Red List Category
for more information about the Red List categories and criteria
Justification of Red List category
This species is listed as Endangered because it has an extremely small population. It has significantly increased over the last 20 years, probably owing to intensive conservation efforts
. However, even on islands free from mammalian predators, population sizes fluctuate, with numbers on one island undergoing a possible long-term decline.
50-249 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 -- Marine biome