Red List Category
for more information about the Red List categories and criteria
Justification of Red List category
The species is classified as Vulnerable because it has a very small range: it nests at just three known sites, with possibly over 95% of all known breeding birds concentrated at one cave. Overall population trends are unclear. If contraction of its breeding range continues, or populations are shown to be undergoing a continuous decline owing to a decrease in the number of nest-caves, perhaps compounded by the continuing decline in quality of marshy feeding areas, it should be uplisted to Endangered.
1700-2000 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 - Afrotropical - realm
IUCN Ecosystem -- Freshwater biome
IUCN Ecosystem -- Terrestrial biome