A pathways risk assessment of aquatic non-indigenous macroinvertebrates passing to, and through, the Central European invasion corridor

A pathways risk assessment is a part of an integrated assessment for the horizon scanning of non-indigenous species introductions. We examined past pathways, and their vectors, of aquatic NIS already present in Belarus in order to predict those species likely to spread to Belarus and arrive to Western Europe along the Central European invasion corridor. Twenty-four aquatic non-indigenous macroinvertebrates are known within Belarusian rivers, lakes and reservoirs, six of these have already spread westwards through Belarus. The modes of spread for these NIS were vessel transport, navigation corridors, and natural spread following an initial introduction

Factors Controlling Diurnal Distribution and Migation of Zooplankton in the Littoral Zone of Freshwater Lakes

Видовое разнообразие зоопланктона в литоральной зоне озер значительно выше, чем в пелагиали озер, в основном за счет представителей родов Chydoridae и Macrotricidae. Большинство видов Cladocera, считающихся преимущественно пелагическими, обычны и в литорали озер. Высокое видовое разнообразие обусловлено гетерогенностью местообитаний в литоральной зоне. Основным фактором, определяющим распределение и суточные миграции зоопланктона, является пресс рыб и беспозвоночных хищников. В разных водоемах обилие фитопланктона может возрастать в направлении литоральной зоны и наоборот, что сказывается на распределении и горизонтальных перемещениях зоопланктона. Метаболиты водной растительности могут оказывать как отрицательный, так и стимулирующий эффект на развитие различных видов фитопланктона, а также содержаться в достаточных концентрациях в литоральной зоне водоемов, чтобы оказать непосредственное влияние на зоопланктон. Экспериментальные исследования показывают, что в отсутствие других сигналов кладоцеры избегают зарослей макрофитов. В водоемах умеренной зоны зоопланктон двигается в направлении макрофитов при наличии кайромонов рыб. Напротив, в субтропической зоне дафнии избегают водной растительности даже в присутствии сигналов от хищников. В умеренных широтах погруженная растительность служит достаточно хорошим рефугиумом для зоопланктона, который может контролировать развитие фитопланктона даже при дополнительном поступлении биогенных веществ. В низких широтах обоих полушарий погруженная растительность служит лишь слабой защитой для зоопланктона от мощного пресса мелких видов рыб, имеющих высокую численность во всех биотопах. Пресс рыб направлен на крупный зоопланктон, тогда как зоопланктон с малыми размерами не способен контролировать развитие фитопланктона. Различия в прессе рыб приводят к тому, что в умеренных мелководных озерах зоопланктон, в основном, совершает горизонтальные миграции, в то время как в субтропических - вертикальные. Кардинальные различия в функционировании водных сообществ в водоемах разных климатических зон могут служить основой для прогноза возможных последствий глобального потепления климата.Species diversity of zooplankton in the littoral zone of lakes is higher than pelagic zone due to presence of the genus Chydoridae и Macrotricidae. The most of cladoceran species which are considered as pelagic are typical in the littoral zone. Higher diversity is determined by heterogeneity of littoral habitats. Fish and invertebrate predator pressure are the main factor influencing on diurnal distribution and migration of zooplankton. In the different lakes phytoplankton abundance may increase as in a direction to the pelagic of water-body and wise versa. The influence of macrophyte metabolites on development of the different phytoplankton species may be both negative and positive. Metabolite concentrations in the natural condition are sufficient to effect directly on zooplankton and other animals. Experiments show that cladocerans avoid macrophyte beds in the absence other signals. In the temperate zone zooplankton migrate in the daytime toward macrophyte beds in the presence of fish kairomones and wise versa in subtropical lakes. Daphnia avoids macrophytes even in the presence of predator cues. Its may be explained by the higher abundance of planktivorous fish and invertebrate predators especially in macrophyte beds of subtropical lakes. macrophyte beds are a good refuge for zooplankton which may control phytoplankton bloom in temperate lakes even under nutrient enrichment. In the low latitudes only submerged vegetation give a weak refuge for zooplankton under strong pressure of predators which have high density in the all habitats. Fish graze preferably of largebody species and small zooplankton cannot provide clear-water control. Furthermore, the differences in fish pressure leads mainly to horizontal zooplankton migrations in the temperate lakes and vertical migrations in the subtropical shallow lakes. Cardinal distinctions in functioning water communities in lakes of different climatic zones may be a basis for the prognosis of possible consequences of global warming

Factors Controlling Diurnal Distribution and Migation of Zooplankton in the Littoral Zone of Freshwater Lakes

Видовое разнообразие зоопланктона в литоральной зоне озер значительно выше, чем в пелагиали озер, в основном за счет представителей родов Chydoridae и Macrotricidae. Большинство видов Cladocera, считающихся преимущественно пелагическими, обычны и в литорали озер. Высокое видовое разнообразие обусловлено гетерогенностью местообитаний в литоральной зоне. Основным фактором, определяющим распределение и суточные миграции зоопланктона, является пресс рыб и беспозвоночных хищников. В разных водоемах обилие фитопланктона может возрастать в направлении литоральной зоны и наоборот, что сказывается на распределении и горизонтальных перемещениях зоопланктона. Метаболиты водной растительности могут оказывать как отрицательный, так и стимулирующий эффект на развитие различных видов фитопланктона, а также содержаться в достаточных концентрациях в литоральной зоне водоемов, чтобы оказать непосредственное влияние на зоопланктон. Экспериментальные исследования показывают, что в отсутствие других сигналов кладоцеры избегают зарослей макрофитов. В водоемах умеренной зоны зоопланктон двигается в направлении макрофитов при наличии кайромонов рыб. Напротив, в субтропической зоне дафнии избегают водной растительности даже в присутствии сигналов от хищников. В умеренных широтах погруженная растительность служит достаточно хорошим рефугиумом для зоопланктона, который может контролировать развитие фитопланктона даже при дополнительном поступлении биогенных веществ. В низких широтах обоих полушарий погруженная растительность служит лишь слабой защитой для зоопланктона от мощного пресса мелких видов рыб, имеющих высокую численность во всех биотопах. Пресс рыб направлен на крупный зоопланктон, тогда как зоопланктон с малыми размерами не способен контролировать развитие фитопланктона. Различия в прессе рыб приводят к тому, что в умеренных мелководных озерах зоопланктон, в основном, совершает горизонтальные миграции, в то время как в субтропических - вертикальные. Кардинальные различия в функционировании водных сообществ в водоемах разных климатических зон могут служить основой для прогноза возможных последствий глобального потепления климата.Species diversity of zooplankton in the littoral zone of lakes is higher than pelagic zone due to presence of the genus Chydoridae и Macrotricidae. The most of cladoceran species which are considered as pelagic are typical in the littoral zone. Higher diversity is determined by heterogeneity of littoral habitats. Fish and invertebrate predator pressure are the main factor influencing on diurnal distribution and migration of zooplankton. In the different lakes phytoplankton abundance may increase as in a direction to the pelagic of water-body and wise versa. The influence of macrophyte metabolites on development of the different phytoplankton species may be both negative and positive. Metabolite concentrations in the natural condition are sufficient to effect directly on zooplankton and other animals. Experiments show that cladocerans avoid macrophyte beds in the absence other signals. In the temperate zone zooplankton migrate in the daytime toward macrophyte beds in the presence of fish kairomones and wise versa in subtropical lakes. Daphnia avoids macrophytes even in the presence of predator cues. Its may be explained by the higher abundance of planktivorous fish and invertebrate predators especially in macrophyte beds of subtropical lakes. macrophyte beds are a good refuge for zooplankton which may control phytoplankton bloom in temperate lakes even under nutrient enrichment. In the low latitudes only submerged vegetation give a weak refuge for zooplankton under strong pressure of predators which have high density in the all habitats. Fish graze preferably of largebody species and small zooplankton cannot provide clear-water control. Furthermore, the differences in fish pressure leads mainly to horizontal zooplankton migrations in the temperate lakes and vertical migrations in the subtropical shallow lakes. Cardinal distinctions in functioning water communities in lakes of different climatic zones may be a basis for the prognosis of possible consequences of global warming

Environmental DNA (eDNA) metabarcoding surveys show evidence of non-indigenous freshwater species invasion to new parts of Eastern Europe

Active environmental DNA (eDNA) surveillance through species-specific amplification has shown increased sensitivity in the detection of non-indigenous species (NIS) compared to traditional approaches. When many NIS are of interest, however, active surveillance decreases in cost- and time-efficiency. Passive surveillance through eDNA metabarcoding takes advantage of the complex DNA signal in environmental samples and facilitates the simultaneous detection of multiple species. While passive eDNA surveillance has previously detected NIS, comparative studies are essential to determine the ability of eDNA metabarcoding to accurately describe the range of invasion for multiple NIS versus alternative approaches. Here, we surveyed twelve sites, covering nine rivers across Belarus for NIS with three different techniques, i.e. an ichthyological, hydrobiological and eDNA survey, whereby DNA was extracted from 500 ml surface water samples and amplified with two 16S rDNA primer assays targeting the fish and macroinvertebrate biodiversity. Nine non-indigenous fish and ten non-indigenous benthic macroinvertebrates were detected by traditional surveys, while seven NIS eDNA signals were picked up, including four fish, one aquatic and two benthic macroinvertebrates. Passive eDNA surveillance extended the range of invasion further north for two invasive fish and identified a new NIS for Belarus, the freshwater jellyfish Craspedacusta sowerbii. False-negative detections for the eDNA survey might be attributed to: (i) preferential amplification of aquatic over benthic macroinvertebrates from surface water samples and (ii) an incomplete reference database. The evidence provided in this study recommends the implementation of both molecular-based and traditional approaches to maximise the probability of early detection of non-native organisms

Risk Assessment of Aquatic Invasive Species Introductions via We stern

The present Atlas of Biodiversity Risk is the first of its kind to describe and summarise in a comprehensive, easy-to-read and richly illustrated form the major pressures, impacts and risks of biodiversity loss at a global level. The main risks identified are caused by global climate and land use change, environmental pollution, loss of pollinators and biological invasions. The impacts and consequences of biodiversity loss are analyzed with a strong focus on socio-economic drivers and their effects on society. Three scenarios of potential futures are the baseline for predicting impacts and explore options for mitigating adverse effects at several spatio-temporal scales. Elements of these futures are modeled, tested and illustrated. The Atlas is divided into sections which mostly deal with particular pressures. It furthermore is based on case studies from a large set of countries, which are completed by introductory and concluding chapters for each section. The Atlas combines the main outcomes of the large European project ALARM (performed by 68 partner organisations from 35 countries from Europe as well as other continents) with some core outputs of numerous further research networks. A total number of 366 authors from 180 institutions in 43 countries provided information and contributed to the Atlas. The Atlas is addressed to a wide spectrum of users. Scientists will find summaries of well-described methods, approaches and case studies. Conservationists and policy makers will use the conclusions and recommendations based on academic research output and presented in a comprehensive and easy-to-read way. Lecturers and teachers will find good examples to illustrate the main challenges in our century of global environmental changes. The Atlas is an indispensible tool to any library or institution in biodiversity and environmental sciences. Finally, all people concerned with environmental issues will find the Atlas a powerful weapon in their fight for saving the life on our Planet!Settele J, Penev LD, Georgiev TA, Grabaum R, Grobelnik V, Hammen V, Klotz S, Kotarac M, Kühn I, editors. Atlas of the Biodiversity Risk. Sofia; Moscow: Pensoft Publishers; 2010. p. 140–3

Alien species in a warmer world: risks and opportunities

Climate change and biological invasions are key processes affecting global biodiversity, yet their effects have usually been considered separately. Here, we emphasise that global warming has enabled alien species to expand into regions in which they previously could not survive and reproduce. Based on a review of climate-mediated biological invasions of plants, invertebrates, fishes and birds, we discuss the ways in which climate change influences biological invasions. We emphasise the role of alien species in a more dynamic context of shifting species’ ranges and changing communities. Under these circumstances, management practices regarding the occurrence of ‘new’ species could range from complete eradication to tolerance and even consideration of the ‘new’ species as an enrichment of local biodiversity and key elements to maintain ecosystem services

Speaking their language – development of a multilingual decision-support tool for communicating invasive species risks to decision makers and stakeholders

Environmental changes due to non-native species introductions and translocations are a global concern. Whilst understanding the causes of bioinvasions is important, there is need for decision-support tools that facilitate effective communication of the potential risks of invasive non-native species to stakeholders. Decision-support tools have been developed mostly in English language only, which increases linguistic uncertainty associated with risk assessments undertaken by assessors not of English mother tongue and who need to communicate outcomes to local stakeholders. To reduce language-based uncertainty, the ‘ecology-of-language’ paradigm was applied when developing the Aquatic Species Invasiveness Screening Kit (AS-ISK), a decision-support tool that offers 32 languages in which to carry out screenings and communicate outcomes to stakeholders. Topics discussed include uncertainty related to language-specific issues encountered during the AS-ISK translation and the potential benefits of a multilingual decision-support tool for reducing linguistic uncertainty and enhancing communication between scientists, environmental managers, policy and decision makers