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.
Critically Endangered | Endangered | Vulnerable |
---|---|---|
- | C2a(i) | C2a(i) |
Year | Category | Criteria |
---|---|---|
2021 | Endangered | C2a(i) |
2016 | Endangered | C2a(i) |
2012 | Endangered | C2a(i) |
2008 | Endangered | C2a(i) |
2004 | Endangered | |
2000 | Endangered | |
1996 | Vulnerable | |
1994 | Vulnerable | |
1988 | Threatened |
Migratory status | not a migrant | Forest dependency | high |
Land-mass type |
continent |
Average mass | - |
Estimate | Data quality | |
---|---|---|
Extent of Occurrence (breeding/resident) | 68,800 km2 | medium |
Severely fragmented? | no | - |
Estimate | Data quality | Derivation | Year of estimate | |
---|---|---|---|---|
Population size | 1000-3500 mature individuals | poor | estimated | 2021 |
Population trend | decreasing | poor | inferred | 2016-2026 |
Rate of change over the past 10 years/3 generations (longer of the two periods) | 1-15% | - | - | - |
Rate of change over the future 10 years/3 generations (longer of the two periods) | 1-15% | - | - | - |
Rate of change over the past & future 10 years/3 generations (longer of the two periods) | 1-15% | - | - | - |
Generation length | 3.46 years | - | - | - |
Number of subpopulations | 5 | - | - | - |
Percentage of mature individuals in largest subpopulation | 1-89% | - | - | - |
Population justification: Based on this species’s apparent rarity, and the scarcity of records, taking the lower quartiles of density estimates of a forest-dwelling congener, the Southern Masked-weaver Ploceus velatus, of 0.59-2 individuals/sqkm (BirdLife Population Density Spreadsheet; Vernon 1985; Dean 1995), and assuming it inhabits 5% of the forest within its range (51,700 sqkm [Global Forest Watch 2021]), the population may fall in the band 1,525-5,170 individuals. This is roughly equivalent to 1,016-3,447 mature individuals rounded here to 1,000-3,500 mature individuals. Furthermore, if it is known from 5 different sites (H. Rainey in litt. 2021), this species may have multiple subpopulations, so it is plausible that there may be <1,000 mature individuals in the largest subpopulation.
Trend justification: This species has a high forest dependency and is therefore inferred to be declining in line with continued habitat loss and degradation (Global Forest Watch 2021; Tchoumbou et al. 2020). During the years 2000-2019, this species's range experienced a 5.2% loss in forest cover (Global Forest Watch 2020). This equates to a loss of 2.9% over 3 generations. Tchoumbou et al. (2020) suggest that overall, the rate of deforestation in Cameroon is higher, at a 1% loss per annum. This would equate to a loss of 10% over 3 generations for this species. During the years 2016-2019, this species's range experienced forest cover loss of 2.2% (Global Forest Watch 2020). Projected forward over 10 years this equates to a loss of 5.7%. If the rate of deforestation suggested by Tchoumbou et al. (2020) continues (at 1% per annum), that would equate to 10% over 10 years. Assuming that the population declines at a similar rate to forest loss, the rate of decline is suspected to fall in the band of 1-15%.
Country/Territory | Presence | Origin | Resident | Breeding visitor | Non-breeding visitor | Passage migrant |
---|---|---|---|---|---|---|
Cameroon | extant | native | yes |
Country/Territory | IBA Name |
---|---|
Cameroon | Mount Cameroon and Mokoko-Onge |
Cameroon | Mount Kupe |
Habitat (level 1) | Habitat (level 2) | Importance | Occurrence |
---|---|---|---|
Forest | Subtropical/Tropical Moist Lowland | major | resident |
Altitude | 0 - 900 m | 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 | ||||
Future | Majority (50-90%) | Rapid Declines | Low Impact: 5 | ||||||
|
|||||||||
Agriculture & aquaculture | Annual & perennial non-timber crops - Scale Unknown/Unrecorded | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
Biological resource use | Logging & wood harvesting - Unintentional effects: (large scale) [harvest] | Timing | Scope | Severity | Impact | ||||
Ongoing | Majority (50-90%) | Slow, Significant Declines | Medium Impact: 6 | ||||||
|
|||||||||
Invasive and other problematic species, genes & diseases | Problematic native species/diseases | Timing | Scope | Severity | Impact | ||||
Unknown | Majority (50-90%) | Unknown | Unknown | ||||||
|
|||||||||
Natural system modifications | Other ecosystem modifications | Timing | Scope | Severity | Impact | ||||
Ongoing | Unknown | Unknown | Unknown | ||||||
|
Recommended citation
BirdLife International (2024) Species factsheet: Bates's Weaver Ploceus batesi. Downloaded from
https://datazone.birdlife.org/species/factsheet/batess-weaver-ploceus-batesi 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.