Colours of Wildlife: Long-Tailed Widowbird
Created | Updated Jun 1, 2014
Long-tailed Widowbird
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!"
This week I bring you a bird that has made a great impression on me! This is a Long-tailed Widowbird, Euplectes progne. Here in South Africa we also call it a Sakabula, which is derived from its Zulu name. It is a relative of weavers such as the Sociable Weaver. It has a very interesting range of distribution, being found over the eastern half of South Africa, then, after a huge gap, in numerous patches of grassy regions in central Africa, and after another huge gap, in the grassy highlands of Kenya. It is the largest species in the genus Euplectes, the Bishops and Widowbirds. They are all seed-eating birds, of around sparrow size in the body, although they can look much bigger with their extravagant breeding feathers.
The Male Widow
The funny thing about the name of the widowbirds is that the widows are male! The name comes from the black plumage and only the males get it, and that, too, only during the breeding season. In my drawing, you can see what the male and female look like outside of the breeding season: the male loses all of the black feathers, only retaining the orange-red shoulder patch. He looks much like the drab, streaky female, only being slightly larger.
All of the widowbird males change into mainly black plumage in the breeding season. But they differ much between them. Many develop long black tails, others retain short or only slightly lengthened tails. Most of them have yellow, orange or red patches on their heads, throats, wings or backs. In the same genus there are also species called bishops. These are a bit smaller, and never grow long tails, instead getting more extensive areas of bright red, orange or yellow feathers on their bodies. They display by fluffing out these bright feathers, while the widows generally display more by drawing attention their long tails.
Sooty Feathers in the Wind
My memories of this bird go back to when I was a small child. I was born in Pretoria and lived there for my first eight years of life. Many of my relatives lived in and around Benoni, and my mother's family lived in the Free State. These regions are in the Highveld, the central plateau region of South Africa, the natural vegetation of which is open grassland. Today much of it has been transformed into farmland. But, both in the grassland as well as in fields of grain, the Long-tailed Widowbird makes its home. As we drove long distances amidst the farms and grasslands, in the summertime, my father would say, 'Sakabula!' and point them out.
I was always very excited to glimpse a sakabula. From the car, over the open landscape, they could be seen from far away. They generally looked like wisps of sooty black feathers blowing in the wind. From closer it was possible to make them out as birds. A male sakabula in display has a peculiar way of flying. Instead of straightening himself out into a streamlined shape, he seems to do his best to encumber himself. He tilts his long tail downward and spreads out the individual feathers into a vertical fan. He holds his body in an upright position, and keeps his wings above his body, beating them infrequently and erratically. He often seems to make no progress, hovering against the wind, or slowly cruising back and forth over the grass tops. But the one thing he does right, is make himself conspicuous! From close up, it's also possible to make out the bar of white feathers bordering the bright orange-red patches on his upper wings, and to hear his 'swizzling' display call.
The Girls go for the Tails
It is all about attracting girls. Male long-tailed widowbirds hold territories staked out in the grassland. In his territory a male will construct a number of 'proto-nests' – just a small shell of dry grass that the female can later elaborate into a proper nest. But after making the proto-nests he will try to attract the females to complete them. In optimal habitats, the male territories can be spaced 50-150m/yards apart.
So then the males launch into their display flights. The females select their mates, enter the territory of the one they like best, mate with him, then make the nests and lay their eggs. A popular male can attract many females, while an unpopular one may be left with none! The females breed individually in the male's territory, spacing their nests well apart. The nests are usually low down amidst the grass. They are woven of dry grass and lined with fluffy grass seed heads. The female incubates, broods and feeds the chicks all on her own.
It has been proven that a male sakabula's long tail is primarily intended to be attractive to females. As in other animals with sexual dimorphism (a noticeable difference between males and females) the difference comes down to competition between males. In many males, the display features are used to intimidate other males: the most impressive male will intimidate other males away from his territory or his harem of females. In the sakabula, there is some display between males contesting territories, but they don't use their tail-fanning displays in these. After displaying in their territories they will often come together to roost in reedbeds together without fighting. Instead, the tail-fanning display is intended for the eyes of the females. And it is indeed all in the tail. The female widowbirds will select the male with the most impressive tail, then go to his territory and have his babies.
In an experiment, Malte Andersson and colleagues messed with these birds! They took a group of 36 male widowbirds to study. They caught and ringed them. Half of the birds were allowed to keep their tails; one fourth had their tails snipped to a length of a measly 14 cm/5.6"; then the pieces of tail that were snipped off, were glued onto the tips of the tails of the other quarter of the birds, giving them tails over 20 cm/8" longer than normal! Guess which males attracted the most females? Indeed, the widowbird males with tails even longer than what is possible in un-tampered-with reality, attracted the most partners!
This proves the power of female choice. The extremely long tail of the male Sakabula would seem to be against the idea of survival of the fittest. The males deliberately make themselves conspicuous in the breeding season – and not just to the females, but to any raptor in the vicinity as well. His long tail, while not being as cumbersome as it would seem in his elaborate display flight, still gives him a disadvantage compared to a falcon, for instance. Just having to grow the new feathers – and he has to grow longer wing feathers together with the longer tail feathers each season – must be a tax on his body's metabolism and cellular machinery. On the ground, he seems encumbered by being unable to lift his tail while he feeds, the tail dragging around as he hops about. It gives ground-bound predators something to grab hold of. The longer the tail, the more the encumbrance. So … it would seem that by Darwin's standard the male widowbird should never have evolved his extravagant feathers!
So it would seem that female choice can be a more powerful agent of change than factors of success in the environment. But there's much science still doesn't know. Primarily: WHY do female long-tailed widowbirds prefer males with such long tails? This species has the longest tail of all, and there are several widows that never develop particularly long tails, and one must presume that the females of those species don't mind their mates having shorter tails. Or do they?
