112 Foreign Species Enter Japanese Waters, Global Warming is Suspected to Play a Role

JAKARTA - At least 112 foreign species have entered Japanese waters since the late 1800s. Some have begun to spread north. The change is thought to be related to global warming which has increased sea temperatures.

Quoted from a Kyodo News report, Saturday, June 6, the findings came from a team of marine biologists in Japan. The foreign species include crustaceans such as crabs, mollusks, pathogens, and parasites.

Some of these organisms can damage farmed fish and shellfish. In certain cases, the impact can trigger mass death.

The research team assessed that foreign marine organisms are increasingly impacting the ecosystem and Japanese water resources. However, the handling measures are not considered fast enough. The increasingly warm sea helps some species spread to the north.

Keiji Iwasaki, professor emeritus of biogeography at Nara University, highlighted Japan's slow response. He is concerned because only a few foreign organisms have been designated as invasive alien species. The status is important because it can serve as the basis for import and transportation restrictions.

Of the 112 species found, 77 are suspected of entering Japan accidentally. The routes include ship ballast water or sticking to the hull of the ship. Ballast water is water that is put into a ship to maintain balance while sailing.

According to a Kyodo News report, about 70 percent of the 77 species are estimated to have settled and developed in Japan. This means that the organisms not only pass through, but have become part of the local waters.

This study was led by members of the Japanese Association of Benthology along with marine biologists from various regions of Japan. They collected more than 7,400 records from 36 people between 2022 and 2023.

This finding shows that global warming is also changing life in the sea. As water temperatures rise, species that were once difficult to survive in certain areas can enter, settle, and then affect existing ecosystems.