Akashio (赤潮), or red tide, is a red or brown color caused by the rapid and excessive growth of microscopic plankton, including harmful species such as Karenia mikimotoi and Heterosigma akashiwo. Red tide can be overlooked in the broader discussion of Japan as a region, but akashio is an increasingly significant driver of environmental problems in the nation, including significantly affected areas such as the Yatsushiro Sea, Ariake Sea and Hokkaido. Red tide occurrences are significantly influenced by human behaviors, including nutrient rich runoff, coastal pollution and warmer coastal waters due to climate change. The ramifications of akashio can be catastrophic: massive kill-off of finfish and shellfish; significant negative socio-economic impacts for fisheries and tourism; potential threats to human health from toxic species; and weakens marine ecosystem processes. Japan has attempted to implement various countermeasures, including improved water quality policies, improved nutrient and pollution management, improved detection of red tide, and inclusion of people in education improvements about red tide and implications on marine ecosystems. However, younger people also have a directly related role moving into the future. This includes showing an understanding and addressing marine pollution, acknowledging sustainable product consumption, advocating sustainable change in marine or coastal policies, and therefore illustrating an appreciation for marine biodiversity and supporting or advocating for more sustainable practices. This presentation is addressing red tide, a lesser-known and understood but important part of Japan’s environmental landscape, which we collectively implore an understanding of and action from all ages.

Keywords: tide, Japanese region, environmental problem, akashio