The site was identified as important in 2014 because it was regularly supporting significant populations of the species listed below, meeting ('triggering') IBA criteria.Populations meeting IBA criteria ('trigger species'):
|Species||Current IUCN Red List Category||Season||Year(s)||Population estimate at site||IBA criteria met|
|Weka Gallirallus australis||VU||resident||-||present||A1|
|Yellow-eyed Penguin Megadyptes antipodes||EN||resident||1932-1990||40-66 breeding pairs||A1, A4ii|
|Sooty Shearwater Ardenna grisea||NT||breeding||2013||100,000-499,999 breeding pairs||A4ii|
|Stewart Island Shag Leucocarbo chalconotus||VU||breeding||1911-2011||384-922 breeding pairs||A1, A4i|
|A4iii Species group - seabirds||n/a||-||-||100,000-499,999 breeding pairs||A4iii|
The current IUCN Red List category may differ from that which was valid at the time of IBA criteria assessment (2014).
|Protected area (PA)||PA designation||PA area (ha)||Relationship of PA with IBA||Overlap of PA with IBA (ha)|
|Whero Rock||Nature Reserve||1||protected area overlaps with site||0|
|Nature Reserve - Bench Island||Nature Reserve||176||protected area overlaps with site||176|
|Habitat (IUCN level 1)||Habitat detail||Extent (% of site)|
BirdLife International (2023) Important Bird Area factsheet: Northern Titi Muttonbird Islands. Downloaded from http://datazone.birdlife.org/site/factsheet/northern-titi-muttonbird-islands-iba-new-zealand on 28/09/2023.