The invasive Chinese mitten crab has caught the attention of the Swedish media, as it's on its way to reproducing in Swedish lakes.
For several years, the Chinese mitten crab has been present in Swedish lakes, most likely introduced through ballast water from international shipping. Until recently, the species was unable to reproduce in Sweden's colder climate, which limited its spread.
However, new findings from research teams in Belgium and Germany show the emergence of hybdrids with the Japanese mitten crabs. This hybrid variant is capable of reproducing in lower temperatures, significantly increasing the risk of establishment in northern regions.
"If an introgression of the Japanese mitten crab were to be found in Sweden, the probability of establishing itself is higher', says Sonja Leidenberger, reasearch leader in Sweden for Clancy. The potential consequences for local biodiversity could be severe, as mitten crabs are known to cause ecological and economic damage.
To monitor the situation, the Swedish partner University of Skövde is conducting DNA analyses of mitten crabs caught by local fishermen. These tests help track which species or hybrids are currently present in Swedish waters and support early detection of invasive variants.
