BirdLife Zimbabwe has a focus on birds, as the name suggests, but birds are just a…
Yellow-bellied Sunbird (a.k.a. Variable Sunbird)
Cinnyrus (Greek = shining) Venustus (Latin = beautiful, charming or graceful); [Family Name = Nectariniidae, eaters of nectar]
(A note on the English name: the standard name for this bird is now “Variable Sunbird”, presumably because the bright yellow belly is just a common variation within the same species. Around here, it is mostly the Yellow-bellied that we see.)
Shona: Dzonya, Tsodzo, Tsodzi, Todzvo, Kadzvororo, Kadzonyn’a (These are what I have found: they appear to be generic names for sunbirds in general within which there are many different types.)
You will almost certainly have seen these bright little birds, flitting and twittering in the branches of flowering shrubs and trees. The picture above brings out the colours very strongly: the iridescent head, neck and shoulders have been caught in a particularly purple light. From another angle, they just look black. But, amazingly, you may not have noticed them. You have to look sharp: they are small (about 10 cm), very busy, and very quick, flicking about among the flowers, sipping nectar and picking off small insects. They can’t afford to waste a second of their time, every one of which has to be spent collecting high octane sugary fuel for their very fast wing-beats. They can hover briefly while they sip nectar from flowers but they cannot (like the hummingbirds in the Americas) actually fly backwards.
The females are a dull brown. Why are the males of many bird species more brightly coloured than the females? Actually, in some species, there is no difference between male and female; and in others, it is the female that is brighter. It’s a matter of the division of labour. If you have as your main purpose in life to attract a mate, a bright plumage helps; in many species, though not all, this would be the male. And if you are the one who has to sit still on the eggs to hatch them even when danger is near – a vulnerable position to be in for yourself and for your eggs – it is probably safer not to be as brightly coloured as a flag; in many but not all species, this is the female. If you both do duty sitting on the eggs, then it is probably better that you both are well-camouflaged. And if you are one of those birds that secretly lay their eggs in the nests of others and so escape altogether the chores of hatching and feeding offspring, you can both wear whatever you like. Whether this tells us anything about how humans dress as they do, and why, I leave you to ponder.
They (I mean the sunbirds, of course!) can be surprisingly noisy, especially the males sitting on the topmost branches of bushes, shouting their hearts out for all to hear. (The recorded call on the site above is not very good at capturing this.) If all this noise is not about attracting a girl-friend, it is about warning other males to stay out of this territory; it may indeed be about both, for territory and mating are the two most important things in a bird’s life. Both are necessary for ensuring that genes are transmitted to the next generation, which is what being a bird is all about.
They used to come regularly to my nectar-feeder – fighting furiously and noisily with each other to dominate the food – and I enjoyed watching them through my bedroom window; but such feeders have to be kept scrupulously clean or else they can become infected with a fungus that does the birds harm. After a while they stopped coming to my feeder and so I concluded I had not done a good enough job in keeping it clean.