|Scientific Name:||Bulweria fallax Jouanin, 1955|
|Taxonomic Source(s):||del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.|
|Red List Category & Criteria:||Near Threatened ver 3.1|
|Reviewer(s):||Butchart, S. & Symes, A.|
|Contributor(s):||Nisbet, I., Clarke, R., Campbell, O. & Bretagnolle, V.|
|Facilitator/Compiler(s):||Anderson, O., Benstead, P., Calvert, R., Taylor, J., Symes, A., Moreno, R.|
This species is listed as Near Threatened because it is suspected to have a moderately small range and almost qualifies for a threatened listing under criteria B2ab(iii,v) and D2. If this was found to be in decline or smaller than suspected, the species may qualify for uplisting to a higher threat category.
|Previously published Red List assessments:|
Bulweria fallax is a poorly known species of the north-west Indian Ocean, occurring widely offshore in the Arabian Sea and Gulfs of Aden and Oman, where it is often the commonest pelagic seabird (Porter et al. 1996), although there are no numerical estimates of total population size or trend. It occurs commonly east of 58°E in the Arabian Sea as far as the Maldive Ridge, regularly east to southern India and Sri Lanka, and regularly, albeit at low densities, to the eastern Indian Ocean in the Bay of Bengal and off north-western Australia (Van den Berg et al. 1991, Ryan et al. 2013, Lavers et al. 2014). During the summer monsoon (May-September) it congregates off the Socotra archipelago (Yemen), where a breeding colony of at least c.50 pairs was recently discovered (Taleb 2002) and where c.3,000 pairs are now estimated to nest locally on mainland cliffs (Al Saghier et al. unpublished), and also off the Halaaniyaat islands (southern Oman), where it may nest (or on the Arabian mainland adjacent) (Gallagher 1985). In recent years, work in UAE waters of the Gulf of Oman has revealed erratic influxes of up to 600 birds in Sept – Dec; the species is either very rare or absent for much of the rest of the year. Similar sea-cliffs within its range on the coast of Somalia deserve investigation for breeding colonies (PERSGA/GEF 2003). A population of unidentified Bulweria petrels, most likely B. fallax, was discovered around Comoro archipelago (Shirihai et al. 2015), with most birds being in active moult, but not all. These individuals, however, show plumage characteristics that do not match with B. fallax.
Native:Oman; Somalia; Yemen
Vagrant:Australia; Djibouti; Indonesia; Kenya; Maldives; Mozambique; Saudi Arabia; Seychelles; United Arab Emirates
Present - origin uncertain:British Indian Ocean Territory; India; Iran, Islamic Republic of; Pakistan; Sri Lanka
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||This is not a particularly rare bird at sea, and the total population runs into thousands, if not tens of thousands. Based on this judgement, the population is placed in the range 2,500-9,999 individuals. This equates to 1,667-6,666 mature individuals, rounded here to 1,500-7,000 mature individuals.|
Trend Justification: Observations suggest that the population may be increasing.
|Current Population Trend:||Increasing|
|Habitat and Ecology:||It frequents open sea all-year-round, only approaching land during the breeding season, at dusk and after dark (Taleb 2002, PERSGA/GEF 2003). Its foraging areas are poorly known, but presumably related to highly productive areas of oceanic upwelling (PERSGA/GEF 2003). It flies low, taking food from the surface of sea, probably mainly plankton e.g. fish eggs, ctenophores and polychaete worms (PERSGA/GEF 2003).|
|Continuing decline in area, extent and/or quality of habitat:||Unknown|
|Generation Length (years):||23.9|
|Movement patterns:||Full Migrant|
|Congregatory:||Congregatory (and dispersive)|
|Major Threat(s):||Seabirds, including B. fallax, were formerly exploited for food and medicinal use (at a subsistence level [Al-Saghier et al. 2000]) on the Halaaniyaat islands (Gallagher 1985) and Socotra (Al-Saghier et al. 2000, Porter et al. in prep.), but this practice apparently no longer occurs due to the availability of cheap poultry and the danger of climbing the cliffs (Taleb 2002). Non-native predators (e.g. rats and cats) are probably a limiting factor (Al-Saghier et al. 2000), although their impact on the Socotran subpopulation may have stabilised long ago, given that Socotra has been inhabited for at least 2,000 years and these mammals are likely to have been present since antiquity. Marine oil-spills are a potential threat.|
Conservation Actions Underway
No actions are currently known. Conservation Actions Proposed
Devise methods for the estimation of the population size. Design and implement regular surveys for population monitoring. Search for other breeding colonies on the coast of Somalia, as and when this is feasible. Enforce measures to prevent and mitigate oil spills. Investigate the impact of introduced predators.
|Amended reason:||Edited: Geographic Range, Threats and Countries of Occurrence. Added references and also added new Contributors and a new Compiler.|
|Citation:||BirdLife International. 2017. Bulweria fallax. (amended version published in 2016) The IUCN Red List of Threatened Species 2017: e.T22698136A112442216.Downloaded on 24 October 2017.|
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