Invasive freshwater fishes; dispersal vectors, impacts and management

Global biodiversity is rapidly degrading, and two of the main responsible factors are global climate change and biological invasions. Biological invasions may occur when organisms establish viable populations outside their native geographical range. Freshwater ecosystems are particularly vulnerable to biological invasions due to their high degree of isolation, with a native biodiversity largely determined by historical opportunities for dispersal into the geographically restricted localities and subsequent adaptations to the local environment. Invasive species can have significant impacts on recipient ecosystems, for example because the invading species may compete with native species over food resources, may kill them, or may bring in new diseases and parasites. Invasions can be facilitated by human activity, either deliberately as introductions, or accidentally by transport of goods, or organisms can expand their range as the environment is changed or modified. The project INVAFISH will address these issues using Norwegian invasive freshwater fishes as an example. Based upon extensive datasets held by participating institutions, we are developing a risk atlas of invasive freshwater fishes in Norwegian water bodies describing the probability of successful Invasion, secondary dispersal and potential impacts on native ecosystems. The project has been conducted through a collaboration with Norwegian and international institutions. We feed computer models with data on fish distribution, characteristics, management practice and environmental conditions in order to development cost-effective methods for monitoring and mitigation of invasive fishes under both present and anticipated future climate conditions, and to better understand how invasion of new species may influence water quality and local conditions. In close dialog with stakeholders, the project has also conducted prototyping of interactive web tools for managers to get overview of invasion risk in individual waterbodies.

Prosjektet har resultert i konkret oppfølging hvor utviklede data, modeller og verktøy søkes implementert i anvendt forvaltningsarbeid. Dette gjelder hovedsakelig i forhold til handlingsplan for fremmede arter og vannforvaltning. Prosjektet har som en bi-effekt også synliggjort et stort behov for bedre infrastruktur for tilgjengeliggjøring av økologiske forskningsdata. Dette har medvirket som motivasjon til etableringen av et Norsk nettverk for økologiske data (Living Norway ecological data network; LivingNorway) og infrastruktur-søknad til Norges Forskningsråd 2018 (ikke innvilget). Data og modeller produsert av prosjektet er i dag aktivt bruk i en rekke andre FoU prosjekter.

Global climate change and biological invasions, caused either by anthropogenic translocations or native invaders, are among the main factors threatening global biodiversity, ecosystem functioning and associated ecosystem services. Freshwater ecosystems are particularly vulnerable due to their high degree of isolation and endemism. INVAFISH will address these issues using Norwegian invasive freshwater fishes as an example. Based upon extensive datasets held by participating institutions, we will develop a risk atlas of invasive freshwater fishes in Norwegian water bodies describing the probability of successful introductions, secondary dispersal and potential impacts on native ecosystems. This will form the basis for a simulation environment consisting of probabilistic and spatially explicit dispersal models integrated within a GIS visualization environment. Together with input from management practitioners, the modelling and visualization environment forms the basis for development of cost-effective methods for monitoring and mitigation of invasive fishes under both present and anticipated future climate conditions. INVAFISH will also address under which environmental conditions (biotic and abiotic) an invasive fish species may cause the ecological status of a water body to change from one WFD status class to another.