Colours of Wildlife: Yellowfronted Tinkerbird
Created | Updated Apr 22, 2018
Yellowfronted Tinkerbird
Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours. . . but actually many media including 'digital' paintings with the computer!"
What you have here is one of South Africa's smallest and most charming avians, a Yellowfronted Tinkerbird, also called a Yellowfronted Tinker Barbet, Pogoniulus chrysoconus. It is indeed a member of the African Barbet family, the Lybiidae, which is related also to woodpeckers, toucans, Asian and tropical American barbets, and honeyguides. Tinkerbirds constitute a group of tiny barbets, ranging from 10-13 cm/4"-5" in total length. They get their common name from the golden-yellow, crown-like patch of feathers on their foreheads, and from their repetitive, ringing 'tink-tink-tink-tink' calls. This sounds somewhat like a small hammer clinking on an anvil. Slight differences in the tempo and timbre of these calls distinguish the different tinkerbird species. Their calls are very characteristic, and heard over most of the wooded regions of Africa. Calling tinkerbirds turn their heads from side to side as they 'tink', giving their calls a ventriloquial quality so as to not give their exact position away.
Tiny Excavators
The barbet family, being closely related to woodpeckers, are also known for excavating wood. But they don't use the hammering style of the woodpeckers, instead using their stout bills to bite onto a wad of wood and then wrench it free, repeating the process until they've made a fair-sized cavity. And they do this not for finding food, but for excavating nesting and roosting holes. For tinkerbirds, this cavity doesn't need to be very big to suit their needs. It is excavated in soft-wooded or dead trees, sometimes even in the stumps people have gathered for firewood and left in a pile to dry out. They often dig the hole in the underside of a branch. The entrance hole is about 2 cm/slightly less than an inch in diameter, and leads to a small nesting chamber. Because of the small size of the opening, these nests are quite difficult to spot. They're also so small that the tinkerbirds are fairly safe from being parasitized by the larger honeyguides during the breeding season. Lastly, the small size of the tinkerbirds and their cavities means that they can be more easily accommodated. In the savannahs and dry woodlands of South Africa, there is vehement competition for nest holes among the various different hole-nesting birds. And even mammals like squirrels get into the act, often evicting birds from their own nests. A scarcity of very large trees makes it especially hard for large hole-nesters such as hornbills to find suitable sites. But the tiny tinkerbirds can fit their little cavities into medium-sized or small trees, of which there are an abundance.
In South Africa, tinkerbirds breed in the summer. The two or three eggs the female lays hatch into naked, helpless chicks. They're brooded and fed by both parents, and fledge (probably) by the age of three weeks or so. The parents also remove their excrement, which is either contained in a small sac or in a wad of wood chips, which the adult birds drop well away from the nest site. Towards the end of their nestling phase, the chicks climb up to the nest opening, taking turns to peer out as they await the food brought by their parents. After fledging, they go out seeking food with their parents, and the whole family returns to the nest to roost at night. Once fully adult, the offspring will strike out to find their own mates and territories.
Tinker barbets eat small amounts of fruit, such as the sweet berries of mistletoe plants. Mistletoe-like plants are diverse and abundant in South Africa, many having quite pretty and unusual flowers. They're parasitic plants, growing mostly on trees, with a root system that penetrates the vessels of the branch they're growing on, stealing water and nutrients from their hosts. Mistletoes make sweet berries to attract fruit-eating birds. The fruit pulp, while containing much sugar and nutrition, is also extremely sticky. When eating a mistletoe berry, the tinkerbird usually doesn't eat the rather large seed, but wipes it off its bill onto a twig or branch. And there the mistletoe seed sticks! It quickly germinates and sends its roots right into the twig or branch and so a new little plant parasite gets started. Tinkerbirds are therefore important seed dispersal agents for the many mistletoe species.
But tinkerbirds mainly hunt insects. They do this often as part of the mixed-species bird parties frequently encountered in savannah and woodland regions. In such a party, each bird species uses a different hunting method and targets a different section of the invertebrate fauna; this means efficient hunting since what one bird misses gets picked up by another. Tinkerbirds use a gleaning strategy, hopping about the treetops, methodically inspecting the upper and lower sides of twigs and leaves and rapidly pecking up any little critter they find.
Due to their size, and the difficulty in finding the precise location of a calling bird, tinkerbirds are hard to spot, even in regions where they are common. But in suitable habitat, with a good pair of binoculars, and some patience, you stand a good chance of glimpsing and observing one or two of these charming little birds. Yellowfronted tinkerbirds occur widely not only in the northern parts of South Africa, but also in the rest of sub-Saharan Africa, only being absent from dry deserts and treeless grasslands, the rainforest belt, and much of Eastern and north-Eastern Africa where they're replaced by the Redfronted Tinkerbird. Funnily enough in South Africa a race of the yellowfronted species occurs which has an orange or red forehead patch, making it almost indistinguishable from the redfronted species. But it can be separated on distribution and habitat, the redfronted not occurring in the same region and (in South Africa at least) inhabiting moister and more densely forested habitat. At present, the yellowfronted tinkerbird is by no means threatened.
