Study Finds 112 Invasive Species in Japanese Waters

A new study has identified at least 112 non-native species in Japanese waters since the late 19th century, raising concerns over the growing impact of invasive marine life on ecosystems and aquaculture.

Researchers found that many of the species, including crabs, mollusks, parasites, and pathogens, have spread northward as rising sea temperatures create more favorable conditions. Some are known to damage farmed fish and shellfish, occasionally causing mass die-offs.

The study revealed that 77 species were likely introduced unintentionally, primarily through ship ballast water and vessel hulls, with around 70% now established in Japanese waters.

Scientists warned that efforts to address invasive marine species have lagged behind the pace of environmental change, calling for stronger measures to combat global warming and protect marine biodiversity.

The research was conducted by marine biologists from across Japan and was based on more than 7,400 records collected between 2022 and 2023.