• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2016	Near Threatened	C2a(i)
2012	Near Threatened	C2a(i)
2009	Near Threatened	C2a(i)
2008	Vulnerable
2007	Vulnerable
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
1988	Threatened

Migratory status	full migrant	Forest dependency	does not normally occur in forest
Land-mass type	continent shelf island	Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	3,190,000 km2	medium
Extent of Occurrence (non-breeding)	535,000 km2	medium
Number of locations	11-100	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	10000-15000 mature individuals	medium	estimated	2008
Population trend	decreasing	medium	suspected	1998-2009
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)	10-19%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	10-19%	-	-	-
Generation length	3.7 years	-	-	-
Number of subpopulations	2-100	-	-	-

Population justification: Survey work in Nanjishan National Nature Reserve has estimated a population of c.1,500 pairs in the reserve and at least 5,000 pairs around the lake as a whole (X. Huang et al. in litt. 2007), giving a global population exceeding 10,000 mature individuals but likely below 15,000.

Trend justification: The population is suspected to be declining as a result of habitat degradation and conversion in both breeding and wintering areas.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
China (mainland)	extant	native	yes
Japan	extant	native	yes
Mongolia	extant	native			yes
Russia	extant	native		yes
Russia (Asian)	extant	native		yes
South Korea	extant	native			yes

Country/Territory	IBA Name
China (mainland)	Chongming Dongtan Nature Reserve
China (mainland)	Dongting Hu wetlands
China (mainland)	Eastern tidal flat of Nanhui
China (mainland)	Longfeng Wetland Nature Reserve
China (mainland)	Poyang Hu wetlands
China (mainland)	Shuangtai (Shuangtaizi) Estuary and Inner Gulf of Liaodong
China (mainland)	Yalu Jiang Estuary
China (mainland)	Zhalong Nature Reserve
Japan	Hachirogata
Japan	Hotokenuma, Lake Ogawara and nearby lakes
Japan	Iwakigawa river, Lake Jusanko
Japan	Lake Kasumigaura, Ukisima
Japan	Tonegawa floodplain
Mongolia	Mongol Daguur

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Wetlands (inland)	Bogs, Marshes, Swamps, Fens, Peatlands	major	breeding
Wetlands (inland)	Bogs, Marshes, Swamps, Fens, Peatlands	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		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Agro-industry grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Gathering terrestrial plants - Unintentional effects (species is not the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Rapid Declines		Medium Impact: 6
		Stresses Reduced reproductive success, Species mortality
Natural system modifications	Dams & water management/use - Abstraction of surface water (agricultural use)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Residential & commercial development	Commercial & industrial areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion, Reduced reproductive success, Species mortality

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Recommended citation
BirdLife International (2024) Species factsheet: Marsh Grassbird Helopsaltes pryeri. Downloaded from https://datazone.birdlife.org/species/factsheet/marsh-grassbird-helopsaltes-pryeri on 22/11/2024.
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 22/11/2024.