Data Zone
Taxonomic note
Puffinus bryani (del Hoyo and Collar 2014) was first described by Pyle et al. (2011).
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.
| Critically Endangered | Endangered | Vulnerable |
|---|---|---|
| C2a(i,ii) | C2a(i,ii); D | C2a(i,ii); D1 |
| Year | Category | Criteria |
|---|---|---|
| 2018 | Critically Endangered | C2a(i,ii) |
| 2016 | Critically Endangered | C2a(i,ii) |
| 2015 | Critically Endangered | C2a(i,ii) |
| 2014 | Critically Endangered | C2a(i,ii) |
| 2012 | Not Recognised | |
| 2008 | Not Recognised | |
| 2004 | Not Recognised | |
| 2000 | Not Recognised | |
| 1994 | Not Recognised | |
| 1988 | Not Recognised |
| Migratory status | full migrant | Forest dependency | low |
| Land-mass type | Average mass | - |
| Estimate | Data quality | |
|---|---|---|
| Extent of Occurrence (breeding/resident) | 3,110,000 km2 | |
| Severely fragmented? | no | - |
| Estimate | Data quality | Derivation | Year of estimate | |
|---|---|---|---|---|
| Population size | 50-249 mature individuals | poor | estimated | 2014 |
| Population trend | decreasing | - | suspected | - |
| Number of subpopulations | 1 | - | - | - |
| Percentage of mature individuals in largest subpopulation | 100% | - | - | - |
Population justification: The species's population size has not been quantified, but given its apparent rarity it is thought to have an extremely small population, probably numbering fewer than 250 mature individuals. The population is therefore placed in the band 50-249 mature individuals, assumed to equate to a total population of c.70-380 individuals.
Trend justification: The population is inferred to be in decline owing mainly to predation by introduced rats (Kawakami et al. 2012, Fjeldså 2013).
| Country/Territory | Presence | Origin | Resident | Breeding visitor | Non-breeding visitor | Passage migrant |
|---|---|---|---|---|---|---|
| Japan | extant | native | yes | yes | ||
| United States Minor Outlying Islands (to USA) | extant | native | yes | |||
| USA | extant | native | yes |
| Country/Territory | IBA Name |
|---|---|
| Japan | Chichijima islands-Marine |
| Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
|---|---|---|---|
| Marine Coastal/Supratidal | Sea Cliffs and Rocky Offshore Islands | major | breeding |
| Marine Neritic | Pelagic | major | resident |
| Altitude | Occasional altitudinal limits |
| Threat (level 1) | Threat (level 2) | Impact and Stresses | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Invasive and other problematic species, genes & diseases | Invasive non-native/alien species/diseases - Rattus rattus | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
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| Pollution | Excess energy - Light pollution | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Unknown | Unknown | ||||||
|
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Recommended citation
BirdLife International (2024) Species factsheet: Bryan's Shearwater Puffinus bryani. Downloaded from
https://datazone.birdlife.org/species/factsheet/bryans-shearwater-puffinus-bryani on 22/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/12/2024.