||Cisticola aberdare Lynes, 1930
||Cisticole des Aberdares
||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.
||12-15 cm. Medium-sized, grass-dwelling warbler. Well-streaked buff-and-black on upperparts. Uniform buffy underparts. Similar spp. Stout Cisticola C. robustus has rufous nape and hindneck and slightly longer tail. Voice Mixture of peeuu tew tew and shorter trills. Mostly silent except when breeding. Hints Upland moorland above 3,000 m in Aberdare Mountains, and grassland above 2,300 m around Molo and Mau Narok.
|Red List Category & Criteria:
||Adhiambo, P., Bennun, L. & Gatarabirwa, L.
||Benstead, P., Ekstrom, J., Evans, T., Shutes, S., Starkey, M., Symes, A., Taylor, J. & Westrip, J.
Within this species's very small range, much of its habitat is probably being lost rapidly and becoming severely fragmented, owing to agricultural development and intensified livestock production. A re-assessment of its extent of occurrence using a Minimum Convex Polygon means it no longer meets the threshold for listing as Endangered, but it the newly calculated range size and the rapid rate of decline mean that it still warrants listing as Vulnerable.
|Previously published Red List assessments:|
- 2016 – Endangered (EN)
- 2012 – Endangered (EN)
- 2008 – Endangered (EN)
- 2004 – Endangered (EN)
- 2000 – Endangered (EN)
- 1994 – Lower Risk/least concern (LR/lc)
- 1988 – Lower Risk/least concern (LR/lc)
|Range Description:||Cisticola aberdare is found in central Kenya where it is locally common in suitable habitat (Zimmerman et al. 1996) on both sides of the Rift Valley, at Molo, Mau Narok and the Aberdare Mountains. Recent studies confirm the presence of the species in very low numbers at 2,400 m-2,700 m on the Kinangop Plateau, at the base of the Aberdare Mountains (L. Bennun in litt. 1999, 2000, P. Adhiambo in litt. 2008). Simple extrapolation of density figures in the Aberdares indicates a population there of c.50,000 birds (L. Bennun in litt. 1999, 2000, W. Gatarabirwa in litt. 1999, 2000). In 2000, 1,750 ±60 individuals were estimated at Mau Narok and Molo (P. Adhiambo in litt. 2007). A 2011 survey found the species in fairly good numbers in suitable habitat, with 137 individuals counted within an area of 35.6 ha (c4 birds/ha) (Malaki et al. 2011), however the rapid loss of grassland at Mau Narok and Molo, which now covers less than a third of the extent estimated in the late 1990s (P. Adhiambo in litt. 2007), suggests that the population is experiencing a rapid, ongoing population decline. |
|♦ Continuing decline in area of occupancy (AOO):||Yes|
|♦ Extreme fluctuations in area of occupancy (AOO):||No||♦ Estimated extent of occurrence (EOO) - km2:||5500|
|♦ Continuing decline in extent of occurrence (EOO):||Yes||♦ Extreme fluctuations in extent of occurrence (EOO):||No|
|♦ Number of Locations:||11-100||♦ Continuing decline in number of locations:||Yes|
|♦ Extreme fluctuations in the number of locations:||No||♦ Lower elevation limit (metres):||2300|
|♦ Upper elevation limit (metres):||3700|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Simple extrapolation of density figures in the Aberdares indicates a population there of c.50,000 birds (L. Bennun in litt. 1999, 2000, W. Gatarabirwa in litt. 1999, 2000), thus the population is placed in the range bracket for 50,000-999,999 individuals.|
Trend Justification: The rapid loss of grassland at Mau Narok and Molo, which now covers less than a third of the extent estimated in the late 1990s (P. Adhiambo in litt. 2007), suggests that the population is experiencing a rapid population decline.
|Current Population Trend:||Decreasing|
|♦ Continuing decline of mature individuals:||Yes|
|♦ Extreme fluctuations:||No||♦ Population severely fragmented:||Yes|
|♦ No. of subpopulations:||2-100||♦ Continuing decline in subpopulations:||Unknown|
|♦ Extreme fluctuations in subpopulations:||No||♦ All individuals in one subpopulation:||No|
In the Mau Narok/Molo grasslands, this species is probably threatened by rapid habitat loss and fragmentation due to expanding cultivation and intensified livestock production (Keith et al. 1992, Lens et al. 1996, P. Adhiambo in litt. 2007). Many areas of grassland, especially in Mau Narok, are subjected to burning by farmers to improve grazing quality, often repeatedly with the onset of the rainy season, which may destroy grass tussocks used for nesting (P. Adhiambo in litt. 2007). Fires in the dry season (late January to March), possibly started by illegal honey-gatherers, sometimes burn large areas of moorland in the Aberdare National Park, and may be a further threat, given that densities are much lower in recently burned areas (L. Bennun in litt. 1999, 2000, W. Gatarabirwa in litt. 1999, 2000). The nests may be vulnerable to damage by livestock and tractors (Eshiamwata and Karimi 2003, P. Adhiambo in litt. 2007).