Invasive Fish Species Threatens Swedish Ecosystem
The black-mouthed buttercup, an aggressive and fast-reproducing fish species, is causing concern in Swedish waters. This invasive species poses a threat to native fish by scaring them away and eating their roe. Recent DNA analysis carried out by the IVL Swedish Environmental Institute has revealed that the black-mouthed buttercup has become one of the dominant species in certain areas of the Gulf of Gävle.
Researcher Mikael Dahl from the institute warns that the establishment of the black-mouthed buttercup in Swedish waters could have significant effects on native species and the overall ecosystem. The Gävle Bay has already witnessed large quantities of black-mouthed smolt, and there is a growing concern that it could spread into other waterways around Gävle.
The DNA analysis, which detected traces of DNA left behind by fish, found that the black-mouthed buttercup was the most common fish species in Österviksudden, a southern area of Gävle Bay. The county administrative board has received alarming reports of large catches of black-mouthed buttercup during trial fishing in this area.
Interestingly, the invasive species was also found in lower parts of Gavleån and was common outside harbors in Gävlebukten. However, it was not found in Dalälven and Testeboån. The black-mouthed buttercup is an alien species from the Black Sea and the Caspian Sea.
According to the SLU Species Data Bank, the black-mouthed buttercup is classified as a species with a potentially large ecological effect, capable of establishing itself over large areas in the country. Nearly half of the 100 alien species found in Swedish seas, lakes, and waterways are considered invasive and pose a high risk to biodiversity and ecosystem services.
The Norwegian Sea and Water Authority is the source of this information. To combat the further spread of the black-mouthed buttercup, innovative solutions will be needed. Researchers and authorities are working together to develop strategies to limit the impact of this invasive species and protect native fish populations and the delicate ecosystem they rely on.