A B

Figure 5.3 Percentages of recoveries of birds ringed in northern European breeding areas that were obtained in three different parts of the eastern Mediterranean region where they were presumed to refuel (see Figure 5.2). A. Northern Libya-Egypt, B. Cyprus, C. Israel-Jordan-Lebanon and Turkey. From Fransson et al. (2005).

could thus be completed in two long stages, separated by a single long stopover for replenishment of reserves. This view is generally supported by other data from Britain, such as their body weights on departure, or their appearance or lack of appearance at coastal bird observatories. Some of the same species have different stopping areas on the return journey, and individuals are seen (and recovered) in much greater numbers in North Africa in spring than in autumn (Chapter 6).

Similar patterns have been described from trans-Saharan migrants breeding further north in Europe (Denmark, Norway, Sweden and Finland), as illustrated in Figures 5.2 and 5.3 (Fransson et al. 2005). From these breeding areas, Thrush

Nightingales Luscinia luscinia, Common Whitethroats Sylvia communis and Red-backed Shrikes Lanius collurio are recovered almost entirely on the Egyptian coast during autumn migration, whereas Barred Warblers S. nisoria and Blackcaps S. atricapilla are recovered mainly in a region embracing Israel, Lebanon, and parts of Jordan, Syria and Turkey. Willow Warblers Phylloscopus trochilus and Lesser Whitethroats S. curruca are recovered in both regions. Trapping activities by local people who supply the recoveries take place throughout all these regions, and the different recovery patterns imply that different species have different major refuelling areas en route to winter quarters. Localised fuelling has long been known in species with restricted habitat areas, such as some waterfowl and shorebirds, but is more surprising in small birds that seem to have lots of suitable habitat distributed along their migration routes. Perhaps again, at this time of year not all this habitat may provide food abundant enough for fuel deposition. However, these staging areas are large, covering thousands of square kilometres, and birds from different parts of the breeding range may use different regions for stopover, as shown, for example, by Lesser Whitethroats from Britain (stopping in northern Italy) and from northern Europe (stopping in the Middle East).

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