This taxon is Not Recognised as a species by BirdLife International.
Hydrobates castro (del Hoyo and Collar 2014) was previously placed in the genus Oceanodroma. Oceanodroma castro (Sibley and Monroe 1990, 1993) was previously split into O. castro and O. monteiroi following Bolton et al. (2008).
BirdLife International (2018) Species factsheet: Hydrobates castro. Downloaded from http://www.birdlife.org on 10/12/2018. Recommended citation for factsheets for more than one species: BirdLife International (2018) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 10/12/2018.