Colours of Wildlife: Thickbilled Weaver
Created | Updated Jul 3, 2016
Thickbilled Weaver
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!"
Back to birds, and back to South Africa! This is a species I'm personally well-acquainted with, a Thickbilled Weaver, Amblyospiza albifrons. This is just one of many weaver species of South Africa, but unique in having such a very thick bill. This is the male; the female is dull brown above, white with dark streaks below. It is slightly larger than a sparrow. In spite of its heavy bill, the male can weave very delicately, making one of the most distinctive nests found among all the weavers. This species is not very frequent in South Africa, inhabiting the moister southeastern, eastern and northern parts of the country. It is also found in the moister regions in the rest of sub-Saharan Africa, but is absent from the rainforest belt.
Forests and Reedbeds
With a bill as massive as this, it comes as no surprise that the thickbilled weaver tends to eat hard seeds and fruit stones. It can operate its bill very delicately; it can pick sunflower seeds off the heads, crack open and discard the husks, and swallow the kernels whole. It eats a variety of wild seeds, and is most partial to the stones in the small fruits of White Stinkwood trees, Celtis africana. These trees grow in evergreen forests and also in riverine woodlands, and as part of the woodlands found on rocky hills amidst drier savannah and grassland. The weavers feed in these forests and woodlands, but for nesting use quite a different habitat – reedbeds.
While thickbilled weavers are encountered alone or in pairs while feeding, they breed mostly in small colonies. Dozens of them can nest together in small patches of reeds or sedges. The male is the one who builds the nest. Usually he chooses two upright reed stems that are close together. He first binds these together with long pieces shredded from a reed or sedge leaf. Once he's made a sturdy bridge between the two stems, he stands on this, and weaves the cup that will contain the eggs; then he builds a back wall, and finally a roof. The nest is very densely constructed, and, finished, will even exclude rain. This nest will be used for roosting outside of the breeding season. Once the breeding season arrives, the male will sing at his nest as part of the courtship ritual. After mating, he will change the nest, overlaying a narrow tunnel over the entrance, so the female can just squeeze inside. She will add some lining to the nest to keep it warm, and lay her eggs. Thickbilled weaver eggs look different from the eggs of other weavers: rather than being white or bluish in ground colour, they're pink, with fine, dark reddish spots. The female hatches the eggs alone, and afterwards feeds her chicks on her own also. The chicks are fed with insects, the big and tasty flying termites found in the rainy season being favourites; they are also fed with small aquatic snails. They sometimes fall prey to Gymnogenes, also called Harrier Hawks, which are able to insert their flexible legs into the narrow openings of the nests to get the chicks out.
These fine nests are often abandoned after one or more breeding seasons; after the weavers have left, they're often taken other by other birds, such as orangebreasted waxbills (which also occur in reedbeds) or even by mice!
Expanding Range
This is one species which seems to be doing well living alongside humans. In fact, it has even managed to expand its range in recent years. When I was young, this weaver was restricted to moist, low-lying eastern regions of the country. It wasn't seen far inland. The first one I saw was in the Pretoria Botanical Gardens, which is far inland from its main range. Later I saw them at the Polokwane Bird Sanctuary, where there are extensive reedbeds – I saw their distinctive nests there too – I saw one in the city of Pretoria when I was taking my mom there to visit my dad in hospital; and now, they are even coming into my own garden here in Polokwane! It may be that they are taking advantage of human gardens, which are quite similar to the lush woodlands and forests where they feed. People even plant the stinkwood trees, which provide their favourite fruits, in their gardens! In addition, people have created many new lakes and ponds fringed with reeds and rushes, giving them a lot more places where they can nest and breed. They also make use of the leaves of palm trees, which many people plant in their gardens, for nesting material. This is therefore one species that's at the moment not in any danger of extinction. This is good because it is quite a unique and special member of the weaver family.
