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dc.contributor.authorShaw, Philip
dc.contributor.authorSinclair, A. R. E.
dc.contributor.authorMetzger, Kristine
dc.contributor.authorNkwabi, Ally
dc.contributor.authorMduma, Simon A. R.
dc.contributor.authorBaker, Neil
dc.identifier.citationShaw , P , Sinclair , A R E , Metzger , K , Nkwabi , A , Mduma , S A R & Baker , N 2010 , ' Range expansion of the globally Vulnerable Karamoja apalis Apalis karamojae in the Serengeti ecosystem ' , African Journal of Ecology , vol. 48 , no. 3 , pp. 751-758 .
dc.identifier.otherPURE: 161330738
dc.identifier.otherPURE UUID: f1e26c92-2431-4877-b007-57fcf426aaf6
dc.identifier.otherWOS: 000280617600021
dc.identifier.otherScopus: 77955812813
dc.descriptionThis study was funded by the Rufford Maurice Laing Foundation, the Canadian Natural Sciences and Engineering Research Council and Frankfurt Zoological Society.en
dc.description.abstractThe underlying causes of change in geographic range size are less well understood in African birds than in north temperate species. Here, we examine factors associated with range expansion in the Karamoja apalis (Apalis karamojae), a globally Vulnerable warbler confined to north-east Uganda, north-central Tanzania and southern Kenya. In Tanzania, it was originally known only from the Wembere Steppe, but since 1993 (and possibly as early as 1983) has extended its range into the Serengeti ecosystem, c. 140 km to the north, reaching southern Kenya by 2004. Changes in the warbler's range within the Serengeti have broadly reflected a cyclical change in the density of its main habitat, Acacia drepanolobium woodland, which was low in the 1970s, high during the 1980s and 1990s, and declined in the early 2000s. Karamoja apalis records in the Serengeti showed a 5 year time lag behind A. drepanolobium density, which was in turn negatively correlated with the area of grassland burnt 10 years earlier. Previous studies in the Serengeti have also linked Acacia regeneration to changes in grazing pressure, as increasing wildebeest (Connochaetes taurinus) numbers have reduced the volume of combustible material present, and hence the frequency of damaging 'hot burns'. We conclude that this globally threatened warbler appears to have benefited from changes in ungulate populations in the Serengeti, which have influenced burning intensity and hence tree regeneration. The warbler's range now appears to be declining, however, following a recent reduction in the density and annual survival of A. drepanolobium in the northern Serengeti.Resume Les causes sous-jacentes du changement de la taille d'une distribution geographique sont moins bien connues pour les oiseaux africains que pour les especes du nord tempere. Nous examinons ici des facteurs lies a l'expansion de l'aire de repartition de l'apalis de Karamoja Apalis karamojae, un sylviide classe comme Vulnerable au niveau mondial, confine au NE de l'Ouganda, au centre-nord de la Tanzanie et au sud du Kenya. En Tanzanie, on ne le connaissait a l'origine que dans la steppe de Wembere mais depuis 1993, et peut-etre meme des 1983, il a etendu son aire de repartition dans l'ecosysteme du Serengeti, environ 140 km plus au nord, et atteint le sud du Kenya en 2004. Les changements de l'aire de repartition de ce sylviide dans le Serengeti refletent largement un changement cyclique de la densite de son habitat principal, la foret d'Acacia drepanolobium, qui etait faible dans les annees 1970, forte pendant les annees 1980 et 1990, et qui a diminue au debut des annees 2000. Les rapports sur l'apalis de Karamoja au Serengeti montrent un retard de cinq ans par rapport a l'evolution de la densite d'A. drepanolobium, elle-meme etant negativement liee a la zone de prairie brulee 10 ans plus tot. Des etudes anterieures faites au Serengeti lient aussi la regeneration des acacias aux changements de la pression du paturage, etant donne que le nombre croissant de gnous, Connochaetes taurinus, a reduit le volume des matieres combustibles restantes et donc la frequence des feux trop chauds qui causent beaucoup de degats. Nous concluons que cet oiseau menace au niveau mondial semble avoir beneficie des changements des populations d'ongules au Serengeti, qui ont influence l'intensite des feux et donc la regeneration des arbres. L'aire de repartition de ce sylviide semble pourtant en train de se reduire suite a une recente reduction de la densite et de la survie annuelle d'A. drepanolobium dans le nord du Serengeti.
dc.relation.ispartofAfrican Journal of Ecologyen
dc.rights© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd. This is the accepted version of the following article: Range expansion of the globally Vulnerable Karamoja apalis Apalis karamojae in the Serengeti ecosystem Shaw, P., Sinclair, A. R. E., Metzger, K., Nkwabi, A., Mduma, S. A. R. & Baker, N. Sep 2010 In : African Journal of Ecology. 48, 3, p. 751-758, which has been published in final form at
dc.subjectAcacia drepanolobiumen
dc.subjectAcacia seyalen
dc.subjectApalis karamojaeen
dc.subjectGrazing pressureen
dc.subjectHabitat changeen
dc.subjectKaramoja apalisen
dc.subjectRange expansionen
dc.subjectWhistling thornen
dc.subjectWhite thornen
dc.subjectClimate changeen
dc.subjectQH301 Biologyen
dc.titleRange expansion of the globally Vulnerable Karamoja apalis Apalis karamojae in the Serengeti ecosystemen
dc.typeJournal articleen
dc.contributor.institutionUniversity of St Andrews.School of Biologyen
dc.description.statusPeer revieweden

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