Birds are pretty adaptable creatures. They can, and do, make themselves at home in environments that to a greater or lesser degree have been modified to human requirements.
Some species are more confident in these habitats than others and you’ll see them when visiting the local botanical garden or strolling through the grounds of your holiday accommodation. More importantly, perhaps, they could be birds in your own garden, giving you the opportunity to become more closely acquainted with them. In this issue and in the months ahead science editor Tim Jackson takes a look at some of these familiar bird groups, starting with a perennial favourite, the robin-chats.
Part of the reason for the popularity of robin-chats is no doubt their vocal prowess. They are dawn-chorus sopranos, and nothing beats being woken in summer by the song of an aptly named chorister or a white-browed robin-chat before your alarm clock does its duty.
Robin-chats are highly territorial and an adult pair will defend its patch throughout the year. Territories can vary quite markedly in size, depending on their location and the density of birds in the area. Cape robin-chats may guard an area as small as 500 square metres, although in the expanse of South Africa’s southern Karoo territories as large as 10 000 square metres or more have been recorded.
Whereas a Cape robin-chat pair may be seen together quite often, in other species a single bird is more likely to be observed – but that’s not to say that the male and female are not fully aware of one another’s presence. In the dense vegetation the robin-chats inhabit, a pair usually relies on sound rather than sight to stay in touch. This means that white-browed robin-chats, for example, maintain contact by means of sub-songs and chitter-chatter as well as by duetting, during which the female joins in with the male’s song as it reaches its crescendo.
The song can also serve as a warning to other robin-chats to keep off a pair’s patch. The system works well – in white-browed robin-chats the male and the female cooperate to ward off potential intruders, which they typically confront with a barrage of duetting. And if this unambiguous vocal
The red-capped robin-chat can reproduce the calls of at least 40 other bird species, including the distinctive cry of the African fish-eagle
statement is not enough, these feisty little birds point their beaks upward, flick their fanned-out tails and beat their wings in silent warning. Male Cape robin-chats also bombard unwelcome visitors with an outpouring of song, directing their wrath onto other species too as they defend their territories from intrusion by white-eyes, sun-birds, doves and, especially, cuckoos.
Male Cape robin-chats have up to half a dozen favoured song posts in their territory from which they belt out their songs. They sing mostly at dawn and dusk – they are, in fact, quintessential members of the dawn chorus – repeating a series of whistled phrases. Females may sing as well, but only seem to do so in the absence of their mates. This species, like other robin-chats, is a great mimic – one male has recorded copying as many as 36 other birds. Cuckoos, mousebirds, bulbuls, thrushes, shrikes, starlings, sunbirds, white-eyes, canaries and buntings – they all feature in the Cape robin-chat’s repertoire. Of course, while the songs are performed with the serious intent of keeping other birds away, to humans they appear as beautiful melodies that enliven our gardens – in fact, I’m listening to ‘my’ Cape robin-chat as I write this article!
Robin by name, chat by nature
Until their recent name change, robin-chats were known as robins, in southern African circles at least. But they are not really robins at all, being closely related to chats and flycatchers.The name ‘robin’ stems from colonial times when it seems, the British were obsessed with naming any red- or orange-breasted bird in a new country they settled in after their own beloved robin redbreast. In India and Africa, the ‘robin’ is actually a chat, in North America, it’s a thrush, and Australian and New Zealand ‘robins’ are members of the flycatcher family.
The Afrikaans name for robin-chats, ‘Janfrederik’, is said to come from the rhythm of the Cape robin-chat’s trisyllabic alarm note, wur-de-wur, which it also uses when it goes to roost.
But to human ears, there’s more to a robin-chat’s repertoire than just a pretty song; the calls that it copies can reveal to us where it has been hanging out. A chorister robin-chat in Pietermaritzburg, South Africa, was heard to imitate freckled nightjar, bush blackcap and orange ground-thrush songs, which indicated that this altitudinal migrant had spent time in the montane areas frequented by the species it was mimicking.
The most unusual site of a Cape robin-chat nest was an arrangement of dried flowers in the lounge of the Grahamstown Golf Course
For imitating other species, the first prize should perhaps be awarded to the red-capped robin-chat, which can reproduce the calls of at least 40 other bird species, including the distinctive cry of the African fish eagle. It also copies other neighbourhood favourites, such as the yapping of a dog. Chorister robin-chats are great mimics too; their repertoires embrace the calls of the African crowned eagle, blue crane and various frogs, as well as the more urban sounds of people whistling, car alarms and train hooters. One pair in KwaZulu-Natal, South Africa, took mimicry to another level by utilising the duetting call of a southern boubou for their own contact calls. Rüppell’s robin-chats are also noted for imitating whistled tunes.
Whereas the majority of robin-chats are at their most vocal early in the morning and late in the afternoon, red-capped males sing at intervals during the day when the weather is overcast. Within one area, all the males often simultaneously mimic the same bird, then change their calls and imitate another species.
Look up robin-chats in a field guide and you’ll get a good idea of where they fit into the suburban landscape – ‘dense’, ‘evergreen’ and ‘woodland’ are the words likely to crop up. The Cape robin-chat prefers areas with thick cover and trees; the white-browed typically occurs in riverine forest and dense evergreen thickets; and the red-capped likes evergreen forest and woodland.
There’s a good reason for cuckoos not being welcome in robin-chat territories – the red-chested cuckoo is a brood parasite (and) robin-chats are favoured hosts
Fortunately, robin-chats as a group have taken easily to human-inhabited environments, so the chances are good that they will make a home in a garden that has a thick shrubbery and a scattering of evergreen trees that replicate their natural habitat. Water, for both drinking and bathing, is high on their priority list too, and several species like a prominent perch from which they can sing and display.
Once a pair of robin-chats has taken up residence, it is likely to stay for quite some time. These species are relatively long-lived – the oldest Cape robin-chat was recorded as living for 17 years – and a pair often holds a territory for five years or longer. Youngsters can potentially take up a territory from the age of two years, but many are unable to do so because of the high survival rates of the incumbents. If one partner dies, however, the other will probably bond again quite quickly, usually with a non-breeding bird that has been ‘floating’ in its territory. By doing so, the widowed bird is able to maintain its breeding patch in the garden.
Robin-chats make a cup-shaped nest of twigs that line with leaves, hair, moss and the like. In the case of the white-browed robin-chat, though, the structure may be quite rudimentary, consisting of only a pad of rootlets. The nests tend to be located in bushes or dense vegetation, although Cape robin-chats are well known for being catholic in their choice of site and any readily available container will apparently do. The female – for she mainly does the work – may build her nest in a plant pot, an old tin, a tree stump, a hanging basket or a garden shed. She will even make use of an open nesting box if you provide one. Perhaps the most unusual sight of a Cape robin-chat nest was an arrangement of dried flowers in the lounge of the Grahamstown Golf Course.
Surprisingly perhaps, almost all the nests of white-throated robin-chats found have been on the ground, usually at the base of a small tree trunk or vine. Cape robin-chats also seem to prefer a low situation for their nests; more than a third of those discovered were located at ground level.
Robin-chats lay between one and three eggs (usually two or three), with the exception of the red-capped, which is the only species known to produce four eggs in a clutch. Cape robin-chats, too, are unusual in that they can breed more than once in a season. Incubation – again the female’s job – lasts about two weeks, and the chicks fledge two to three weeks after hatching. Both parents take on the task of feeding them, for some six weeks in total, and both will defend the nest bravely, attacking snakes such as boomslangs or Cape cobras that venture within range. White-browed robin-chats are also known for becoming quite aggressive towards other birds during the breeding season.
There’s a good reason for cuckoos not being welcome in robin-chat territories – the red-chested cuckoo is a brood parasite that deposits an egg into a host’s nest.
There’s a good reason for cuckoos riot being welcome in robin-chat territories – the red-chested cuckoo is a brood parasite that deposits an egg into a host’s nest.
Robin-chats are favoured hosts, and they incubate the ‘foreign’ egg even though it is somewhat larger than their own. The young cuckoo hatches a few days before the robin-chat chicks do and tips them out of the nest as they, helpless, emerge from the eggs. Constantly begging for food, the cuckoo chick grows very quickly and within about 10 days it can be twice the size of its foster parents. The size difference is so extreme that the hard-pressed robin-chats can end up sitting on the back of ‘their’ enormous offspring as they feed it!
Robin-chats feed largely on insects and other invertebrates, including spiders, centipedes and earthworms, although they may add other small fries, like tiny frogs and reptiles, to their diet. Some species, notably chorister, Cape and red-capped robin-chats, eat berries as well. Most of them forage on the ground in leaf litter, flicking through plant debris in their search for food, but they also glean insects from foliage and tree trunks and sometimes hawk termite alates. Chorister robin-chats look for prey in the mid-stratum of trees too and move into the canopy to feed on berries.
In the garden, accumulated leaf litter not only acts as a mulch for plants but provides ideal foraging conditions for robin-chats. During weeding or plant-clearing activity, Cape robin-chats in particular pay close attention as the soil is disturbed in the hope that insects or worms will be exposed. They also have a reputation for raiding the larder – quite literally – boldly venturing into houses in search of food scraps. Not even the dog’s bowl is immune; the intrepid birds readily help themselves to leftovers.
Being mainly insectivores, robin-chats also eat fatty or meaty foods, and mealworms, bone-meal and suet are good options for attracting them to the bird table. In my garden they are partial to the bones half-eaten by our dogs, picking off bits of meat and marrow, and presumably a few insects too. I regularly ask our local butcher for the scraps from the meat saw – the mixture of bone, fat and marrow is a sure winner. Grated cheese is reputedly a favourite bird-table food too, and Cape robin-chats also eat porridge.
As these are birds that typically forage in the undergrowth, they are more likely to be attracted to a feeder or table placed low down. All robin-chats will use a bird-bath, although Rüppell’s has a reputation for chasing other garden birds away from this favoured resource.
On the whole, robin-chats need little encouragement to spend time in suburban gardens and it’s impossible to not enjoy the presence of these attractive, vocal birds.
