Data Zone
Taxonomic note
Saundersilarus saundersi (del Hoyo and Collar 2014) was previously placed in the genus Larus.
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 |
|---|---|---|
| - | - | A3cde+4cde |
| Year | Category | Criteria |
|---|---|---|
| 2018 | Vulnerable | A3cde+4cde |
| 2016 | Vulnerable | A3cde+4cde |
| 2012 | Vulnerable | A3cde+4cde |
| 2010 | Vulnerable | A3c |
| 2008 | Vulnerable | A3c |
| 2006 | Vulnerable | |
| 2004 | Vulnerable | |
| 2000 | Vulnerable | |
| 1996 | Endangered | |
| 1994 | Endangered | |
| 1988 | Threatened |
| Migratory status | full migrant | Forest dependency | does not normally occur in forest |
| Land-mass type |
continent |
Average mass | - |
| Estimate | Data quality | |
|---|---|---|
| Extent of Occurrence (breeding/resident) | 531,000 km2 | medium |
| Extent of Occurrence (non-breeding) | 2,670,000 km2 | medium |
| Number of locations | 11-100 | - |
| Severely fragmented? | no | - |
| Estimate | Data quality | Derivation | Year of estimate | |
|---|---|---|---|---|
| Population size | 14400 mature individuals | medium | estimated | 2008 |
| Population trend | decreasing | poor | suspected | 1999-2034 |
| Rate of change over the past 10 years/3 generations (longer of the two periods) | 10-19% | - | - | - |
| Rate of change over the future 10 years/3 generations (longer of the two periods) | 30-49% | - | - | - |
| Rate of change over the past & future 10 years/3 generations (longer of the two periods) | 30-49% | - | - | - |
| Generation length | 11.5 years | - | - | - |
| Number of subpopulations | 2-100 | - | - | - |
Population justification: A population estimate of 14,400 mature individuals has been derived from analysis of records and surveys by BirdLife International (2011). This is roughly equivalent to 21,000-22,000 individuals in total.
Trend justification: The species's population is presumed to be declining in line with the rate of habitat loss owing to land reclamation, which is anticipated to increase in the near future. Studies at specific sites have shown declines, for example a drop from over 900 individuals to 575 in the last 15 years at Yancheng National Nature Reserve (Jiang et al. 2010).
| Country/Territory | Presence | Origin | Resident | Breeding visitor | Non-breeding visitor | Passage migrant |
|---|---|---|---|---|---|---|
| China (mainland) | extant | native | yes | |||
| Hong Kong (China) | extant | native | yes | |||
| Japan | extant | native | yes | |||
| Macao (China) | extant | native | yes | |||
| North Korea | extant | native | yes | |||
| Russia | extant | native | ||||
| Russia (Asian) | extant | native | ||||
| South Korea | extant | native | yes | |||
| Taiwan, China | extant | native | yes | |||
| Vietnam | extant | native | yes |
| Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
|---|---|---|---|
| Marine Intertidal | Salt Marshes (Emergent Grasses) | major | breeding |
| Marine Neritic | Estuaries | major | non-breeding |
| Altitude | Occasional altitudinal limits |
| Threat (level 1) | Threat (level 2) | Impact and Stresses | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Agriculture & aquaculture | Annual & perennial non-timber crops - Agro-industry farming | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Slow, Significant Declines | Low Impact: 5 | ||||||
|
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| Agriculture & aquaculture | Marine & freshwater aquaculture - Industrial aquaculture | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Rapid Declines | Medium Impact: 7 | ||||||
|
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| Biological resource use | Fishing & harvesting aquatic resources - Unintentional effects: (subsistence/small scale) [harvest] | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Negligible declines | Low Impact: 4 | ||||||
|
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| Biological resource use | Hunting & trapping terrestrial animals - Intentional use (species is the target) | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
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| Energy production & mining | Oil & gas drilling | Timing | Scope | Severity | Impact | ||||
| Ongoing | Minority (<50%) | Negligible declines | Low Impact: 4 | ||||||
|
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| Invasive and other problematic species, genes & diseases | Invasive non-native/alien species/diseases - Spartina alterniflora | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
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| Residential & commercial development | Commercial & industrial areas | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
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| Residential & commercial development | Housing & urban areas | Timing | Scope | Severity | Impact | ||||
| Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
| Purpose | Scale |
|---|---|
| Food - human | subsistence, national |
| Pets/display animals, horticulture | subsistence, national |
Recommended citation
BirdLife International (2024) Species factsheet: Saunders's Gull Saundersilarus saundersi. Downloaded from
https://datazone.birdlife.org/species/factsheet/saunderss-gull-saundersilarus-saundersi on 23/11/2024.
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 23/11/2024.