VU
Saunders's Gull Saundersilarus saundersi



Taxonomy

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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - A3cde+4cde

Red List history
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
Species attributes

Migratory status full migrant Forest dependency Does not normally occur in forest
Land mass type Land-mass type - continent
Average mass -
Distribution

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 531,000 medium
Extent of Occurrence non-breeding (km2) 2,670,000 medium
Number of locations 11-100 -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 14400 medium estimated 2008
Population trend Decreasing poor suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) 30-49 - - -
Decline (10 years/3 generation past and future) 30-49 - - -
Number of subpopulations 2-100 - - -
Percentage in largest subpopulation - - -
Generation length (yrs) 11.5 - - -

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 distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
China (mainland) N Extant Yes
Hong Kong (China) N Extant Yes
Japan N Extant Yes
Macao (China) N Extant Yes
North Korea N Extant Yes
Russia N Extant
Russia (Asian) N Extant
South Korea N Extant Yes
Taiwan, China N Extant Yes
Vietnam N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Vietnam Nghia Hung
Vietnam Thai Thuy
Vietnam Tien Lang
Vietnam An Hai
Vietnam Xuan Thuy
Vietnam Tra Co
China (mainland) Shuangtai (Shuangtaizi) Estuary and Inner Gulf of Liaodong
China (mainland) Yalu Jiang Estuary
China (mainland) Beidaihe
China (mainland) Luan He Estuary
China (mainland) Yellow River Delta Nature Reserve
China (mainland) Yancheng Nature Reserve
China (mainland) Chongming Dongtan Nature Reserve
China (mainland) Poyang Hu wetlands
China (mainland) Yong Jiang Estuary
China (mainland) Taizhou Wan
China (mainland) Yueqing Wan
China (mainland) Xuanmen Wan
China (mainland) Wenzhou Wan
China (mainland) Min Jiang Estuary
China (mainland) Futian
China (mainland) Nanliujiang Hekou
China (mainland) Dongzhaigang
Hong Kong (China) Inner Deep Bay and Shenzhen River catchment area
Japan Kamogawa estuary
Japan Sone tidal flat
Japan Hakata bay
Japan Inner Ariake bay
Japan Hikawa estuary, Shiranui
Japan Kumakawa estuary
Japan Nakatsu and Usa tidal flats
North Korea Taedong River estuary
South Korea Tidal flat area of Yeongjong-do island
South Korea Sihwa-ho lake
South Korea Namyang Bay
South Korea Geum-gang river and estuary
South Korea Asan Bay (including Asan-ho lake and Sapgyo-ho lake)
South Korea Suncheon Bay
South Korea Nakdong-gang estuary
Taiwan, China Hsinchu City Coastal Area
Taiwan, China Kaomei Wetlands
Taiwan, China Tatu Rivermouth Wildlife Refuge
Taiwan, China Hanbao Wetlands
Taiwan, China Tacheng Wetlands
Taiwan, China Aogu Wetlands
Taiwan, China Pohtzi River Estuary
Taiwan, China Budai Wetlands
Taiwan, China Beimen
Taiwan, China Lanyang River Estuary
Taiwan, China Chu'an
Taiwan, China Kinmen National Park
South Korea Tidal flat area of southern Ganghwa-do island
South Korea Cheonsu Bay
South Korea Mangyeong estuary
South Korea Yubu-do island
South Korea Dongjin estuary
Vietnam Tien Hai
Taiwan, China Dapingding and Hsutsuo Harbor
China (mainland) Coastal wetlands of northern Chongming Dao island
China (mainland) Eastern tidal flat of Nanhui
China (mainland) Gongping Dahu Nature Reserve
China (mainland) Hangzhou Wan
China (mainland) Jiuduansha Nature Reserve
Japan Kamogawa estuary - Marine
Japan Kyushu seas (north and west)
China (mainland) Chongming Dongtan Nature Reserve - Marine
China (mainland) Laoting (Daqing He–Shi Jiu Tuo)
China (mainland) Huanghua coast (Cangzhou)
China (mainland) Dongsha shoals
China (mainland) Tiaozini (Dongtai coast)
China (mainland) Rudong coast
China (mainland) Dongling coast
China (mainland) Xinghua Bay
China (mainland) Meizhou Bay
China (mainland) Xiamen coast
China (mainland) Leizhou Bay

Habitats & altitude
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  

Threats & impact
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
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Marine & freshwater aquaculture - Industrial aquaculture Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Ecosystem degradation, Ecosystem conversion, Reduced reproductive success
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
Stresses
Species disturbance, Reduced reproductive success
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
Stresses
Species disturbance, Reduced reproductive success
Energy production & mining Oil & gas drilling Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion
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
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Commercial & industrial areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Food - human - - Non-trivial Recent
Pets/display animals, horticulture - - Non-trivial Recent

Recommended citation
BirdLife International (2022) Species factsheet: Saundersilarus saundersi. Downloaded from http://www.birdlife.org on 07/10/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 07/10/2022.