Invasive species in freshwater

Last changed: 27 March 2024
Plants below the water surface. Photo.

Invasive species are a growing problem, threatening biodiversity and causing irreversible damage to nature. They can contribute to the extinction of species and ultimately affect human well-being.

To strengthen knowledge and maximise opportunities to manage invasive alien plants and animals, we work on this from different perspectives.

Through environmental monitoring, we help to monitor the occurrence and distribution of invasive species throughout Sweden.

We also have staff who research the ecology of invasive species and the effects of invasions on aquatic ecosystems, and modeling the spread of potential of species.

Our competence, knowledge and experiences include: 

  • Design of monitoring programs (e.g. of the the flooding mosquito and invertebrates in Lake Mälaren).
  • Modelling risk zones (e.g. for the zebra mussel). Used in risk assessment.
  • Using DNA methods to investigate how species (e.g. seaweed) have spread.

Risk zones for zebra mussels. Map.

Modelled risk zones for the invasive zebra mussel. The map is also published in the report Modelling the risks of invasive aquatic species spread in Swedish lakes.


The biological environmental monitoring of Swedish freshwater contains observations of alien species. These observations are recorded in our database and can be used to analyse the consequences of invasions and the potential for spread.