Invasive species in China — an overview

China is a vast country with rich biodiversity, which makes China especially vulnerable to invasive species. It has a long history of introduction of non-native species, especially those with perceived beneficial impacts. Its rapid economic development, including an explosive growth in international trade and transportation, has increased the potential for new introductions. Currently, alien species are widespread in the country, occur in many ecosystems, represent most major taxonomic groups, and are introduced unintentionally as well as intentionally for cultivation. The paper lists various cases of invasive species which have caused significant threats or damages to local natural or artificial ecosystems, and indicates that two example industries (fresh water fisheries and lawn grasses) have brought or tend to bring in many invasive species and hence have caused or will cause changes and loss of biodiversity in local ecosystems. Based on these studies, it is suggested that China combat the problem through enhancing awareness, development of a database on invasive species, strengthening international co-operation, preparing case studies and introducing the necessary legislation, regulations and monitoring.     

淡水鱼类入侵种的分布、入侵途径、机制与后果

生物入侵已经成为全球面临的三大环境问题之一。鱼类入侵现象也随全球经济一体化的进程日益严重。本文综述了全球淡水鱼类入侵的现状和研究进展, 包括鱼类入侵的定义及分布、入侵途径和机制、产生的生态和社会经济影响以及预防措施等。据统计, 目前全球外来鱼类达624种, 该数量超过30年前的两倍。外来鱼类主要通过水产养殖(51%)、观赏渔业(21%)、休闲垂钓(12%)、渔业捕捞运输(7%)等多种途径被引进。入侵鱼类对本地种产生了捕食、种内种间竞争、杂交和疾病传播等负面影响, 破坏本地生态系统, 但是其正面的生态及社会经济影响也不可忽略。近20年来全球鱼类入侵日益受到重视, 相关论文发表数量翻了8倍。值得提出的是, 近10年来全球鱼类入侵风险评价系统的研究显著增加, 一些鱼类入侵模型已应用于五大洲的多个国家。我国淡水外来鱼类共计439种。然而, 我国关于鱼类入侵的研究起步较晚, 发表文献数仅占全球的3.7%, 且主要研究方向仍集中在入侵物种的分布及生物学特性等基础研究上, 缺乏对于鱼类入侵机制及风险评价预测的研究。因此, 我们建议: (1)开展全国范围的本底调查并建立数据库, 实现数据共享, 明确鱼类入侵的历史与分布现状; (2)联合多个政府部门和机构, 对鱼类入侵进行长期观测, 从整个水生生态系统的角度出发, 深入了解其入侵机制及其产生的正面和负面生态和社会经济影响; (3)加强增殖放流的科学研究和管理; (4)构建区域性外来鱼类入侵风险评价系统, 有效预测鱼类入侵活动, 评价入侵种的危害, 并为相关政府部门的决策提供科学依据。     

Global distribution,entry routes,mechanisms and consequences of invasive freshwater fish

Biological invasion is now considered one of the three major environmental issues worldwide. Freshwater fish invasion becomes more serious with globalization of the world economy. We reviewed the current status of global freshwater fish invasions and discussed the definitions, distributions, introduction pathways, mechanisms, ecological and economic impacts, and risk assessments of freshwater fish invasions. Non-native fish are mainly introduced through food aquaculture (51%), as ornamental fish (21%), or for sport fishing (12%) and fisheries (7%). The number of introduced fish has reached 624 species, doubled the number found thirty years ago. Successful invasions may bring many negative ecological consequences, such as predation, hybridization, structure and function alteration of local freshwater ecosystems, as well as diseases transmission. However, it also brings positive biological and economic values. The number of fish invasion studies has increased eight times over the last 20 years, with studies mainly focusing on biology and the biological impact of invasive fish species. Risk assessments of freshwater fish invasions were studied over the last 10 years, and fish invasiveness screening models have been applied in countries of five continents. The number of non-native freshwater fish in China totaled 439. However, research papers on freshwater fish invasions in China was only 3.7% of the global total, and these researches were mainly on the distribution and biology of invasive fish species, and very few studies included risk assessments. Therefore, we suggest investigating the history, distribution, and mechanisms of invasive species at the national level, evaluating both the positive and negative effects of freshwater fish invasions, and also reinforcing studies of risk assessments in China.     

“世界100种恶性外来入侵物种”在我国大陆的入侵现状

[目的] 明确世界自然保护联盟公布的“世界100种恶性外来入侵物种”在我国大陆发生分布现状,为我国制定外来入侵物种管控对象和分级管理对策提供依据。[方法] 基于在线数据库系统、文献报道以及外来入侵物种本底调查结果,采用分类统计方法,对物种的分类地位、原产地、在我国的入侵状态及其所在的生态系统进行分析。[结果] 世界100种恶性外来入侵物种已有82种在我国发生分布,包括本地种33种、外来入侵种32种、外来非入侵种16种,以及未明确入侵状态1种。其中,32种外来入侵种包括陆生无脊椎动物8种、哺乳动物2种、鱼类2种、两栖动物1种、爬行动物1种、水生无脊椎动物2种、陆生植物9种、水生植物4种、真菌1种、卵菌1种和病毒1种。以上物种主要分布在东南沿海地区和西南地区,而较少分布在西北地区和东北地区;约75%物种分布在农田、城镇、森林和湿地4类生态系统。[结论] 建议外来入侵物种管理部门重点关注尚未在国内发生分布的18种潜在外来入侵物种,并列入国家外来入侵物种相关管理对象,严防其传入与扩散;严密监控国内已发生且具有潜在危险的外来物种,防止其向可能入侵的生态系统边缘扩散;继续对在国内已发生的外来入侵种实施区域性分级控制管理措施。     

Non-native fish in aquaculture and sport fishing in Brazil: economic benefits versus risks to fish diversity in the upper River Paraná Basin

Brazil has a highly diverse freshwater fish fauna and their freshwaters provide valuable provisioning ecosystem services in aquaculture and sport angling, especially in the developed regions in the south. Non-native fish now comprise a substantial proportion of the total aquaculture production and value, contributing at least $US 250?million in 2008 (63% of the total value of freshwater fish aquaculture) according to the Fish and Agriculture Organisation. Much of this aquaculture activity is centred in Central and Southern Brazil, such as impounded sections of the upper River Paraná. The non-native fishes used tend to feed at relatively low trophic levels, with the most prominently species being Cyprinus carpio and Oreochromis niloticus. Ecological risk assessment suggests these species are potentially highly invasive and deleterious to the native fish diversity of invaded water bodies. Fishes introduced for the creation of sport fisheries tend feed higher trophic levels through piscivory, such as the peacock basses (Cichla species) from Amazonia. Their introductions have generally resulted in establishment and invasion, which tends to be followed by significant and rapid declines in native fish diversity as a consequence of increased predation pressure. Thus, whilst non-native fish in the upper Paraná River support provisioning ecosystem services of substantial economic value, the principal species used represent high risks to fish diversity and conservation. It is recommended local management should concentrate on reducing these risks through use of more appropriate species in these ecosystem services, with these decisions derived using risk assessment and precautionary principles.     

Conservation physiology of marine fishes: advancing the predictive capacity of models

At the end of May, 17 scientists involved in an EU COST Action on Conservation Physiology of Marine Fishes met in Oristano, Sardinia, to discuss how physiology can be better used in modelling tools to aid in management of marine ecosystems. Current modelling approaches incorporate physiology to different extents, ranging from no explicit consideration to detailed physiological mechanisms, and across scales from a single fish to global fishery resources. Biologists from different sub-disciplines are collaborating to rise to the challenge of projecting future changes in distribution and productivity, assessing risks for local populations, or predicting and mitigating the spread of invasive species.     

Impact on indigenous species biodiversity caused by the globalisation of alien recreational freshwater fisheries

One of the most insidious threats to fish conservation around the world is deliberate or accidental introduction of fish species. The impact of alien invasive sport fish is for the most part unpredictable in time and space, with the introduction of relatively few species having resulted in many extirpations of indigenous fish species worldwide. More nations need to quantify biodiversity loss caused by alien sport fishes. The spread of alien invasive fishes does not respect political boundaries. Therefore total global costs to aquatic biodiversity and ecosystem functioning resulting from these introductions need to be assessed. The global invasive species database of the Global Invasive Species Programme, highlights eight fish species among the one hundred `World's Worst Invasive Alien Species'. Three of these fish species (two trout and one bass species) were introduced solely for sport. Historically the social value of recreational fishing was usually more important than conserving biodiversity. Globalisation of alien fish species for sport is best illustrated by rainbow trout – now in 82 countries, and still spreading, along with the associated expensive angling gear, magazines and accommodation infrastructure. Such sport species have become part of the global consumer society. The nature and extent of the globalisation phenomenon is addressed with regard to how introduction of alien fish for recreational angling has impacted on biodiversity; trophic cascades at a local level and the unassessed total cumulative global trophic cascades; and some of the motives that underlie promotion of this sport within the complexity of globalisation as we know it today. Alien invasive recreational fish species are now recognised as a global environmental degradation problem resulting in loss of biodiversity and therefore require a global solution. Parallel trends such as globalisation of environmental education and the internet must be encouraged to counteract the damage caused and reverse the trend. This globally concerted campaign requires utilizing environmental education forums aimed at the angling community, general public and policy makers; networking with existing alien invasive groups; legislation; better understanding of processes; development of environmental economic evaluation tools; international bio-invasion control; wider use of the precautionary approach and utilization of the present globalisation of ecological thought.     

Overlapping niches between two co-occurring invasive fish: the topmouth gudgeon Pseudorasbora parva and the common bleak Alburnus alburnus

Invasive fish species impact aquatic ecosystems and modify native communities, often leading to a decline in local species. These ecological impacts include the transmission of pathogens, predation, competition as well as hybridization. Two invasive fish species, the common bleak Alburnus alburnus and the topmouth gudgeon Pseudorabora parva, have both been recently found co-occurring in several regions of southern Europe, such as the Italian Arno River. Nonetheless, the trophic relationships among invasive fish species, especially cyprinids, remain poorly understood, and no studies have reported the trophic interaction between these two species. This study compared length–weight relationship and used stomach content and stable isotope analysis of two co-occurring populations in the Arno River to characterize the growth and overlap of potential trophic niches. It also found similar allometric growth in both species, a wider generalist trophic niche for P. parva and a more specialized niche for A. alburnus. A considerable niche overlap was found, suggesting that feeding competition can occur if resources were to be limited. Moreover, the niche of P. parva was more likely to overlap with that of A. alburnus than vice versa, suggesting that P. parva can be considered as a potential over competitor. Nonetheless, the authors found in the overlapping populations no evidence of realized competition, probably avoided through a combination of fine-scale mechanisms. They also highlighted that these two invasive species can co-exist and share resources, at least in an open ecosystem like a river, thus potentially doubling up their trophic impact on local communities.     

Characteristics of the introduced fish fauna of Israel

Fishes have been introduced worldwide with deleterious effects on various native ecosystems. To gain insight into this phenomenon in Israel, we studied the introduced ichthyofauna. There are 27 species of introduced fishes in the freshwater habitats of Israel, a large number for a nation this size. Ten of these species reproduce in the wild. Most of these fishes were introduced for aquaculture; some are constantly restocked. The proportion of restocked versus established species in Israel is high compared to other regions. New fish introductions continue in recent decades, unlike the global trend. In Israel these species are found in the Jordan Basin, Lake Kinneret (Sea of Galilee), and the coastal plain rivers. A few species are widespread, and most are found in Lake Kinneret. Harmful effects of introduced fishes have been suspected and in several cases demonstrated. We encourage further caution when new introductions are contemplated; in some regions eradication should be attempted.     

Detection of invasive freshwater fish species using environmental DNA survey

Invasive species are one of the most significant problem in freshwater ecosystems. Most common non-native freshwater species in Turkish freshwater fish fauna are Prussian Carp (Carassius gibelio), North African Catfish (Clarias gariepinus), Nile Tilapia (Oreochromis niloticus) and Topmouth Gudgeon (Pseudorasbora parva).Recent studies showed that environmental DNA could be used to detect target species inhabiting the ecosystem with higher precision and less effort compared to traditional field surveys. In this study, eDNA approach was used to investigate non-native freshwater fish species from fifteen different locations of Upper Sakarya Basin. eDNA was successfully extracted from the water samples of locations where the species were visually observed. Mean amplification rate of eDNA was calculated as 77.03%.This study is the first environmental DNA study used in detection of four of the most common invasive freshwater fish species. Results clearly indicating that eDNA surveys could be used as an important molecular tool to monitor invasive fish species in freshwater ecosystems.     

新世纪的中国昆虫系统学

对未来我国昆虫系统学在能力建设、物种编目、理论研究、技术创新和国际合作等方面提出一系列建议。在昆虫系统学能力建设方面,政府和科学家应该在生物分类学能力评估、基础硬件建设、各级生物标本馆中建立伙伴关系（包括标本采集、标本馆管理、 科学研究、 知识共享和标本与资料交换）等方面重点开展工作。在物种编目方面,我国的昆虫物种编目有赖于各级政府和机构继续关注标本的收集和保藏,继续启动一些考察项目,以满足发现和认识昆虫物种的实际需求。在物种水平上研究以往昆虫系统学家的工作,进行地区性和世界性的昆虫类群的订正更是非常必要的。在理论研究方面,我国昆虫系统应该在下列方面积极探索：物种概念、进化理论、比较生物学理论和高级分类系统研究。在技术创新方面,我国的昆虫系统学家应该在数据库与网络技术应用、图形图像处理技术、专家鉴定系统技术、分类性状分析技术、分子生物学技术、系统发育推断程序、信息统一管理技术和知识传播技术等方面进行深入研究,以满足昆虫系统学的发展需求。在国际合作方面,要进一步推动我国昆虫系统学研究机构加入生物分类学全球战略联盟、加入各种相关国际相关组织,要促进物种信息管理系统的建立与共享,要推动研究项目国际化。     

The genetic characteristics of invasive Largemouth Bass in southern Brazil

Largemouth Bass (Micropterus salmoides) have been introduced on a global scale for sport fishing but represent a conservation concern given their documented negative impacts on native faunal diversity and abundance. Recent research using molecular data to characterize invasive Largemouth Bass populations elsewhere has demonstrated that populations are typically characterized by limited genetic diversity, or represent a combination of Largemouth Bass and Florida Bass (Micropterus floridanus). To test whether these traits were consistent with invasive populations in Brazil, we generated mitochondrial sequence data from four established populations of Largemouth Bass collected in southern Brazil as well as a local aquaculture facility to confirm species identity and quantify levels of genetic diversity. We identified the exclusive presence of Largemouth Bass in the region and observed limited levels of haplotype (haplotype diversity = 0.0684, SE = 0.038) and nucleotide diversity (0.0003, SE = 0.0002) which suggested the presence of a founder effect associated with introduction. Each of the four populations were dominated by a single haplotype that was identical to one recovered from a nearby aquaculture facility, which identified this facility as a potential introduction source.     

The first record of the swordtail Xiphophorus hellerii Heckel, 1848 (Poeciliidae,Actinopterygii) established in the wild from Morocco

Aquarium and ornamental fish trade is currently recognized as a major source of invasive species in aquatic ecosystems around the world. The swordtail Xyphophorus hellerii is a popular ornamental freshwater fish that occurs as an introduced species in the aquatic habitats of at least thirty-one countries. We report the first finding of an established population of the swordtail in Morocco. Twelve individuals of X. hellerii were captured along Oued Ain Chkef inside the park (Fez Province), including females and males (mature and immature). Ongoing investigations could soon reveal more occurrences of this species in the country.     

Aliens in caves: the global dimension of biological invasions in subterranean ecosystems

Alien species are a significant threat to natural ecosystems and human economies. Despite global efforts to address this challenge, the documented number of alien species is rapidly increasing worldwide. However, the magnitude of the impact of alien species may vary significantly across habitats. For example, some habitats are naturally less prone to biological invasions due to stringent abiotic and biotic characteristics, selecting for a limited number of introduced species possessing traits closely related to the native organisms. Subterranean ecosystems are quintessential examples of habitats with strong environmental filters (e.g. lack of light and scarcity of food), driving convergent adaptations in species that have successfully adapted to life in darkness. Despite these stringent environmental constraints, the number of records of alien species in subterranean ecosystems has increased in recent decades, but the relevant literature remains largely fragmented and mostly anecdotal. Therefore, even though caves are generally considered very fragile ecosystems, their susceptibility to impacts by alien species remains untested other than for some very specific cases. We provide the first systematic literature survey to synthesise available knowledge on alien species in subterranean ecosystems globally. This review is supported by a database summarising the available literature, aiming to identify gaps in the distribution and spread of alien invertebrate species in subterranean habitats, and laying the foundations for future management practices and interventions. First, we quantitatively assessed the current knowledge of alien species in subterranean ecosystems to shed light on broader questions about taxonomic biases, geographical patterns, modes of dispersal, pathways for introductions and potential impacts. Secondly, we collected species-specific traits for each recorded alien species and tested whether subterranean habitats act as ecological filters for their establishment, favouring organisms with pre-adaptive traits suitable for subterranean life. We found information on the presence of 246 subterranean alien species belonging to 18 different classes. The dominant alien species were invertebrates, especially insects and arachnids. Most species were reported in terrestrial subterranean habitats from all continents except Antarctica. Palaearctic and Nearctic biogeographic regions represented the main source of alien species. The main routes of introductions into the recipient country are linked to commercial activities (84.3% of cases for which there was information available). Negative impacts have been documented for a small number of case studies (22.7%), mostly related to increased competition with native species. For a limited number of case studies (6.1%), management strategies were reported but the effectiveness of these interventions has rarely been quantified. Accordingly, information on costs is very limited. Approximately half of the species in our database can be considered established in subterranean habitats. According to our results, the presence of suitable traits grants access to the stringent environmental filter posed by subterranean environments, facilitating establishment in the new habitat. We recommend that future studies deepen the understanding of invasiveness into subterranean habitats, raising public and scientific community awareness of preserving these fragile ecosystems.     

全球外来入侵生物与植物有害生物数据库的比较评价

[目的]为了明确全球生物安全与植物保护领域内数据库建设进展和我国数据库的建设成效,对全球重要的外来入侵生物与植物有害生物数据库进行分类介绍和比较评价研究.[方法]根据数据库收录物种的地理范围、类群及数据库特色功能,对数据库进行分类.对重要数据库的主要功能进行简要介绍,设立多指标评价体系将我国数据库与国际优质数据库进行比...     

Food safety and products from aquaculture

Aquaculture is currently one of the fastest growing food production systems in the world with production increasing at an average rate of 9.6% per year over the past decade. As world fish stocks are reaching the limits of exploitation, we shall rely to a far greater extent on products from aquaculture as food sources of high nutritional value. Approximately 90% of global aquaculture production is based in Asia, where it provides an important source of dietary animal protein of the region and income for millions of small-scale farmers. Commercial aquaculture contributes significantly to the economies of many producing countries, where highly valued species are a major source of foreign. Many different aquaculture systems exist world wide, ranging from small family-sized fish ponds to intensive cage culture industries as used in salmon fishing. There has been an expansion in the use of integrated farming systems, especially in Asia, where animal and human faeces are used to fertilise ponds. This paper will review global aquaculture systems used in the production of finfish and crustaceans and will focus on potential hazards arising from biological contamination of products that pose risks to public health.     

Dietary self-selection in fish: a new approach to studying fish nutrition and feeding behavior

The principles of modern aquaculture encourage the development of fish feeds containing low fish meal content and several types of plant ingredients plus nutrients to avoid depleting global fish stocks and to reduce costs. However, food constituents can affect animal nutrition and feeding behavior, so the effect of different diets on fish behavior and growth needs to be understood to optimize the use of nutrients and to improve fish welfare. The development of multiple-choice self-feeding systems led to a new perspective for investigating these issues in aquaculture species. Our purpose with this review is to summarize the information that has been published to date on this topic and to identify gaps in knowledge where research is needed. Key subjects are assessed under the following major headings: How do we study dietary selection in fish? What food signals do fish use to choose the right diet? and How do fish respond to food challenges? The present review will provide a picture of the main results obtained to date in these studies in aquaculture fish species, as well as perspectives for future research in the field.     

The ant community response to the arrival of Monomorium sydneyense forel (Hymenoptera: Formicidae) at sulphur point,Tauranga, New Zealand

Abstract

Impacts of highly invasive ants in new ecosystems are well documented, but many more ant species are establishing in new ranges for which there is little or no information. We studied the effects of the recently discovered Australian ant, Monomorium sydneyense Forel, on the ant community of Sulphur Point in Tauranga, New Zealand. At the community scale, the species composition in invaded areas was significantly different from that in areas free of M. sydneyense. However, no single ant species was significantly more or less abundant in the presence of M. sydneyense. Some resident ant species categorised in the same functional group as the invader appeared to be scarcer when sympatric with M. sydneyense, but the local abundances of these species were always spatially variable, so the effects were not statistically significant Patchy distribution of M. sydneyense, and other aspects of its behaviour, such as poor foraging abilities and a lack of unicoloniality (where there is little or no aggression between conspecific ants from spatially separate nests), appear to allow resident ant species to coexist with M. sydneyense at Sulphur Point.     

生物多样性信息学研究进展

生物多样性信息学是一门蓬勃发展的新学科。它将现代的信息技术带入生物多样性及其相关学科的研究领域。它在生物多样性基础数据的数字化、模型工具和各种工具软件的开发、数据整合, 以及全球、地区和国家尺度生物多样性信息网络等多个方面的发展, 向我们展示了未来在全球范围内自由、免费共享生物多样性数据和信息, 以及人们行动起来共同关注、调查与监测野外生物多样性的前景。目前, 已有大量数字化的物种编目、标本馆标本、多媒体影像、研究文献等生物多样性基础信息可以通过互联网检索和利用。其中, 最值得关注的是一些成功的国际性研究项目, 如物种2000、全球生物多样性信息网络、生命条形码以及网络生命大百科全书。这些项目的成功不仅体现在对大量基础信息和数据的发布, 而且它们通过与生物多样性信息标准TDWG(Biodiversity Information Standards: TDWG)的合作, 推动了达尔文核心标准(Darwin Core)等一些重要的生物多样性信息标准的应用, 以及地区和国家性生物多样性信息节点的建立, 这些都为将来全球范围生物多样性信息的共享和数据交换奠定了重要基础。在数字化信息的基础上, 研究人员也开发了一些在特定研究领域应用的数据挖掘和模型工具, 例如基于数字化标本的地理分布预测工具MAXENT, 分类学专家知识管理的LifeDesk。公民科学理念的发展则向我们展示了公众和科学爱好者广泛参与以互联网为基础的生物多样性信息学研究活动。因此, 生物多样性信息学的发展前景广阔, 它将为我们实现全球保护战略目标, 应对生物多样性危机, 解决全球气候变化条件下生物多样性资源管理和利用建立坚实的信息基础。     

The distribution and economic losses of alien species invasion to China

Invasive alien species have become one of the most serious environmental issues in the world. Data of taxon, origin, pathway, and environmental impacts of invasive alien microorganisms, invertebrates, amphibians and reptiles, fish, birds, mammals, herbs, trees, and, marine organisms in terrestrial, aquatic, and marine ecosystems of China were analyzed during 2001 and 2003, based on literature retrieval and field survey. There were 283 invasive alien species in China, and the number of species of invasive alien microorganisms, aquatic plants, terrestrial plants, aquatic invertebrates, terrestrial invertebrates, amphibians and reptiles, fish, and mammals were 19, 18, 170, 25, 33, 3, 10, and 5, respectively. The proportion of invasive alien species originated from America, Europe, Asia, Africa, and Oceania were 55.1, 21.7, 9.9, 8.1, and 0.6%, respectively. Methods for estimation of direct economic losses to agriculture, forestry, stockbreeding, fishery, road and water transportation, storage, water conservancy, environment and public facilities, and human health were established. Methods for estimation of indirect economic losses caused by invasive alien species to service functions of forest ecosystems, agricultural ecosystems, grassland ecosystems, and wetland ecosystems were also established. The total economic losses caused by invasive alien species to China were to the time of USD 14.45 billion, with direct and indirect economic losses accounting for 16.59% and 83.41% of total economic losses, respectively.