The presenter introduce the conditions under which Asian swans survive in temperate zones due to injuries and illnesses. Cygnus cygnus and Cygnus columbianus are migratory birds that originally overwinter at the north and northwest area in Japan, and migrate from the spring breeding season to the subarctic forest or boreal tundra at Siberia in Russia. In rare cases, there are swans that are unable to return to Siberia from their wintering grounds due to contact with high-voltage power lines several tens of meters high, or due to natural diseases and disorders.
Based on cases in Ibaraki and Nagano prefectures in Japan where some swans survived after oversummering for several years, the presenter will consider the conditions for survive under which swans that do not normally oversummer in temperate zones, and will report the contents of the assistance provided by local governments and residents.