Data Zone
Justification of Red List category
This species has a small range, within much of which the extent and quality of its habitat are declining, leading to an increasingly fragmented distribution and probably a declining population. It is therefore considered Vulnerable.
Population justification
Given that the only estimations for any one of this species's subpopulations are for no more than 1,000 individuals, e.g. central Mozambique and the Udzungwa Mts (L. Hansen in litt. 2007), the total population is placed in the range band for 2,500-9,999 mature individuals. This equates to 3,750-14,999 individuals in total, rounded here to 3,500-15,000 individuals.
Trend justification
The population is suspected to be declining, owing primarily to the clearance, degradation and disturbance of habitat across its range. The likely rate of decline has not been calculated.
Swynnertonia swynnertoni is restricted to a few mountains in eastern Zimbabwe, Mozambique and Tanzania. In Zimbabwe, the nominate subspecies occurs at Chirinda and a few other tiny forest patches on the border with Mozambique. In Mozambique, subspecies umbratica is common (D. C. Moyer in litt. 1999, T. Oatley in litt. 1999) on Mt Gorongosa (c.125 km2 of forest in 1970 [T. Oatley in litt. 1999]), and there are possibly no more than 1,000 individuals in central Mozambique (Parker 2005). The species was found 350 km north-east of Gorongosa on Mt Mabu in northern Mozambique in 2008, where there are perhaps 100-200 pairs in 800 ha of forest (Dowsett-Lemaire 2010). In Tanzania, subspecies rodgersi is found 1,100 km to the north in the Udzungwa Mountains, where it is rare to common locally, with densities exceptionally as high as 25 pairs/km2 in secondary forest (Butynski and Ehardt 2003), although it may appear to prefer mature forest (Dinesen et al. 2001). Subspecies rodgersi also occurs another 400 km to the north in lowland patches within the East Usambara Mountains (Anderson et al. 1997), where the subpopulation is probably small (Evans 1997b). The population in the Udzungwa Mountains is thought to number no more than 1,000 birds (L. Hansen in litt. 2007).It appears to be absent from other Eastern Arc mountains, despite apparently suitable habitat being available (N. Burgess in litt. 2012).
All subpopulations are found solely in montane forest (850-1,850 m), apart from in the East Usambaras where it probably occurs only in lowland evergreen forest (130-550 m) (Anderson et al. 1997). On Mt Mabu it occurs from c.1,340 m to the upper limits of the main forest (Dowsett-Lemaire 2010). It favours dense undergrowth with a high density of saplings, or rank growth near streams (Dowsett-Lemaire 2010). In the Bvumba mountains it was found at 1,200-1,850 m in 2007 (C. Chirara in litt. 2012). The species is very intolerant of disturbance and will disappear swiftly from a site if disturbed too often or if vegetation is cut (L. Hansen in litt. 2007). The breeding season for the southern population is October-January (Clancey 1996, Harrison et al. 1997, L. Hansen in litt. 2007). In the Udzungwas, the breeding season is strongly correlated with the rainy season, which begins in early to mid-November and lasts until April, with juveniles seen as late as February (L. Hansen in litt. 2007). The clutch-size is two.
Forest is being cleared on Mt Gorongosa (Harrison et al. 1997, T. Oatley in litt. 1999). The East Usambara subpopulation is threatened by pole-cutting, firewood-collection, cultivation, illegal pit-saw logging and gold mining (Anderson et al. 1997, L. Hansen in litt. 2007). In Bvumba, Zimbabwe, the species is threatened by changes in the forest understorey owing to the spread of the non-native Hedychium, an ornamental ginger (S. L. Childes in litt. 1999), and by clearance for gardens by the new settlers (C. Chirara in litt. 2012). Uncontrolled fires are also a big problem in the Bvumba (C. Chirara in litt. 2012). Forest at higher levels on Mount Mabu is currently under relatively little pressure (Dowsett-Lemaire 2010).
Conservation Actions Underway
In the Udzungwas, the majority of this subpopulation is found within protected areas (D. C. Moyer in litt. 1999). The Ndundulu Mountains lie within the 135,000 ha Kilombero Nature Reserve, which is contiguous with Udzungwa Mountains National Park (N. Burgess in litt. 2012). Conservation projects in the East Usambaras are working to increase the amount of forest, including all lowland remnants, in protected areas (Anderson et al. 1997), and to link the forest patches together through a network of corridors (N. Burgess in litt. 2007); the Derema forest corridor has now been gazetted as a Forest Reserve with work undertaken including financial compensation and provision of alternative farmlands and livelihood supporting projects (Burgess et al. in prep.). In Zimbabwe, Chirinda Forest, Stapleford Forest, Banti Forest and part of Bvumba where the bird occurs are protected areas gazetted by law (C. Chirara in litt. 2012).
Identification: 13-14 cm. Blue-grey upperparts and head. Orange breast. White tiny bib on upper throat (rarely seen in the field), bordered by thin, black line (not always visible). Keeps to the ground. Similar spp. White-starred Robin Pogonocichla stellata is bigger, has yellow breast, darker, longer tail with orange outer tail feathers. However, P. stellata is never seen to come to the ground, always being observed one metre above the ground. Voice Soft, slurred, whistled zitt zitt slurr, last syllable lower-pitched. Alarm note monotonous, quite purring. Hints Usually occurs in pairs (Harrison et al. 1997). Most easily seen at Botanical Gardens, Vumba Mountains (Zimbabwe). It favours a high, closed canopy and open understorey (Anderson et al. 1997, Evans 1997b) where it forages in leaf-litter for invertebrates and small fruit, regularly attending army-ant columns during the dry season (Harrison et al. 1997). It is often abundant where the plant Dracaena fragans is dominant (Harrison et al. 1997).
Text account compilers
Ekstrom, J., Evans, M., Shutes, S., Starkey, M., Symes, A., Taylor, J., Westrip, J.
Contributors
Dowsett, R.J., Moyer, D., Tye, A., Oatley, T., Hansen, L., Chirara, C., Childes, S., Burgess, N., Dowsett-Lemaire, F.
Recommended citation
BirdLife International (2024) Species factsheet: Swynnerton's Robin Swynnertonia swynnertoni. Downloaded from
https://datazone.birdlife.org/species/factsheet/swynnertons-robin-swynnertonia-swynnertoni on 22/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/11/2024.