From the 20th to the 25th of April, Lycabettus Hill was "flooded" by Ficedula spp. flycatchers. Birds were everywhere, calling and defending their space from each other. In a patch less than 100 meters long once could see all three species!
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Collared Flycatchers were the first to arrive and in the early days they outnumbered
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As days passed,
Pied Flycatchers built up their numbers and dominated the forest.
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Semi-collared Flycatchers were also seen, in much smaller numbers of course.