VU
Papyrus Yellow Warbler Calamonastides gracilirostris



Taxonomy

Taxonomic note
Calamonastides gracilirostris and C. bensoni (del Hoyo and Collar 2016) were previously lumped as Chloropeta gracilirostris following Dowsett and Forbes-Watson (1993) and Sibley and Monroe (1990, 1993).

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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - A2c+3c+4c

Red List history
Year Category Criteria
2016 Vulnerable A2c+3c+4c
Species attributes

Migratory status not a migrant Forest dependency Does not normally occur in forest
Land mass type Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 235,000 medium
Number of locations 11-100 -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 10000-19999 poor estimated 2014
Population trend Decreasing medium 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 - - -
Largest subpopulations 1-89 - - -
Generation length (yrs) 3.6 - - -

Population justification: Maclean et al. (2014) estimated the population to be 90,000 adults, assuming 100% occupancy of habitat. Assuming instead that only a proportion (20%) of its habitat is inhabited then the population size may in fact be nearer 18,000 mature individuals. This would fit in the range of 10,000-19,999 mature individuals.

Trend justification: This species's population is suspected to be declining in line with habitat loss and degradation within its range. Rates of decline in this species have been estimated by assuming that the relationship between habitat variables and density/occurrence were the same between data from 1999-2001 compared to 1984-1987 (Maclean et al. 2014). This gave an estimate of a decline over 3 generations of c.35% (80% CI: 15.21-40.15%) in the Albertine Rift population (Maclean et al. 2014). For the Kenyan population, declines were estimated at c.92% (80% CI: 42.40-96.07%), and future declines in this species were stated as likely to be >80% (Maclean et al. 2014). While declines over the past 3 generations may not be the same as that over the modelled time period, declines over 3 generations are still suspected to have been large and ongoing but the global rate of decline is unlikely to exceed 50% over 3 generations. However, the decline would fall in the range of 30-49%.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Burundi N Extant Yes
Congo, The Democratic Republic of the N Extant Yes
Kenya N Extant Yes
Rwanda N Extant Yes
Tanzania N Extant Yes
Uganda N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Wetlands (inland) Bogs, Marshes, Swamps, Fens, Peatlands major resident
Altitude 900 - 2050 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder 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 - Small-holder grazing, ranching or farming Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Gathering terrestrial plants - Unintentional effects (species is not the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Named species - Eichhornia crassipes Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation
Natural system modifications Fire & fire suppression - Trend Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation
Residential & commercial development Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2019) Species factsheet: Calamonastides gracilirostris. Downloaded from http://www.birdlife.org on 27/03/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 27/03/2019.