At that time of the year when spring is moving towards summer, a new bird call, familiar from last year, is heard with growing frequency throughout most of southern Africa, excluding the really arid regions. A loud and persistent deed-deed-deed-deed-er-ick. This is the striking and distinctive call that gives the Diderick cuckoo its onomatopoetic name, which you may sometimes find written as “Diederik” or “Dideric”. It is the male who does the calling, energetically declaring his territory and no doubt letting the females know where he can be found.
Like most cuckoos, the Diderick cuckoo is heard more often than it is seen, although it is not quite as retiring as some of its relatives. It is a one of the smaller cuckoos, with a length of about 20 cm; green above and with whitish underparts. They have a broken white eyestripe, a green moustauchial stripe, and green outer tail feathers adorned with white spots. Eyes are red; the bill black and legs and feet grey. Females differ slightly in plumage and are slightly larger than males.
It is generally a solitary bird and is found singly in open woodland and savanna, eschewing forests and plantations. In keeping with other cuckoos, the Diderick cuckoo is a brood parasite, although it is perhaps less discriminatory in its choice of host than some, and has been known to parasitise at least 24 other species. The most common amongst these are the sparrows, weavers (including the bishops) and the wagtails, all of which are significantly smaller than the Diderick cuckoo, and are thus faced with an extremely challenging task when it come to feeding the hatchling.
Diderick cuckoos are intra-African migrants and arrive in southern Africa from central or east Africa in September/October and depart again in March/April. They feed mainly on caterpillars and insects.
Being a brood parasite is not a totally idyllic life, and while the males are letting the world know who and where they are with their characteristic call, the females must locate a suitable nest which is at the right stage in the breeding cycle, locate a male to mate with (this is the easy part!) and then enter the well guarded host’s nest undetected to lay her egg amongst the host’s clutch and then leave again. Not an easy task in view of the heightened alertness of all birds during the breeding period.
The scientific binomial of the Diderick cuckoo is Chrysococcyx caprius; Chrysococcyx from the Greek for a golden cuckoo, in reference to the metallic sheen of the plumage and caprius from the Latin for like a goat – a careless error as the spelling should have been cupreus from the Latin for like copper. By the time the error was realized, cupreous had been given to the African emerald cuckoo (Chrysococcyx cupreus) and so the inappropriate goat-reference was left . Thus we have a metallic cuckoo that looks like a goat. Oops! A metallic cuckoo that has a coppery sheen – that’s better.