Clements/eBird and IOC split the Bean Goose into two species, although Carboneras & Kirwan (2019) make a good case for the traditional approach of only one species, an approach also adopted by H&M4. Regardless of taxonomic position, these birds are representative of the large, long-billed subspecies middendorffii. These geese were formerly abundant in Japan but have declined in recent years because of over-hunting and reclamation of habitat in places like Tokyo Bay. These birds may be distinguished from the similar but smaller Tundra Bean-Goose by their longer bill and sloping forehead. They are considered "near threatened" in Japan with a wintering population of about 9,000 birds. Photography was made difficult by the requirement at this reserve that vehicles are not allowed to stop near the birds. Viewing was only allowed at a special viewing site a considerable distance from the flock.
Canon PowerShot SX60 (top two)
Digiscoped with Panasonic Lumix LX5 | Nikon Fieldscope III | 30X hand-held no adapter (bottom)
References:
Carboneras, C. & Kirwan, G.M. (2019). Bean Goose (Anser fabalis). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52811 on 29 March 2019).