Red List Category
for more information about the Red List categories and criteria
Justification of Red List category
This species declined very rapidly over the past three generations until the end of the 20th century, thus it qualifies as Endangered. It now has a very small effective population size because intense predation has left many subpopulations with an excess of unpaired males; however, intensive conservation efforts since 1990 that aimed to restore the population to c.1,000 pairs by the year 2020 have resulted in population increases that are more rapid than expected, so this target is set to be raised.
1000 mature individuals
Distribution size (breeding/resident):
Land-mass type - oceanic island - Oceanic islands are islands or island groups that are <200,000 sq km in size and separated from other land masses by >200 m sea depth. Generally Oceanic islands are islands or island groups that are <200,000 sq km in size and separated from other land masses by >200 m sea depth. Generally they have never been connected to a continental area by a land-ridge, and are volcanic in origin.
Realm - Oceanic - realm
IUCN Ecosystem -- Terrestrial biome