Distribution, abundance and habitat preferences of White-tailed Swallow Hirundo megaensis and Ethiopian Bush-crow Zavattariornis stresemanni, two southern Ethiopian endemics

• Published in: Bird conservation international 2008-12, Vol.18 (4), p.395-412
• Main Authors: MELLANBY, R. J., ROSS, B., WATT, A., WONDAFRASH, M., EWNETU, M., BROADHURST, C., CRITCHLOW, R., DADESA, A., DEAS, T., ENAWGAW, C., GEBREMEDHIN, B., GRAHAM, E., MacLEAN, S., McKEAN, M., COLLAR, N. J., SPOTTISWOODE, C. N.
• Format: Article
• Language: English
• Subjects: Acacia; Agricultural expansion; Agricultural land; Conservation status; Encroachment; Endangered species; Endemic species; Habitat preferences; Habitats; Hirundo; Threatened species; Woodlands
• ISSN: 0959-2709; 1474-0001
• DOI: 10.1017/S0959270908007314

The Yabelo–Mega region of southern Ethiopia's Borana region holds two threatened endemic and restricted-range species, the White-tailed Swallow Hirundo megaensis (‘Vulnerable’) and Ethiopian Bush-crow Zavattariornis stresemanni (‘Endangered’). Concern about these species’ conservation status has recently increased owing to rapid alterations to their thornbush savanna habitat. This six-week field study aimed to identify the specific habitat requirements of each species, with a view to understanding how they are likely to be affected by these changes, and to provide baseline quantitative abundance data using simple and repeatable methods. White-tailed Swallows were recorded on an overall 4.7% of transects and point counts, and in all habitats (including villages and farmland) except broadleaved Combretum–Terminalia woodland. Line transects indicated that swallows avoided dense scrub and tree cover, but this was not detected during point counts. Bush-crows were recorded on an overall 16.6% of transects and point counts, and like swallows showed a strong preference for thornbush (Acacia and Commiphora) over broadleaved woodland, avoided dense scrub cover, and were particularly frequent in the vicinity of villages. During point-counts, bush-crows were more frequently encountered inside the nominally protected Yabelo Sanctuary, whereas the reverse was true for White-tailed Swallows. Recent concern about dramatic declines in bush-crow numbers revealed by roadside counts may have been exacerbated by habitat alteration along roads alone, but the species remains under threat from habitat transformation through agricultural expansion, tree felling and bush encroachment.