Graduate School of Agricultural and Life Sciences, The University of Tokyo

Creatures of the Tokyo Bay's tidal flats

Japan's coastlines, particularly those around urban areas, have undergone extensive development since the 1960s. The coastal tidal flats and reed beds have been reclaimed, and many coastlines have been replaced with concrete seawalls. However, even in Tokyo Bay, one of Japan's most developed areas, a few remaining tidal flats and reed beds still remain, which serve as habitats for organisms adapted to these environments. Studying the ecology of these organisms not only sparks pure curiosity about new discoveries but also provides essential information for developing conservation strategies. As we enter the 21st century, the values of the times are gradually shifting from development to conservation. While the names of the mudskippers in the reed beds and the sandworms and clams of the tidal flats-while have become known, much about their ecology remains unknown, making them fascinating research subjects for the times. Our research is conducted on such organisms in the tidal flats of Tokyo Bay.

Let's walk among the tidal flats.

Our group conducts research on shallow-water organisms using the valuable tidal flats that remain in Tokyo Bay as our field site. The organisms we study range from the benthic microalgae centered on diatoms measuring just a few micrometers in size, to polychaetes such as ragworms measuring several millimeters, crabs and bivalves measuring several centimeters, and even larger species like stingrays measuring tens of centimeters. We wade through the muddy tidal flats in search of these organisms. Although the remaining tidal flats in Tokyo Bay are a valuable ecosystem, the people living in the surrounding areas, especially those in the upstream watershed, do not show much interest in them. While our research on tidal flat organisms cannot directly save the tidal flats, we believe that the findings from our studies can serve as a catalyst for raising public awareness and help mitigate the impacts of human activities on coastal ecosystems. Our graduates often pursue careers in fisheries-related research institutions, industries handling aquatic products, companies conducting water environment surveys, and other water-related fields.

Through students

We benefit greatly from ecosystems, including biodiversity, in various ways, and there is no doubt that their conservation is now necessary. While it is important to protect coastal areas, they are also places where industries and communities thrive, thus making them sites where the challenges of conservation and development are complex and intertwined. In cases like this, findings from research rarely provide a magic solution. It is important that more people, including those with no direct connection to the issue, take an interest in it. One way to achieve this is by educating young people. Therefore, in our laboratory, we have incorporated the theme of “conservation of mudskippers in the Edo River diversion channel”into our student internship program “Coastal Ecology”, inviting external lecturers to teach a curriculum that explores how to engage with complex social issues. We, researchers at universities, curators at a local museum who are knowledgeable about mudskippers, construction company professionals who use eco-friendly construction methods, and students with aspirations for the future, gathered at the same tidal flat to observe mudskippers. We feel that the interaction between people with diverse perspectives has been a great stimulus and has brought about some kind of change in all of us. We hope to continue increasing opportunities like this, focusing on social issues related to coastal ecology.