After a bit of a cloudy start, today turned into a lovely, warm autumn day. At 1800hrs there was a group of 15 Common Raven over the south of the village. A visit to the west slope of El Hacho from 1830-1930hrs produced Griffon Vulture, Short-toed Eagle ('local'?), Common Kestrel, 3 Common Raven, Blue Rock Thrush, Crag Martin, Stonechat, Sardinian Warbler, a flock of 20+ Goldfinch, and Cirl Bunting.
Once again, the Southern Grey Shrike was absent; it was last seen on 31 July. It occurred to me that maybe it was out-competed by the Common Kestrels that have been in the area since late summer. Although the two species target similar prey, it would seem that they don't compete due to prey size differences, as discussed in the following paper,
Padilla D. P., Nogales M., Marrero P. 2007. Prey size selection of
insular lizards by two sympatric predatory bird species. Acta Ornithol.
42: 167–172.
So maybe the shrike was just disturbed by the presence of the kestrels?
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