2014 Volume 80 Issue 1 Pages 12-16
After the Great East Japan Earthquake in 2011, about 40,000 people out-migrated from the disaster-stricken areas of Iwate, Miyagi, and Fukushima prefectures. More females than males out-migrated, probably because females tended to fear the potential health hazards of radioactive leakage. In this study, we evaluated the impact of these migrations following the disaster on the sex ratio of the working-age population of all prefectures in Japan. We used the vital statistics in 2012 and 2010 as parameters that were and were not affected by the disaster, respectively. We estimated the future demographic structure using the demographic indices in 2010 and 2012. This analysis revealed that this disaster-induced migration will decrease and increase the sex ratio in the eastern and western parts of Japan, respectively, in 2032. In the disaster-stricken areas, the percentage of males increased in Miyagi and the percentage of females decreased in Fukushima, resulting in an increased sex ratio in both prefectures. Sex-specific migration after the disaster could result in geographical disparity of the sex ratio in Japan.