A Coral Invasion Threatens Tokyo Bay's Ecosystem
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.
This northward expansion of Acropora squarrosa is attributed to rising sea temperatures caused by global warming. The warmer waters have prevented a drop in temperature, leading to the decline of abalone and turban shells that feed on seaweed. This has created an opportunity for coral species like Acropora solitaryensis to take root in the damaged areas.
However, the 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 changing environment is causing a shift in fish populations, creating challenges for fishermen.
Experts believe that the Kuroshio current is playing a role in transporting coral eggs and larvae from southern waters to Tokyo Bay. This, coupled with the prolonged meandering of the current since 2017, has facilitated the transfer of various coral species to the area.
Meanwhile, in southern waters, rising ocean temperatures are causing coral bleaching, where corals expel photosynthetic cells and become white. This phenomenon has been observed in Amami-Oshima island, where a significant portion of corals have bleached and even died.
The contrasting situations in Tokyo Bay and southern waters highlight the complex impact of climate change on marine ecosystems. While some areas experience an increase in coral populations, others face the risk of losing their coral reefs entirely.
Experts emphasize the need for urgent action to address climate change and mitigate its impact on marine life. Reducing carbon emissions and implementing effective conservation measures are crucial to protect the delicate balance of marine ecosystems.