CR
Chinese Crested Tern Thalasseus bernsteini



Taxonomy

Taxonomic note
Thalasseus bernsteini (del Hoyo and Collar 2014) was previously placed in the genus Sterna.

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
C2a(i,ii); D B2ab(iii,v); C2a(i,ii); D B2ab(iii,v); C2a(i,ii); D1+2

Red List history
Year Category Criteria
2016 Critically Endangered C2a(i,ii); D
2015 Critically Endangered C2a(i,ii); D
2013 Critically Endangered C2a(i,ii); D
2012 Critically Endangered C2a(i,ii);D
2010 Critically Endangered C2a(ii); D1
2009 Critically Endangered B1a+b(iii); C2a(ii); D1
2008 Critically Endangered
2004 Critically Endangered
2000 Critically Endangered
1996 Critically Endangered
1994 Critically 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 284 g
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 114,000 medium
Extent of Occurrence non-breeding (km2) 4,370,000 medium
Extent of Occurrence breeding/resident (km2) 60
Extent of Occurrence non-breeding (km2) 6
Number of locations 4 -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 30-49 poor estimated 2013
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) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations 1 - - -
Largest subpopulations 100 - - -
Generation length (yrs) 11 - - -

Population justification: The number of breeding adults varies each year, ranging from 12 in 2012 to at least 43 in 2014. Given this the total number of mature individuals is likely to number fewer than 50, and perhaps most likely 30-49 (S. Chan in litt. 2013).

Trend justification: Repeat surveys at the two known breeding sites since 2003 have shown an overall decrease in the number of breeding pairs.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
China (mainland) N Extant Yes
Indonesia N Extant Yes
Malaysia N Extant Yes
Philippines N Extant Yes
South Korea N Extant Yes
Taiwan (China) N Extant Yes
Thailand N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
China (mainland) Chongming Dongtan Nature Reserve
China (mainland) Jiushan Islands Nature Reserve
China (mainland) Min Jiang Estuary
Malaysia Bako-Buntal Bay
Philippines Manila Bay
Taiwan (China) Matsu (Mazu) Islands Tern Refuge

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Marine Coastal/Supratidal Coastal Brackish/Saline Lagoons/Marine Lakes major non-breeding
Marine Intertidal Mud Flats and Salt Flats major resident
Marine Intertidal Sandy Shoreline and/or Beaches, Sand Bars, Spits, Etc major resident
Marine Intertidal Shingle and/or Pebble Shoreline and/or Beaches major resident
Marine Neritic Pelagic major non-breeding
Marine Neritic Subtidal Sandy-Mud major resident
Altitude   Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Fishing & harvesting aquatic resources - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Unknown Slow, Significant Declines Unknown
Stresses
Species disturbance, Species mortality
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 mortality
Climate change & severe weather Other impacts Timing Scope Severity Impact
Ongoing Majority (50-90%) Very Rapid Declines High Impact: 8
Stresses
Reduced reproductive success
Human intrusions & disturbance Work & other activities Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance
Pollution Industrial & military effluents - Type Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Indirect ecosystem effects
Residential & commercial development Commercial & industrial areas Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem degradation, Ecosystem conversion

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Food - human - - Non-trivial Recent

Recommended citation
BirdLife International (2017) Species factsheet: Thalasseus bernsteini. Downloaded from http://www.birdlife.org on 16/12/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/12/2017.