Known far and wide as the harbinger of Spring, Common Cuckoos arrive here towards the end of February and leave for Africa again in June. There are two morphs, grey and rufous, grey being very much more common than rufous.
They parasitize various different species, but the most common hereabouts are Reed Warblers. During its breeding period, i.e. any time it's here in Portugal, it is easy to see, sitting out in the open on roadside posts, bare branches and telephone wires. Quite often they sit perched forward with their wings held below their body. Their flight is flat with wing-beats seldom being higher than body level.
Sadly, their numbers appear to be falling. This is a similar story to several other long-distance migrants, such as Barn Swallows and both Woodchat and Iberian Grey Shrikes, but we're still fortunate enough to see all of these, especially Barn Swallows, on a regular basis.
I don't think I have to describe their main call, (if you're having problems with that I suggest you take up another pastime), but their are others that are not so well known, one hoarse, (somewhat resembling the call of a Red-legged Partridge), and one a more melodious burbling trill, likened to that of a Little Grebe, but slower and more melodic.
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