Page link for differences between the Temminck’s (Japanese) Cormorant, and the Great Cormorant. Links to the helpful paper of Dr. Nial Moores & Nick Lethaby.
Willow vs. Marsh Tits
Page link for helpful differences in identifying between the Willow and Marsh Tits. Links to the great paper by Richard K. Broughton.
Hokkaido’s Eurasian Nuthatches
Page link discussing the new separation of species for the “Siberian Nuthatch” and links to a excellent paper with drawings and bill details for the Eurasian Nuthatches done by Yaroslav A. Red’kin and Maria V. Konovalova of the Zoological Museum of Moscow University. They discuss the whole region beyond Hokkaido as well.