Yearly changes and regional differences in Japanese fish-eating culture in terms of the diversity of major fish species consumed

Abstract

　The diversity of consumption of major fresh fish and shellfish was quantified using the Shannon index for the capital cities of the 47 prefectures in Japan. Geographical characteristics of the diversities were analyzed using global and local Moran's I statistics. The Shannon index shows a downward trend for Japan as a whole between 2000 and 2017. The result of the Global Moran's I statistics shows a downward trend in the concentration of cities with high or low diversity in specific regions. The Local Indicator of Spatial Association (LISA) cluster map, in which the result of local Moran's I statistics is mapped, shows that 11 cities in the Kansai and Setouchi regions are hot-spots of diversity (i.e., a wide variety of fish species are usually consumed in households), while 6 cities (Shizuoka, Kofu, Maebashi, Nagano, Aomori and Sapporo) are cold-spots with low diversity.