TY - JOUR

T1 - Known and predicted African winter distributions and habitat use of the endangered Basra reed warbler (Acrocephalus griseldis) and the near-threatened cinereous bunting (Emberiza cineracea)

AU - Walther, Bruno A.

AU - Wisz, Mary S.

AU - Rahbek, Carsten

N1 - Funding Information: Acknowledgements We thank the many people and institutions who have helped our project called ‘‘A database of Western Palearctic birds migrating within Africa to guide conservation decisions’’ and who are acknowledged on the website http://www.zmuc.dk/Ver- Web/STAFF/Bawalther/migratoryBirds-africa.htm. For providing references for this particular study, we specifically thank Linda Birch, Robert Dowsett, Louis Hansen, Sue Robinson, and the librarians at BirdLife International, Cambridge, and the Royal Society for the Protection of Birds, Sandy, especially Ian Dawson and Lynn Giddings. Our thanks also go to Elizabeth and Neil Baker, Robert Dowsett, John Miskell, Gerhard Nikolaus, David Pearson, and Robert Pryˆ s-Jones, who have shown a special interest in our study and provided very useful data, to Robert Hijmans who greatly helped with GIS applications, and to Andrzej Dyrcz and one anonymous referee for insightful comments. B.A.W. was financed through a two-year Marie Curie Individual Fellowship funded by the European Commission’s ‘‘Improving Human Research Potential’’ programme, administered by the European Commission Research Directorate General in Brussels. C.R. acknowledges the Danish National Science Foundation grant no. I. hr. 21–03–0221 for support.

PY - 2004

Y1 - 2004

N2 - The Basra reed warbler (Acrocephalus griseldis) and the cinereous bunting (Emberiza cineracea) are the only two Western Palearctic passerine bird species that overwinter in East Africa and are classified by BirdLife International as endangered and near-threatened, respectively. To refine the African wintering ranges of these two species, we made an effort to collect as much distributional data as possible. We then used the available point-locality data to predict the wintering distributions using a Geographic Information Systems (GIS) based inductive modelling technique called BIOCLIM. For this purpose, we developed four environmental GIS layers that are presumed to reflect the environmental preferences of migrant birds. Our data showed that the known winter distribution of the Basra reed warbler was concentrated in Kenya, Tanzania, Malawi and Mozambique, where it was usually found in dense vegetation growing in coastal scrub, woodland thickets, swamps, marshes, flooded pools and grasslands, and along ditches and edges of rivers, ponds, lagoons and lakes. The predicted winter distribution of this species includes most of East Africa but, given the habitat preferences of this species, is probably limited to low-lying areas near the coastline. The known winter distribution of the cinereous bunting is so far limited to Eritrea, where the species has been observed in October, November, February and March, in sparsely vegetated, sandy or rocky habitats on coastal plains and deserts. The predicted winter distribution of this species includes the plains and hills along the Red Sea coasts in southern Egypt, Sudan, Eritrea, Ethiopia and Sudan, as well as a few inland areas in Sudan, Ethiopia and Kenya.

AB - The Basra reed warbler (Acrocephalus griseldis) and the cinereous bunting (Emberiza cineracea) are the only two Western Palearctic passerine bird species that overwinter in East Africa and are classified by BirdLife International as endangered and near-threatened, respectively. To refine the African wintering ranges of these two species, we made an effort to collect as much distributional data as possible. We then used the available point-locality data to predict the wintering distributions using a Geographic Information Systems (GIS) based inductive modelling technique called BIOCLIM. For this purpose, we developed four environmental GIS layers that are presumed to reflect the environmental preferences of migrant birds. Our data showed that the known winter distribution of the Basra reed warbler was concentrated in Kenya, Tanzania, Malawi and Mozambique, where it was usually found in dense vegetation growing in coastal scrub, woodland thickets, swamps, marshes, flooded pools and grasslands, and along ditches and edges of rivers, ponds, lagoons and lakes. The predicted winter distribution of this species includes most of East Africa but, given the habitat preferences of this species, is probably limited to low-lying areas near the coastline. The known winter distribution of the cinereous bunting is so far limited to Eritrea, where the species has been observed in October, November, February and March, in sparsely vegetated, sandy or rocky habitats on coastal plains and deserts. The predicted winter distribution of this species includes the plains and hills along the Red Sea coasts in southern Egypt, Sudan, Eritrea, Ethiopia and Sudan, as well as a few inland areas in Sudan, Ethiopia and Kenya.

KW - Acrocephalus griseldis

KW - BIOCLIM

KW - Emberiza cineracea

KW - Migration

KW - Wintering distribution

U2 - 10.1007/s10336-004-0036-7

DO - 10.1007/s10336-004-0036-7

M3 - Journal article

AN - SCOPUS:7744240204

VL - 145

SP - 287

EP - 299

JO - Journal fur Ornithologie

JF - Journal fur Ornithologie

SN - 0021-8375

IS - 4

ER -