
These are species with at least one recorded territory in Russia, not a national checklist: a bird list from eBird or Avibase is more complete. The counts follow recording effort as much as wildlife, so a country with more visitors and more naturalists will show more of both.
The species with the most open occurrence records in Russia, among those a photograph exists for. Most recorded is not most numerous: it rewards animals that are common, conspicuous and live where people go.

Corvus cornix

Turdus pilaris

Larus argentatus

Sterna hirundo

Larus canus

Circus cyaneus

Rana arvalis

Tadorna ferruginea

Fringilla montifringilla

Haematopus ostralegus

Luscinia luscinia

Sitta europaea
The reference database has no regions filed under Russia.
The field guide covers Russia on the map, but none of its species have an entry written for them yet.