Variations on a Theme
Text: Tim Jackson. Photographs. Various. Article from the June 2013 issue of Africa Geographic Magazine.
Nothing if not variable, starlings are a bit of a mixed bag. Some definitely have an affinity for the urban environment, whereas others are true country bumpkins; some spend most of their time in treetops, but others prefer a carpet of lawn. There’s no such thing as a ‘typical’ starling, their looks aside, each species has idiosyncrasies that distinguish it from the flock.
As garden birds, some starlings are more familiar than others. Africa boasts roughly 50 species in total, almost all of which are described as ‘common’ or ‘locally common’ in field guides, so there’s a good chance you’ll be acquainted with quite a number of them. There are the red-winged, wattled, greater blue-eared and violet-backed, for instance, which range all the way from southern to East Africa. And then there are the more localised species, like Cape glossy, Burchell’s and African pied in the south, Rüppell’s, superb and Hildebrandt’s in the east, and the splendid and purple glossy starlings of West and Central Africa.
The cheerful whistles of red-wings are frequently heard in many city environments, but few other species are so accustomed to the bright lights. Some seem happier enjoying the quiet life of a small-town setting, and others rarely take up residence in suburbia at all. Take the chestnut-bellied starling of Sahelian Africa for example, which only ventures into villages and sometimes towns without becoming a garden regular. Pied starlings tend to shun built-up areas too, although they may be common in small rural towns. Another hanger-on to the outskirts of the larger conurbations is the violet-backed starling, whose vivid coloration enlivens many a garden, but only on the outer fringes of suburbs.
Starlings show similar variation when it comes to food and their feeding habits. Insects and other invertebrates make up a major part of their diet, but fruits are important too. Violet-backed starlings are particularly partial to fruits – especially figs – so a fig or other fruiting tree in the garden would be a huge attraction. When fruits hang heavy on the branches or vines, you can be sure of a sudden influx of starlings, especially red-wings, but once the feast is over they will disappear as quickly as they arrived. In fact, any abundance is enjoyed; greater blue-eared starlings and Cape and splendid glossies, for example, are quick to take advantage of termite emergences.
Although Cape glossy starlings tend to prefer insects, they are also partial to nectar, so flowering aloes in the garden are sure to attract them. Red-wings are well known for delving deep into protea flowers in their quest for nectar – and emerging with a bright blush of pollen. These relatively large starlings are unusual within the family in that they catch small lizards and even nestlings from time to time. They are also known to use a hard ‘anvil’ on which they break up large food items such as millipedes before feeding them to their chicks.
In East Africa, Hildebrandt’s starling is atypical in that it eats seeds as well as the fruits and insects that make up the diet of other starlings. (It also bucks the trend by roosting in a tree hole at night, unlike many other members of the group, which roost communally when not breeding.) Like Rüppell’s and superb starlings, it feeds mainly on the ground, so open expanses of lawn will suit these species.
Given starlings’ feeding habits, a smorgasbord of bone-meal, suet, mealworms and fruit will attract them to a feeder. Not that these opportunistic birds restrict themselves to what is deliberately put out for them; when enjoying breakfast in the garden, I’ve learned not to leave my meal unattended or I will return to find Cape glossies making short work of the bacon and eggs!
The ‘common’ species
In addition to its extensive tally of indigenous starlings, Africa hosts two relative newcomers, both of which have settled in South Africa: the common starling introduced to the south-western Cape from Europe in 1899; and the common myna, which arrived in two waves from Asia.
Common starlings are abundant in southern South Africa where they gather around human habitation, sometimes in huge – and messy – flocks. Urban structures offer them good nest sites under eaves and in pipes and gutters, and the pushy birds will also take over nesting logs if the entrance hole is large enough. They’re aggressive when feeding too, chasing other birds off the lawns where they forage and off bird tables as well.
There’s not one but two common mynas in South Africa: subspecies Acridotheres tristis tristis, which was introduced to Gauteng from India and Sri Lanka in about 1938, and A.t tristoides, an immigrant to Durban from Nepal, Burma and northern India in the late 1800s. Like common starlings, the mynas are adaptable and drawn to human settlements, and outside the breeding season they aggregate in large groups, forming substantial communal roosts at night.
The birds pair for life and are highly territorial when breeding, aggressively chasing off other birds – especially other mynas – and even people. Other hole-nesting species, such as green wood-hoopoes, find themselves ejected if they happen to have occupied a natural hole in a tree first, but the mynas will also assemble their nests on buildings and other man-made structures, adding plastic, paper, cloth and string elements to an untidy mass of grass, twigs and leaves.
Like common starlings, common mynas are often seen patrolling lawns. They are wary of humans at bird tables, but drive other birds away to ensure that they get the best tidbits. For their bullying habits and propensity for ousting other bird species, particularly in the urban areas where they prevail, mynas are widely regarded as a pest They’re a successful pest though, and their range across South Africa continues to increase.
Dad look-alike. Unlike most juvenile birds, which take after their mothers, newly fledged red-winged starlings resemble their fathers.
Many species appreciate a quiet part of the garden with minimal human disturbance, especially if they are likely to nest. Most starlings breed in natural tree hollows and as such sites are at a premium in gardens, the birds will often move into the second-hand nest of a barbet or woodpecker. Of course, a strategically placed hollow sisal log or a nest-box with an appropriately sized entrance hole would do too. Some species, notably Cape glossies, have been known to nest even in metal pipes and post-boxes.
Red-winged starlings are the exception to the hole-nesting norm. In its natural habitat this species frequents rocky outcrops and gorges, where it builds a large, flat nest of twigs, grass and rootlets on a ledge. In an urban setting, the beams, windowsills and other niches of multistorey buildings, and even creeper-covered walls, are a handy substitute.
Also different are superb starlings, which build an untidy domed nest of twigs, usually in a thorny tree or bush. The nest often has a tunnel leading into it, and if it is situated in a tree that is not thorny, the birds construct a prickly barricade of twigs around it. Rüppell’s starlings enjoy the best of two strategies, often breeding in holes, but sometimes building nests of thorny twigs in trees.
Most starling species lay two or three eggs in a clutch, although some, including the greater blue-eared, may produce as many as five. Incubation lasts for about two weeks, and it is generally done by the female, although male redwings tend to be a little more accommodating towards their partners and spend some time on the nest. Superb starlings again deviate from the norm in that there may be a one- to two-day interval between the production of each egg and the female begins to incubate the clutch roughly when she lays the penultimate one. This means that the development of the chicks is staggered and those that hatch later may not survive.
In all species both parents feed the chicks in the nest and later when they have fledged, but in some cases they are helped by other birds, usually their older offspring. Cape glossy starlings are good example of this cooperative breeding, with as many as six individuals bringing food to the chicks. Often, though, the female takes the items from the helpers before passing them on to her latest brood. One dedicated Cape glossy has been recorded contributing to another pair’s breeding efforts for four consecutive seasons.
Unlike most other starlings, Rüppell’s adults hold a stable territory not just for breeding but throughout the year. They do, however, tolerate their own offspring within the territory for at least two years, albeit at the outer margins while they are nesting. Sometimes these starlings breed cooperatively which suggests that the tolerated youngsters play a role in feeding the next generation.
As extroverts of the bird world and whistlers of note, starlings are hard to miss. And with their attractive appearance – enhanced in many species by a glossy sheen to the plumage – they make striking additions to any complement of avian garden visitors.
All together now
When it comes to breeding, the aptly named superb starling does things a little differently. It’s not only cooperative in its breeding habits – a pair may enlist the aid of as many as six helpers to cater for its brood, a trait not altogether unusual among starlings – but it’s also gregarious. There are records from Kenya of six pairs nesting together, each female laying eggs in her own dome-shaped structure of twigs.
And then it becomes complicated. Each pair ropes in not only its own offspring (which themselves may have fledged only a month before) to help feed the nestlings, but also any unpaired males in the group. They’re a pretty altruistic bunch – even a paired male may help another couple to feed its chicks while waiting for his own progeny to hatch, and parents whose offspring have fledged will often help to provision the chicks of other group members in addition to their own.
It’s a successful production line, as proven by a record of six females in a group nesting at least 22 times in total over a 10-month period – one even laid no fewer than six clutches in that time! (Other starling species will have perhaps two broods in a season.) The males remain in their natal groups, whereas the females disperse when they are about a year old.
There’s cheating going on too. After a female has laid her eggs she sometimes ignores her mate and copulates instead with any dominant male in the vicinity.
Video: Submitted by Avi Birds Common Starling [Sturnus Vulgaris]
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