Discussion 
The most striking data are the low numbers of Buzzards seen in 1990 com- 
pared with 1978 and 1980. Furthermore, Andrews et al. (Andrews et ah, 1977) 
observed 205,000 Buzzards between 17 August and 10 October 1977. A reason- 
able explanation for this might be that migrating birds follow different routes 
in the area, according to prevailing weather conditions. During bad weather 
conditions and when the Coruh Valley is filled with clouds, the birds are sup- 
posed to follow the coastline (Andrews et al., 1977); in bright weather they fol- 
low roughly the Coruh River. 
In very good weather conditions we observed hardly any passage on 19 
September in the Arhavi area. On 21 September there was similarly little pas- 
sage so we left at 1100 h.. At c. 1300 h. we arrived at Bor^ka where many rap- 
tors were migrating and this went on until the end of the afternoon. We sup- 
pose that on these two or three days (19, 20 and 21 September) with good 
weather a substantial proportion of Buzzards passed by Borgka, following the 
Coruh route. Note that we had bad weather on 20 September at Arhavi, but 
this does not necessarily suggest there was bad weather further inland (at 
Bor^ka). Counting at Hopa might solve the problem of choosing an observa- 
tion point. 
For the other species some differences in numbers can be seen, but it is hard to 
compare these data since there are more than ten years between different cen- 
suses. It is also clear that to obtain reliable data simultaneous observations at 
Bor^ka and Arhavi are needed. This would also provide an opportunity to 
find out whether some species prefer the coastal route (e.g. Black Kite?) or the 
Coruh route (e.g. eagle spp.?) irrespective of the weather. 
References 
ANDREWS, J. et al. (1977) A 'new' raptor migration route through the North 
of East Turkey. Bull. Orn. Soc. Turkey 14: 2-5. 
BIJLSMA, R.G. (1987) Bottleneck areas for migratory birds in the Mediteranean 
region. ICBP study-report 18. International Council for Bird Protection. 
Cambridge. 
KASPAREK, A. and KASPAREK, M. (1990) Reisefuhrer Natur Turkei. 
Springer. Munich. 
Marcel Kok, Van Essenstraat 93, 7203 DK, Zutphen, The Netherlands. 
Jean Paul OngenaeMozartlaan 541, 5011 SM, Tilburg, The Netherlands. 
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