Grauer’s scrub-warbler  (Bradypterus graueri)

Classified as Endangered (EN) on the IUCN Red List 2007 (1).

While visually unexciting, the Grauer’s scrub-warbler is interesting for only inhabiting swamps in the mountains of central Africa (2). Its plumage is dark brown, with bold streaks on the throat and a slight russet tinge to its long, graduated tail (2) (3). The Grauer’s scrub-warbler’s underparts are whitish and a fairly distinct white line runs, like an eyebrow, just above the eye. The bill is black and the legs are pale brown to flesh-coloured (2).

The Grauer’s scrub-warbler has a fragmented distribution in central Africa; in Democratic Republic of Congo, Uganda, Rwanda and Burundi (2).

Inhabits mountain swamps at altitudes of 1,950 to 2,600 metres, where it can be found in a range of swamp vegetation, including grasses, mosses, rushes and ferns (2).

Small seeds and insects, such as beetles and caterpillars, make up the majority of the Grauer’s scrub warbler’s diet, which it searches for near the ground (2). They are monogamous and territorial birds, with each pair defending an area of 0.1 to 0.5 hectares during the breeding season (4). The breeding season is thought to occur in February and March in Democratic Republic of Congo (2); outside of this period, Grauer’s scrub-warblers have been observed moving around their swamp habitat in groups of 10 to 12 birds (4).

The montane swamps which the Grauer’s scrub-warbler inhabits are not well protected, and therefore habitat destruction and alteration poses the greatest threat to this species. The largest population occurs in Rugezi swamp, Rwanda (3); an area which is being degraded and encroached by agriculture (2). Many smaller swamp sites, particularly those near dense human settlements, are also being drained for cultivation or pasture (2) (3).

Several of the swamps which Grauer’s scrub-warblers inhabit are protected within national parks, such Bwindi-Impenetrable Forest National Park, Uganda and Kahuzi-Biéga National Park, Democratic Republic of Congo (2), (both World Heritage Sites) (5). However, the latter is not secure (3), having been badly affected by influxes of Rwandan refugees and rebel soldiers (6). Rugezi swamp in Rwanda, home to the largest population of Grauer’s scrub-warblers, urgently needs protection (3). An action plan which outlines a strategy to improve the conservation status of the Grauer’s scrub warbler was published in 2006. Priority actions include determining the distribution, population size and trends of the species and minimising the impact of human activities at key sites (4). Hopefully these measures will lessen the Grauer’s scrub-warbler’s risk of extinction.

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on Grauer’s scrub-warbler see:

• Byaruhanga, A., Sande, E., Plumptre, A., Owiunji, I. and Kahindo, C. (2006) International Species Action Plan for the Grauer’s Swamp-warbler Bradypterus graueri. BirdLife International, Nairobi, Kenya and Royal Society for the Protection of Birds, Sandy, Bedfordshire, UK.