This species has a very small and severely fragmented range. Away from its strongholds in Arabuko-Sokoke and the East Usambaras, it is found only very locally, even within suitable evergreen forest habitat. Forest clearance and alteration are ongoing over much of its range, and its population and range are therefore presumed to be declining. For these reasons, it is listed as Endangered.
9 cm. Small woodland sunbird. At close range, upperparts and head of male are iridescent, deep green. Belly, flanks and vent contrasting white. When agitated, shows red pectoral tufts. Female overall greyish. Similar spp. Female Plain-backed Sunbird A. reichenowi has olive and yellow tones. Voice Song high-pitched jumble of chissick's and other unmusical notes. Contact call seeet seeet. Hints Most reliably and frequently seen at Arabuko-Sokoke Forest, Kenya, and around Amani in the East Usambaras, Tanzania.
The species is known to occur in three areas. Its population in the Brachystegia woodland of Arabuko-Sokoke Forest, Kenya, has been estimated at 2,818 individuals (95% CI: 1,739-4,565) in an area of 77 km2. The remaining occupied range in the East Usambara and Udzungwa Mountains, Tanzania, totals 420 km2, with the population in the Udzungwa Mountains probably numbering 'some hundred' individuals. Its population is therefore suspected to fall within the band 2,500-9,999 individuals. This equates to 1,667-6,666 mature individuals, rounded here to 1,500-7,000 mature individuals.
The comparison of transect survey data from the 1970s and 1999 suggests that the species has declined in Arabuko-Sokoke Forest, Kenya, over this period, despite differences in the survey methods. This decline is suspected to be continuing, owing to the ongoing degradation of woodland in this area. The species is suspected to be declining in Tanzania, in line with the loss and degradation of forest. The likely overall rate of decline has not been estimated.
It occurs in pairs or family groups, often joining mixed-species flocks in the canopy of mature trees in intact Brachystegia forest, often 30-35 m above ground, and in sub-montane evergreen forests in the East Usambara and Udzungwa Mountains. However, it has also been recorded outside intact, unlogged forest, visiting flowers only a few metres above ground in clearings, gardens and very degraded forest.
During 2006 surveys in the East Usambaras it was found in cultivated areas, including nesting in a Eucalyptus plantation, but was not found further than 800 m from forest. The diet includes nectar (e.g. mistletoes Loranthus and Erythrina), insects and other arthropods . Aggressive interactions with Collared Sunbird A. Collaris suggest that competition with this species may contribute to its restricted distribution.
At Arabuko-Sokoke, widespread felling of trees (often illegally) for poles, carving and fuelwood is altering the forest structure and probably having a negative impact on the species, since it shows a significant preference for primary forest here. Throughout the East Usambaras, the main threats to forest extent and integrity are clearance for cultivation, excessive pole-cutting, and pit-sawing outside reserves. All are likely to increase in the near future.
In the Udzungwa Mountains, the forests are considered less threatened, although there have been several illegal logging attempts locally (L. Dinesen in litt. 2007). The species, however, may be able to tolerate some forest degradation (Evans 1997b, Seddon et al. 1999b).
