A Coral Invasion Threatens Tokyo Bay Ecosystems
the spread of a coral species typically found in western and southern Japan. This coral, Acropora squarrosa, has created a vibrant coral reef near the Boso Peninsula, resembling a tropical scene.
The discovery of this coral reef was made by a diver exploring the area off the Katsuyama district in Kyonan, Chiba Prefecture. The diver encountered a 100-square-meter carpet of corals on the seafloor, teeming with colorful fish like neon damsel and orange sea goldie.
This coral invasion is attributed to changes in the marine environment caused by global warming. Warmer water temperatures have prevented rocky-shore denudation and declines in abalone and turban shells, creating favorable conditions for coral growth.
However, this coral invasion poses a threat to the existing ecosystem. The table-shaped corals block sunlight and inhibit seaweed growth, impacting fisheries that rely on seaweed. Additionally, the shift in fish populations due to the changing environment is causing difficulties for fishermen.
Experts believe that the Kuroshio current is carrying coral eggs and larvae from southern waters to Tokyo Bay, contributing to the coral expansion. Meanwhile, rising ocean temperatures in southern waters are causing coral bleaching and death.
The situation highlights the impact of climate change on marine ecosystems. While Tokyo Bay experiences an influx of corals, southern reefs are facing extinction. This emphasizes the need for urgent action to mitigate climate change and protect marine biodiversity.