Justification of Red List Category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Brooke (2004) estimated the global population to number around 500,000 individuals.
The population is suspected to be in decline owing to ongoing threats.
The Black-bellied Storm-petrel has a circumpolar distribution from islands of the Scotia Archipelago, through the southern Indian Ocean to the Antipodes Islands (New Zealand). Outside the breeding season, it migrations north into the subtropical and tropical zones of the Atlantic, Indian and Pacific Oceans, regularly occurring north up to the equator (del Hoyo et al. 1992).
This species rarely occurs on land, except when breeding. It may be associated with cool currents where it feeds on squid and small fish (data lacking). Its breeding season begins in November, when it forms loose colonies on bare rocky slopes, in thick vegetation or peat of offshore islands or stacks. It lays one egg in burrows or rocky crevices (del Hoyo et al. 1992).
A number of White-bellied Storm-petrels are killed each year due to light-induced collisions with boats however, the extent of this seems to be small (Black 2005).
Text account compilers
Butchart, S., Ekstrom, J., Calvert, R., Fjagesund, T., Martin, R., Miller, E., Stuart, A.
BirdLife International (2019) Species factsheet: Fregetta tropica. Downloaded from http://www.birdlife.org on 21/04/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/04/2019.