This is another reply to Cathy Wisel's request for information on birding Japan in the winter. Several years ago we did a winter birding trip with Zegrahm Expeditions with Mark Brazil. Mark wrote the book A Field Guide to the Birds of East Asia (2009), as well as several other books on Japan. He lives on Hokkaido and works for several companies including Victor Emanuel Nature Tours. Here is a link to his web site:
https://www.japannatureguides.com/mark-brazil--zegrahm-expeditions/ This link includes links to 4 videos my wife Dory and I put together on this trip. Explore his web site for lots in information on birding Japan and consider contacting him for more information.
Ray Hamlyn
xtenter at comcast.net