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Papyrus Yellow Warbler Chloropeta gracilirostris

Justification
This species is listed as Vulnerable because it is believed to have a small and severely fragmented population, which is suspected to be undergoing a continuing decline owing to drainage and human exploitation of its papyrus-swamp habitat.

Taxonomic source(s)
Dowsett, R. J.; Forbes-Watson, A. D. 1993. Checklist of birds of the Afrotropical and Malagasy regions. Tauraco Press, Li
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.

Identification
14 cm. Medium-sized warbler of swamps. Warm olive-brown to russet above, especially on tail. Yellow below, washed with olive across breast and flanks. Similar spp. Other warblers in swamps are brown, grey and white, rather than yellow-and-green. Voice Melodious, liquid warblings. Hints Most often detected by voice. Most accessible site is at Lake Bunyonyi, Uganda. It occurs singly or in pairs, foraging in the mid and upper levels of papyrus for tiny insects, and perhaps tending to feed over water (Chapin 1953).

Distribution and population
Chloropeta gracilirostris has a severely fragmented range in the Great Lakes region of Africa. The nominate race occurs in western Kenya (Nasirwa and Njoroge 1997), western Uganda (Chapin 1953, J. Lindsell in litt. 1999, D. Pomeroy in litt. 1999) and adjacent areas of Democratic Republic of Congo (DRC) (Chapin 1953), in Rwanda and Burundi extending just into north-west Tanzania (Vande weghe 1981), and it may also occur in unsurveyed areas of west and north-west Tanzania (N. Baker in litt. 1999). The race bensoni is known only from Lake Mweru at the mouth of the Luapula river in Zambia, and also occurs in adjacent swamps in the neighbouring DRC (Maclean 2006). The species can be locally common (Keith and Vernon 1969, Vande weghe 1981), but seems to be scarce in many areas of apparently suitable habitat (although it is easily overlooked).

Population justification
The population is estimated to number 2,500-9,999 mature individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size, and the fact that only a proportion of the estimated Extent of Occurrence is likely to be occupied. This estimate is equivalent to 3,750-14,999 individuals, rounded here to 3,500-15,000 individuals.

Trend justification
This species's population is suspected to be declining in line with habitat loss and degradation within its range. The likely rate of decline, however, has not been estimated.

Ecology
It is found mainly in papyrus-swamps but occasionally in other marshy habitats, especially reeds (Chapin 1953, Nasirwa and Njoroge 1997, Leonard and Beel 1999, P. Leonard in litt. 1999). Its breeding ecology is unknown, but individuals of the nominate race have been recorded in breeding condition between April and June (Chapin 1953, Britton and Harper 1969).

Threats
Its wetland sites are threatened by drainage for the cultivation of crops (Maclean et al. 2003), such as rice (Maclean 2006), and dairy farming (Maclean et al. 2003). Ongoing drainage of Yala Swamp, the most important site in Kenya, will reduce the national area of occupancy by about a third, despite the poor agricultural performance of already drained areas (L. Bennun in litt. 1999). All other papyrus-swamps in Kenya are threatened both by human pressure, owing to an expanding population, and by man-made ecological changes in Lake Victoria itself, including infestation by water hyacinth Eichhornia crassipes (L. Bennun in litt. 1999). This latter problem has caused the collapse of the Lake Victoria fisheries, forcing local people to seek other sources of income (Maclean et al. 2003). Such problems, and a shortage of productive land, create pressure through the encroachment of agriculture and over-harvesting of papyrus for use as fuel or in local crafts (Maclean et al. 2003). Similar problems may affect it in Uganda. In Rwanda, its wetlands are being progressively degraded through cutting and burning of papyrus in the dry season (Kanyamibwa 2001) and the situation is probably similar in Burundi. Its habitat in Zambia may be at risk from fire (Leonard and Beel 1999), while its current status in the DRC is unknown. One site in Kenya is threatened by the expansion of a nearby town (Maclean 2006).

Conservation Actions Underway
Its ecology is being studied at Yala Swamp in Kenya (Nasirwa et al. 2000). In Uganda, there is a substantial area of papyrus within Lake Mburo National Park and part of Lake George is within Queen Elizabeth National Park. Lakes Edward and Bunyonyi, and the Butiaba area on Lake Albert, may be suitable for community-based conservation projects (J. Lindsell in litt. 1999).Conservation Actions Proposed
Assess its current distribution and status throughout its range (L. Bennun in litt. 1999, D. Pomeroy in litt. 1999). Carry out surveys to monitor population trends. Prepare an action plan for the conservation of papyrus-swamp in the Kenyan sector of Lake Victoria (L. Bennun in litt. 1999). Protect Rugezi Swamp in Rwanda (Kanyamibwa 2001). Carry out research to further investigate the uncertain taxonomy of the species, paying particular attention to differences in song (Maclean et al. 2003, Maclean 2006). Monitor rates of wetland destruction and degradation across its range.

Related state of the world's birds case studies

References
Britton, P. L.; Harper, P. F. 1969. Some new distributional records for Kenya. Bulletin of the British Ornithologists' Club 89: 162-165.

Chapin, J. P. 1953. Birds of the Belgian Congo. Bulletin of the American Museum of Natural History 75A, Part 3.

Collar, N. J.; Stuart, S. N. 1985. Threatened birds of Africa and related islands: the ICBP/IUCN Red Data Book. International Council for Bird Preservation, and International Union for Conservation of Nature and Natural Resources, Cambridge, U.K.

Kanyamibwa, S. 2001. Rwanda. In: Fishpool, L.D.C.; Evans, M.I. (ed.), Important Bird Areas in Africa and associated islands: Priority sites for conservation, pp. 703-710. Pisces Publications and BirdLife International (BirdLife Conservation Series No.11), Newbury and Cambridge, UK.

Keith, G. S.; Vernon, C. J. 1969. Bird notes from northern and eastern Zambia. Puku 5: 131-139.

Leonard, P.; Beel, C. 1999. Two new resident birds in northern Zambia. Bulletin of the African Bird Club 6(1): 56-57.

Maclean, I. 2006. What constitutes a species? - a conservation problem. BTO News 264: 10-11.

Maclean, I.; Musina, J.; Nalianya, N.; Mahood, S.; Martin, R.; Byuaruhanga, A. 2003. Systematics, distribution and vocalisations of Payrus Yellow Warbler Chloropeta gracilirostris. Bulletin of the African Bird Club 10(2): 94-100.

Nasirwa, O.; Musina, J.; Nalianya, N. 2000. Response of papyrus-endemic bird species to habitat fragmentation and degradation in Yala Swamp, western Kenya.

Nasirwa, O.; Njoroge, P. 1997. Papyrus-endemic birds in the fringing swamps of Lake Victoria, Western Kenya.

Vande weghe, J. P. 1981. L'avifaune des papyraies du Rwanda et du Burundi. Le Gerfaut 71: 489-536.

Further web sources of information
Explore HBW Alive for further information on this species

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Text account compilers
Ekstrom, J., Evans, M., Pilgrim, J., Shutes, S., Starkey, M., Symes, A., Taylor, J.

Contributors
Baker, N., Bennun, L., Leonard, P., Lindsell, J., Pomeroy, D.

IUCN Red List evaluators
Butchart, S., Taylor, J.

Recommended citation
BirdLife International (2014) Species factsheet: Chloropeta gracilirostris. Downloaded from http://www.birdlife.org on 20/08/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 20/08/2014.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

ARKive species - Papyrus yellow warbler (Chloropeta gracilirostris) 0

Key facts
Current IUCN Red List category Vulnerable
Family Sylviidae (Old World warblers)
Species name author Ogilvie-Grant, 1906
Population size 2500-9999 mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 75,900 km2
Country endemic? No
Links to further information
- Additional Information on this species
- Projected distributions under climate change