• 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
2021	Near Threatened	C2a(ii)
2018	Near Threatened	C2a(ii)
2016	Least Concern
2012	Least Concern
2009	Least Concern
2008	Least Concern
2004	Least Concern
2000	Lower Risk/Least Concern
1994	Lower Risk/Least Concern
1988	Lower Risk/Least Concern

Migratory status	not a migrant	Forest dependency	low
Land-mass type		Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	970 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	2500-9999 mature individuals	poor	suspected	2018
Population trend	decreasing	-	suspected	-
Generation length	4.3 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The species has been described as common across the island (Fry and Keith 2004; Craig 2018). Yet, a recent survey found the species at only 268 out of 3,056 point counts (Soares 2017). Using population densities estimates for congeners (although these are for continental species), the population size may fall in the range 1,000-2,499 mature individuals. However, this species is gregarious, so multiple individuals can be found at a single point count (Jones and Tye 2006), and island species often occur at higher densities (R. F. de Lima in litt. 2018). Therefore, the population size is very tentatively placed here in the range 2,500-9,999 mature individuals.

Trend justification: The species is tolerant of degraded habitats, so habitat degradation is unlikely to impact this species. However, its tolerance of degraded habitats may bring it into contact with introduced predators such as House Rats (Rattus rattus), but it is highly uncertain whether such predators are having an impact on the species at all. The species is very precautionarily suspected to be declining, but further information could show the species to be stable or even increasing.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
São Tomé e Príncipe	extant	native	yes

Country/Territory	IBA Name
São Tomé e Príncipe	Parque Natural Obô de São Tomé e Zona Tampão
São Tomé e Príncipe	São Tomé lowland forests
São Tomé e Príncipe	São Tomé montane and cloud-forests

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Arable Land	suitable	resident
Artificial/Terrestrial	Plantations	major	resident
Artificial/Terrestrial	Subtropical/Tropical Heavily Degraded Former Forest	suitable	resident
Forest	Subtropical/Tropical Moist Lowland	major	resident
Forest	Subtropical/Tropical Moist Montane	suitable	resident
Savanna	Dry	suitable	resident
Altitude	0 - 1500 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Small-holder farming	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Cercopithecus mona	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Civettictis civetta	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus rattus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Reduced reproductive success, Species mortality

Purpose	Scale
Pets/display animals, horticulture	international

---

Recommended citation
BirdLife International (2024) Species factsheet: Giant Weaver Ploceus grandis. Downloaded from https://datazone.birdlife.org/species/factsheet/giant-weaver-ploceus-grandis on 23/12/2024.
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 23/12/2024.