Raccoon dogs, which historically inhabited the territories of China, Korea, Japan and Siberia, roam the forests of Latvia. Amur sleepers, fish whose natural range covers the river basins of the Far East, live in the lakes. These are just a few examples of the non-native species of plants, animals, insects and other living organisms that are spreading in Latvia and affecting natural ecosystems.

This is nothing good, as such invasive species have a destructive impact on nature, the economy and even human health, and they are the second leading cause of biodiversity loss after habitat change, the Nature Conservation Agency (DAP) emphasises.

Faster, hungrier and more competitive

DAP specialists explain that an invasive species can be any type of living organism – a plant, insect, fish, fungus, bacterium or even the seeds of an organism. The label "invasive" is usually given to non-native species that, upon reaching new habitats, can begin to multiply rapidly, spread aggressively, suppress native species and threaten ecosystems, as well as cause damage to both nature and people.

If a new species enters an ecosystem, it may have no natural enemies or regulating factors, and then it is capable of multiplying rapidly and taking over large areas. It takes a long time for local wild plants or animals to develop protection against an intruder, which is why they cannot compete with a rapidly arriving species in the struggle for food resources and living space. Another unpleasant aspect is the transmission of diseases, which threatens the health and life of local plants or animals.

"Often, people themselves, even without intending any harm, can cause damage to nature that remains for hundreds of years," says Santa Rutkovska, an invasive species expert at the DAP "LIFE IP LatViaNature" project, explaining the situation regarding the spread of invasive species in Latvia.