Howland Island


IBA Justification

The site was identified as internationally important for bird conservation in 2012 because it was regularly supporting significant populations of the species listed below, meeting ('triggering') IBA criteria.

Populations meeting IBA criteria ('trigger species') at the site:
Species Red List Season (year/s of estimate) Size IBA criteria
Red-tailed Tropicbird Phaethon rubricauda LC breeding (1973–2007) 496 birds A4ii
Lesser Frigatebird Fregata ariel LC breeding (1973–2007) 3,850 birds A4ii
Masked Booby Sula dactylatra LC breeding (1973–2007) 3,763 birds A4ii
Bristle-thighed Curlew Numenius tahitiensis NT non-breeding (1973–2007) max 62 birds A1
Sooty Tern Onychoprion fuscatus LC breeding (1973–2007) 200,000 birds A4i
A4iii Species group - waterbirds n/a breeding (1973–2007) 203,011 birds A4iii

IBA Conservation

Ideally the conservation status of the IBA will have been checked regularly since the site was first identified in 2012. The most recent assessment (2012) is shown below.

IBA conservation assessment
Year of assessment State Pressure Response
2012 good medium high
Whole site assessed? State assessed by Accuracy of information
yes population medium

State (condition of the trigger species' populations)
Species Actual vs Reference (units) % remaining Result
Red-tailed Tropicbird Phaethon rubricauda 496 / 496 (birds) 100 not assessed
Lesser Frigatebird Fregata ariel 3,850 / 3,850 (birds) 100 not assessed
Masked Booby Sula dactylatra 4,500 / 3,763 (birds) 100 good
Bristle-thighed Curlew Numenius tahitiensis 62 / 62 (birds) 100 not assessed
A4iii Species group - waterbirds 153,061 / 153,061 (birds) 100 not assessed

Pressure (threats to the trigger species and/or their habitats)
Threat Timing Scope Severity Result
Climate change and severe weather likely in long term (>4 years) whole of popul­ation/area (>90%) slow decline (1–10% over 3 gener­ations) medium

Response (conservation actions taken for the trigger species and/or their habitats)
Designation Planning Action Result
Whole area (>90%) covered by appropriate conservation designation A compre­hensive and appropriate management plan exists that aims to maintain or improve the populations of qualifying bird species Substantive conservation measures are being implemented, but these are not compre­hensive and are limited by resources and capacity high

IBA Protection

Year Protected Area Designation (management category) % coverage of IBA
1974 Howland Island National Wildlife Refuge (Ia) 100
2009 Pacific Remote Islands Marine National Monument (V) 100


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Howland Island (United States Minor Outlying Islands (to USA)). Downloaded from https://datazone.birdlife.org/site/factsheet/howland-island-iba-united-states-minor-outlying-islands-(to-usa) on 25/12/2024.