Coastal areas have recently been revaluated to understand the relationship between ecosystem services and humans. However, devastation from the 2011 earthquake and tsunami in Japan might have limited the use of ecosystem services. Thus, we investigate the effects of the earthquake and tsunami on the use of tidal flats. We used questionnaires to evaluate changes in the number and anxiety of users for each type of use of the Sanbanze tidal flat in the innermost part of Tokyo Bay. We also conducted a field survey to verify the trends. We found that clamming and walking or jogging were the most common uses in the surveyed area. However, clamming activity decreased after the earthquake as indicated by field observation (73% decrease in spring long holiday season) and questionnaires (64%). Other clamming ground in Tokyo Bay also showed a similar decrease (62%). Many visitors were anxious about the damaged infrastructure. Compared to other types of use such as swimming or total tourism in the tourism statistics, the recovery phase was slower for clamming using the data of other locations. Considering these evidence, the innermost part of Tokyo Bay can be classified as an earthquake-devastated area, from the view point of ecosystem services. Key Words： behavioral change, tourism industry, Great East Japan Earthquake of 2011, marine leisure use, shellfish gathering, marine ecosystem servicesOpenAcces
