Opinions from S. L. Olson and H. F. James 1991
- 'Accipitridae belongs to Falconiformes'
- 'Anatidae belongs to Anseriformes'
- 'Apteribis belongs to Plataleidae'
- 'Apteribis brevis belongs to Apteribis'
- 'Apteribis glenos belongs to Apteribis'
- 'Branta belongs to Anatidae'
- 'Branta hylobadistes belongs to Branta'
- 'Chelychelynechen belongs to Anatidae'
- 'Chelychelynechen quassus belongs to Chelychelynechen'
- 'Circus belongs to Accipitridae'
- 'Circus dossenus belongs to Circus'
- 'Falco albicilla is recombined as Haliaeetus albicilla'
- 'Falco leucocephalus is recombined as Haliaeetus leucocephalus'
- 'Geochen belongs to Anatidae'
- 'Geochen rhuax belongs to Geochen'
- 'Grallistrix belongs to Strigidae'
- 'Grallistrix auceps belongs to Grallistrix'
- 'Grallistrix erdmani belongs to Grallistrix'
- 'Grallistrix geleches belongs to Grallistrix'
- 'Grallistrix orion belongs to Grallistrix'
- 'Haliaeetus belongs to Accipitridae'
- 'Plataleidae belongs to Ciconiiformes'
- 'Porzana belongs to Rallidae'
- 'Porzana keplerorum belongs to Porzana'
- 'Porzana menehune belongs to Porzana'
- 'Porzana ralphorum belongs to Porzana'
- 'Porzana severnsi belongs to Porzana'
- 'Porzana ziegleri belongs to Porzana'
- 'Procellariidae belongs to Procellariiformes'
- 'Ptaiochen belongs to Anatidae'
- 'Ptaiochen pau belongs to Ptaiochen'
- 'Pterodroma belongs to Procellariidae'
- 'Pterodroma jugabilis belongs to Pterodroma'
- 'Rallidae belongs to Gruiformes'
- 'Strigidae belongs to Strigiformes'
- 'Thambetochen belongs to Anatidae'
- 'Thambetochen chauliodous belongs to Thambetochen'
- 'Thambetochen xanion belongs to Thambetochen'