NT
White-tailed Cisticola Cisticola anderseni



Taxonomy

Taxonomic note
This long-known but only recently described (Fjeldså et al. 2021) species is a member of a group of eight species variously labelled ‘marsh’ and ‘streak-backed marsh’ cisticolas, the others being C. galactotes, C. luapula, C. haematocephalus, C. marginatus and C. lugubris, all of which replace each other across Africa’s savanna regions, plus the more local C. pipiens and C. carruthersi. White-tailed Cisticola is smaller and duller than other members of its group, with a dull wood-brown (vs brighter rufous) wing-panel, a white outer edge of the outertail-feather and more prominent white tips to the rectrices (except the two central feathers) contrasting with a broad, black subterminal band. Its song differs markedly as well, consisting of a rapidly repeated phrase of 1?4 (usually 2?3) notes at varying pitch, ‘chi-chi-chi’ (high-pitched) or ‘keek-kuck’ (low-pitched), one note usually less modulated than the other. The species is genetically closest to Coastal Cisticola C. haematocephalus with a 4.31% sequence divergence in the ND2 gene. Monotypic.

Taxonomic source(s)
Handbook of the Birds of the World and BirdLife International. 2022. Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 7. Available at: https://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v7_Dec22.zip.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2022 Near Threatened A3c+4c; B1b(iii)
2016 Not Recognised
2012 Not Recognised
2008 Not Recognised
2004 Not Recognised
2000 Not Recognised
1994 Not Recognised
1988 Not Recognised
Species attributes

Migratory status not a migrant Forest dependency does not normally occur in forest
Land-mass type Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 7,800 km2
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 20000-100000 mature individuals poor estimated 2022
Population trend decreasing - suspected 2021-2031
Rate of change over the past 10 years/3 generations (longer of the two periods) 10-25% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 20-29% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 20-29% - - -
Generation length 2.6 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: The species is described as the commonest cisticola within the Kilombero valley. Jones and John (2008) recorded it at 14 of 15 surveyed localities and in 81% of 159 point counts,  while Rannestad et al. (2015) recorded 177 during surveys along a 60 km river transect. The density has been assessed at different times of year and in different habitats within the Kilombero riparian zone (Rannestad et al. 2015). Highest densities were recorded in both grass-bush habitat and reeds in June (during the highest water levels), with 31.3 ± 6.7 individuals per km2, in each habitat (Rannestad et al. 2015). These values are considered likely to related to mature individuals given that this likely the peak breeding season and detectability is high due to territorial vocalisation. Densities in other periods were lower, suggesting greater dispersion of individuals, reduced detectability, or seasonal movements out of the surveyed area. All three factors may be operating, given the seasonal flooding of the habitat likely concentrates individuals and may be the trigger for breeding (with resulting increased detectability).
 
The extent of assumed suitable habitat is unclear, even more so than for the sympatric C. bakerorum given that this species may occur in degraded habitat (Fjeldså et al. 2021). Wilson et al. (2017) report 1,515 km2 of wet grassland and reeds in 2016, while Leemhuis et al. (2017) report 2,166 km2 in the 'wetland' land cover class in 2016. Msofe et al. (2019) report an area of 'wetland' (excluding waterbodies) of 261 km2, suggesting considerable inconsistency in the land cover classifications used. With the species using drier habitat as well (Fjeldså et al. 2021), the area of suitable habitat is likely to be considerably larger than the very restricted value for wetland given by Msofe et al. (2019). Hence the population size likely exceeds 10,000 mature individuals: e.g. 31.3 mature individuals per kmacross the habitat extent values of Wilson et al. (2016 and Leemhuis et al. (2019) results in numbers between 47,420 and 67,796 individuals. These values are considered only indicative, given that the area values may not be accurately measuring the species' habitat extent if it does use a wider range of vegetation than C. bakerorum.

The population size is suspected to be declining due to the rate of conversion of wetland vegetation within the Kilombero valley (Wilson et al. 2016, Proswitz et al. 2021). Projecting the most recent rate of wetland grassland loss forwards (estimated in 2004 and 2016: Wilson et al. 2017) indicates the loss of 31% of the remaining vegetation by 2032, and 32% for the ten years between 2023 and 2033. However, as the species has been reported to use areas degraded by grazing, it is likely that the rate of population reduction is lower than this rate of conversion. On a precautionary basis the population is suspected to be declining at a rate between 20-29% over ten years.

Trend justification: The species is associated with the floodplain vegetation of the Kilombero valley, which is being converted to agriculture by a rapidly increasing human population (predicted to double by 2030: Proswitz et al. 2021) at a rate equivalent to at least 25% over the past ten years and in excess of 30% for the ten year period including the present year and for the ten year period commencing 2023 (based on data comparing land classifications over time in Wilson et al. [2017] and Leemhuis et al. [2017]).
This species does not appear to be extremely closely tied to the extent of the natural floodplain vegetation however, and the connection between the rate of habitat loss and the population size of C. anderseni is unclear. On a precautionary basis, given that the level of vegetation conversion is so rapid, it is suspected that there is a corresponding reduction in the population of between 10-25% over the past ten years 20-29% for the current and future ten year periods. Quantifying this is an important part of the monitoring work to be undertaken for the Integrated Management Plan for the Kilombero Valley Ramsar Site over the next decade (Wilson et al. 2017, Ministry of Natural Resources and Tourism 2018).


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Tanzania extant native yes

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

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Aquatic & Marine Artificial/Aquatic - Seasonally Flooded Agricultural Land suitable resident
Grassland Subtropical/Tropical Seasonally Wet/Flooded major resident
Wetlands (inland) Bogs, Marshes, Swamps, Fens, Peatlands suitable resident
Altitude 240 - 305 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Agro-industry farming Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem degradation, Ecosystem conversion
Natural system modifications Dams & water management/use - Abstraction of surface water (agricultural use) Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Ecosystem degradation
Natural system modifications Dams & water management/use - Small dams Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Indirect ecosystem effects

Recommended citation
BirdLife International (2025) Species factsheet: White-tailed Cisticola Cisticola anderseni. Downloaded from https://datazone.birdlife.org/species/factsheet/white-tailed-cisticola-cisticola-anderseni on 07/01/2025.
Recommended citation for factsheets for more than one species: BirdLife International (2025) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 07/01/2025.