Notes on the behaviour, plumage and distribution of the White-tailed Swallow Hirundo megaensis

The White-tailed Swallow Hirundo megaensis is a threatened and poorly known bird endemic to southern Ethiopia, where it is restricted to a small area of Acacia savanna. Despite the paucity of previous nest records, we found 67 nests in the years 2010–14, commonly in village huts lived in by people, and report the first confirmation of nesting (two certain records) in termite mounds. Its nests are small mud cups lined with grass and animal hair, fixed to roof joists and similar to those of its sister species, the Pearl-breasted Swallow H. dimidiata of southern Africa, although it appears to lay larger clutches (3–4 pure white eggs) and breed less frequently, producing one brood in each of its two rain-driven breeding seasons (April–June and October–November). The same nests are reportedly used in these two seasons, presumably by the same pairs. Incubation lasts 16–17 days, with some broods showing clearly smaller chicks and hence presumably asynchronous hatching. Study of nestlings in the hand and museum skins confirmed that juveniles can be determined by their shorter tails, browner heads and frequently also wings, and reduced white in the tail. Although birds are typically seen singly or in pairs, flocks of up to 50, sometimes mixed with other hirundines, can occur. The breeding range appears to be almost identical to that of the Ethiopian Bush-crow Zavattariornis stresemanni but regular sightings of White-tailed Swallows since 2005 at the Liben Plain, 120 km to the east of the core area, suggest that the birds are frequent visitors there.We are grateful to the numerous funding bodies which have supported this research over several years: NERC, RSPB, British Birdfair, African Bird Club, British Ornithologists’ Union, Gesellschaft für Tropenornithologie, Tim Whitmore Zoology Fund, Magdalene College (Cambridge), Cambridge Philosophical Society, and BirdLife Preventing Extinctions Programme; and especially to Julian Francis. We also thank Robert Prys-Jones at the Natural History Museum (NHMUK) for access to specimens; Les Colley for his photograph used in Fig. 5; Stefanie Rick for her excellent drawings used in Fig. 9; Steve Rooke (Sunbird Tours), Bernard, Willem and Sjoerd Oosterbaan, Simon Busuttil, Merid Gabremichael and Claire Spottiswoode for providing additional information and sightings; Alazar Dakar, Abiy Dange, Birhan Dessalegn, Solomon Desta, Okotu Dida, Ali Guche, Sam Jones, Gufu Kashina, Stuart Marsden, Tesfaye Mekonnen, Samson Zelleke and many others including all the staff of Borana National Park for help with fieldwork; Angela Turner and John Atkins for their services as referees; and the Borana villagers who so kindly allowed us into their homes to study the White-tailed Swallow’s nests and without whose hospitality our knowledge of this species would be much poorer.This is the author accepted manuscript. The final version is available from African Bird Club

Varied diet and opportunistic foraging in the Ethiopian Bush-crow Zavattariornis stresemanni, an Endangered generalist

The Ethiopian Bush-crow Zavattariornis stresemanni is an endangered, co-operatively breeding southern Ethiopian endemic with a remarkably restricted range (c. 6 000 km2). The species’ range was recently found to be almost perfectly predicted by an envelope of cooler, drier and more seasonal climate than surrounding areas, but the proximate determinants of this range restriction remain unclear. We assessed whether specialisation in diet or foraging may restrict the range of the species by conducting foraging watches to determine prey composition, augmented by observations of opportunistic foraging techniques, and by comparing our results to previously published information on diet. Prey composition comprised a range of arthropods, such as insect larvae (62.7%), beetles (Coleoptera) (15.6%), and grasshoppers and crickets (Orthoptera) (11.8%). Prey was primarily obtained by pecks above ground (74.2%) but also frequently dug up (23.8%). Prey capture was most successful during pecks and we also found chicks were preferentially fed larger prey items over smaller ones by adults. We documented opportunistic behaviours such as nest-raiding and ox-pecking. Diet and foraging are varied and unspecialised, and therefore do not appear to explain the restricted range of the Ethiopian Bush-crow

Climatic change and extinction risk of two globally threatened Ethiopian endemic bird species.

Climate change is having profound effects on the distributions of species globally. Trait-based assessments predict that specialist and range-restricted species are among those most likely to be at risk of extinction from such changes. Understanding individual species' responses to climate change is therefore critical for informing conservation planning. We use an established Species Distribution Modelling (SDM) protocol to describe the curious range-restriction of the globally threatened White-tailed Swallow (Hirundo megaensis) to a small area in southern Ethiopia. We find that, across a range of modelling approaches, the distribution of this species is well described by two climatic variables, maximum temperature and dry season precipitation. These same two variables have been previously found to limit the distribution of the unrelated but closely sympatric Ethiopian Bush-crow (Zavattariornis stresemanni). We project the future climatic suitability for both species under a range of climate scenarios and modelling approaches. Both species are at severe risk of extinction within the next half century, as the climate in 68-84% (for the swallow) and 90-100% (for the bush-crow) of their current ranges is predicted to become unsuitable. Intensive conservation measures, such as assisted migration and captive-breeding, may be the only options available to safeguard these two species. Their projected disappearance in the wild offers an opportunity to test the reliability of SDMs for predicting the fate of wild species. Monitoring future changes in the distribution and abundance of the bush-crow is particularly tractable because its nests are conspicuous and visible over large distances

Climatic change and extinction risk of two globally threatened Ethiopian endemic bird species.

Climate change is having profound effects on the distributions of species globally. Trait-based assessments predict that specialist and range-restricted species are among those most likely to be at risk of extinction from such changes. Understanding individual species' responses to climate change is therefore critical for informing conservation planning. We use an established Species Distribution Modelling (SDM) protocol to describe the curious range-restriction of the globally threatened White-tailed Swallow (Hirundo megaensis) to a small area in southern Ethiopia. We find that, across a range of modelling approaches, the distribution of this species is well described by two climatic variables, maximum temperature and dry season precipitation. These same two variables have been previously found to limit the distribution of the unrelated but closely sympatric Ethiopian Bush-crow (Zavattariornis stresemanni). We project the future climatic suitability for both species under a range of climate scenarios and modelling approaches. Both species are at severe risk of extinction within the next half century, as the climate in 68-84% (for the swallow) and 90-100% (for the bush-crow) of their current ranges is predicted to become unsuitable. Intensive conservation measures, such as assisted migration and captive-breeding, may be the only options available to safeguard these two species. Their projected disappearance in the wild offers an opportunity to test the reliability of SDMs for predicting the fate of wild species. Monitoring future changes in the distribution and abundance of the bush-crow is particularly tractable because its nests are conspicuous and visible over large distances

Climatic change and extinction risk of two globally threatened Ethiopian endemic bird species

Funder: Royal Society for the Protection of BirdsFunder: British Birdfair/RSPB Fund for Endangered SpeciesFunder: African Bird Club; funder-id: http://dx.doi.org/10.13039/100014663Funder: British Ornithologists’ Union; funder-id: http://dx.doi.org/10.13039/100008023Funder: Cambridge Philosophical Society; funder-id: http://dx.doi.org/10.13039/100013858Funder: Tim Whitmore FundFunder: Worts Travelling Scholars FundFunder: Magdalene College, University of Cambridge; funder-id: http://dx.doi.org/10.13039/501100000653Climate change is having profound effects on the distributions of species globally. Trait-based assessments predict that specialist and range-restricted species are among those most likely to be at risk of extinction from such changes. Understanding individual species’ responses to climate change is therefore critical for informing conservation planning. We use an established Species Distribution Modelling (SDM) protocol to describe the curious range-restriction of the globally threatened White-tailed Swallow (Hirundo megaensis) to a small area in southern Ethiopia. We find that, across a range of modelling approaches, the distribution of this species is well described by two climatic variables, maximum temperature and dry season precipitation. These same two variables have been previously found to limit the distribution of the unrelated but closely sympatric Ethiopian Bush-crow (Zavattariornis stresemanni). We project the future climatic suitability for both species under a range of climate scenarios and modelling approaches. Both species are at severe risk of extinction within the next half century, as the climate in 68–84% (for the swallow) and 90–100% (for the bush-crow) of their current ranges is predicted to become unsuitable. Intensive conservation measures, such as assisted migration and captive-breeding, may be the only options available to safeguard these two species. Their projected disappearance in the wild offers an opportunity to test the reliability of SDMs for predicting the fate of wild species. Monitoring future changes in the distribution and abundance of the bush-crow is particularly tractable because its nests are conspicuous and visible over large distances

Climatic change and extinction risk of two globally threatened Ethiopian endemic bird species.

Climate change is having profound effects on the distributions of species globally. Trait-based assessments predict that specialist and range-restricted species are among those most likely to be at risk of extinction from such changes. Understanding individual species' responses to climate change is therefore critical for informing conservation planning. We use an established Species Distribution Modelling (SDM) protocol to describe the curious range-restriction of the globally threatened White-tailed Swallow (Hirundo megaensis) to a small area in southern Ethiopia. We find that, across a range of modelling approaches, the distribution of this species is well described by two climatic variables, maximum temperature and dry season precipitation. These same two variables have been previously found to limit the distribution of the unrelated but closely sympatric Ethiopian Bush-crow (Zavattariornis stresemanni). We project the future climatic suitability for both species under a range of climate scenarios and modelling approaches. Both species are at severe risk of extinction within the next half century, as the climate in 68-84% (for the swallow) and 90-100% (for the bush-crow) of their current ranges is predicted to become unsuitable. Intensive conservation measures, such as assisted migration and captive-breeding, may be the only options available to safeguard these two species. Their projected disappearance in the wild offers an opportunity to test the reliability of SDMs for predicting the fate of wild species. Monitoring future changes in the distribution and abundance of the bush-crow is particularly tractable because its nests are conspicuous and visible over large distances