Long-term snow-track indices of a Finnish native mesopredator declined while those of an invasive one increased.

Monitoring both native and invasive species is crucial for understanding their ecological impacts. However, obtaining reliable data can be challenging, especially for elusive species like mesopredators. This study utilized snow-track surveys in Finland (1989-2022) to examine population trends of the invasive raccoon dog and the native red fox.

The habitat preferences of invasive raccoon dog imply elevated risks for wetland-associated prey species.

Habitat preferences of invasive predators determine where and for which prey species they pose a threat upon. This is crucial information for the conservation of endangered prey species because invasive predators pose additional predation on top of that caused by natural predators. In large parts of Europe, the most common invasive mesopredator is the raccoon dog (Nyctereutes procyonoides).