorly known. In this study its suitability was investigated using an array of laboratory and field experiments, and several FPM populations from a catchment in northern Finland. The occurrence of brook trout in FPM rivers in the area was also studied.
3. There were differences with respect to numbers and size of FPM larvae among the fish exposed to FPM, but generally brook trout was an unsuitable host or was clearly a poorer host for FPM than the native European salmonids, brown trout (Salmo trutta) or Atlantic salmon (Salmo salar). However, in one river a few FPM glochidia remained encysted in wild brook trout for at least 9 months, suggesting successful development – the first observation of its kind in Europe.
4. A tendency was found for higher occurrence of brook trout in brown trout rivers with FPM than in brown trout rivers without FPM, being consistent with the enemy release hypothesis: as FPM infection is costly to the host, a higher glochidial load in brown trout may offer a competitive advantage to brook trout in FPM rivers.
5. Generally, these results indicate that northern European FPM populations cannot typically use brook trout as their host fish. Therefore, the invasion and dispersal of brook trout, potentially leading to the disappearance of native salmonids, should also be considered as a potential threat to the endangered FPM populations.

Copyright © 2016 John Wiley & Sons, Ltd.     

Alien freshwater fish species in the Balkans—Vectors and pathways of introduction

Fish introductions, particularly in areas of high biological diversity and endemism, represent a major threat for biodiversity. In the Balkan Peninsula, 60 fish species have been introduced to date, of which 36 have become naturalized in inland waters. Since the Balkans are one of the world's 35 biodiversity hot spots, this large presence of alien fish species poses a serious threat for the stability of freshwater ecosystems and the survival of the native ichthyofauna and of aquatic biodiversity in general. The motivation for the introductions, and the historical timeline, varies among the Balkan states. Despite recent attempts to implement and align legislation aimed at preventing the introduction of potentially invasive species, and the implementation of rigorous controls of introductions and increased protection of open waters, the majority of current introductions remain intentional, primarily via aquaculture. This review article provides a historical overview of freshwater fish introductions, the motivation behind them and the current distribution of alien freshwater fishes in the Balkans. The ecological implications and future perspectives concerning alien fish species in the region are also discussed.     

Invasive Chinese pond mussel Sinanodonta woodiana threatens native mussel reproduction by inducing cross‐resistance of host fish

1. The effects of invasive alien species (IAS) on host–affiliate relationships are often subtle and remain unnoticed or insufficiently quantified. The global decline of freshwater unionid mussel species has been attributed to many causes, but little is known about the interactions of IAS, with their complex life cycle, which includes an obligatory parasitic stage (the glochidium) that develops on fishes.
2. The capacity of a European freshwater mussel, Anodonta anatina, to develop on its widespread fish host, Squalius cephalus was tested experimentally, after previous infestations by the IAS, Sinanodonta (Anodonta) woodiana. The initial attachment of glochidia, the length of the parasitic period, and the metamorphosis success rate of A. anatina glochidia were compared among treatments of different priming infestation intensities.
3. The metamorphosis success rate of the native A. anatina glochidia was strongly reduced (Wilcoxon Signed‐Rank Test, P < 0.001) and declined by 42.1 and 45.4% on fish hosts that were previously exposed to S. woodiana by single and multiple priming infestations, respectively, in comparison with the control group. Such cross‐resistance is expected to decrease significantly the quality of the host resources available to native mussels.
4. This study provides the first evidence of the host‐mediated adverse impact of invasive S. woodiana on native mussel species. These results also highlight the importance of potential competition for hosts between threatened groups of affiliate species and their invasive counterparts, which should be reflected in conservation strategies.

     

Invasions of rainbow trout and brown trout in Japan: A comparison of invasiveness and impact on native species

Many species of salmonids have been stocked into waters outside of their native range. The invasiveness and impact of these species on native species varies depending on their biological traits, and on environmental conditions, such as climate. In Japan, rainbow trout and brown trout, both listed in 100 of the world's worst invasive alien species by the International Union for Conservation of Nature, occur as non-native species. The invasiveness of these two species is thought to be related to seasonal flooding, given flood waters can physically damage fry and prevent population establishment. Rainbow trout have successfully invaded waters in Hokkaido, northern Japan, where the likelihood of flooding is low between June and July, when their fry emerge, but successful invasions are rare in regions south of Hokkaido. Brown trout, however, have successfully invaded waters not only in Hokkaido, but also other regions. Since brown trout have a similar life history to the native white-spotted charr and masu salmon, with fry emerging before the flood season, they are more suited to the Japanese climate than Rainbow trout. Rainbow and brown trout interact with native species in various ways, but a common outcome of these interactions is the displacement of native charr species. Legal regulations of non-native salmonids should be based on understandings of the ecological traits of each invasive species and regional impacts on native species. Given the ongoing nature of climate change, the nature and extent of the effects of rainbow and brown trout on native species might also change.     

水生动物入侵研究进展

本文介绍了中国大陆外来水生动物的种类和数量,对水生动物入侵的定义、研究范围、研究方法进行综述,提出了今后的水生动物入侵的研究和管理的工作要点。