Text by Odette Curtis & Ann Koeslag

t’s a typical winter’s morning in the Western Cape – cold, damp, grey. Within the stand of I trees it is dark, almost eerie, as the sun’s rays barely touch the canopy. The sounds of guinea­ fowl awakening from their roost, Egyptian Geese disputing territories and hadedas calling raucously over the forest canopy are all characteristic in this modified environment. I wander deeper into the dark interior of the for­ est and stumble on the evidence of a serial killing: bones and feathers, flecked with dried blood, litter the forest floor. As I stoop to collect the remains of the victims, I become aware that I am being watched. I glance up and there she sits, the silent assassin, perched high above me. Her long tail, slender build, blood-red eyes and aristocratic stance command respect. Her presence is strangely compelling, sinister. She weighs no more than a kilogram, yet here she is queen of the forest, the

Black Sparrowhawk melanoleucos. 

photo access/j.j. brooks black sparrowhawk Foresafrica – birdst & birding 46 flock of Helmeted Guineafowl forage, the hunter must know exactly what she is Aunaware, at the edge of the forest and doing and be in complete control as there her attention slowly shifts to them. She is always a small chance she may receive stares intently at the gamebirds below her a fatal kick from this big gamebird. The and I sense that she is considering taking male Black Sparrowhawk (which weighs one on. But she must choose her moment only about 450 grams) will seldom, if and her individual target carefully as, ever, attempt to take a guineafowl under even though she has the equipment and natural conditions. In most instances, the power to tackle and kill one, a flock of being -hunting specialists, both sexes guineafowl will turn on an attacking prey primarily on doves and pigeons. hawk. A Black Sparrowhawk female typi­ Suddenly I hear a soft ‘chipping’ sound, cally weighs less than a kilogram, while a which grows louder and crisper as every­ full-grown male guineafowl tips the scale thing else in the forest falls silent. The at approximately two kilograms. female perks up, the guineafowl get a This demonstrates the power in this reprieve, and she gives a loud scream as tenacious hawk – the largest breeding she flies in the direction of the call. It is Accipiter in Africa. To tackle a guineafowl, her partner in crime and he has brought food – the ‘chipping’ is his way of alerting her to this. She snatches the Laughing Dove from him and immediately flies up to her nest. Her two chicks are excited by her arrival and crab across the nest struc­ ture, desperate to be fed. They are still small and downy, unable to feed on their own. She becomes a different creature on photo access/j.j. brooks the nest – calmer, gentler as she carefully Above The adult female checks on her well-fed nestlings, now approximately four weeks old. pulls off small pieces of meat and deli­ cately feeds them to the chicks. The sur­ Opposite A juvenile Black Sparrowhawk gorges on its guineafowl kill. prising tenderness with which she does this is engaging to watch. Below Jumping for joy – a young Black Sparrowhawk exercises on the nest, just days away from fledging. Some weeks later I return to the nesting area and am delighted to find the forest eastern and northern reaches of its distri­ floor littered with many more bones and bution. In the Western Cape (and parti­ feathers and to hear a desperate, frantic cularly on the Peninsula), however, more wailing which reaches the far ends of the than 80 per cent of the adult are forest. This calling, although described by melanistic, many of these birds having the daily forest-walkers as resembling ‘a no white markings on their throats what­ baby being murdered’, is music to my soever. It is an interesting pattern, and ears. It is the sound of healthy (but hun­ one that we do not yet understand. gry) fledged chicks, pleading with their To date we have located 23 nests (there parents to bring them food. Although are probably at least another five to 10 they are able to fly well and their feathers pairs) and trapped and marked 20 adults. are fully developed, their hunting skills at All the nests are in alien pine, poplar or this stage leave much to be desired and trees and it is obvious that the they are totally dependent on the adults alien-vegetation clearing initiatives which to provision them. This dependency may are gaining momentum on the Peninsula last two months or longer, until the fledg­ and elsewhere pose a serious threat to lings are forced to learn to fend for them­ Black Sparrowhawk habitat. However, it is selves and face the many hazards that life as well to remember that the species has presents to a young hawk. been able to adapt to exploit these alien trees and make a home for itself in a part of the Western Cape Raptor ‘new’ environment. It is partly for this AsResearch Programme (based at the reason that its numbers and range have Fitzpatrick Institute), we began studying increas­ed dramatically, to the point where Black Sparrowhawks­ on the Cape Penin­ the Black Sparrowhawk can now be sula four years ago. Essentially, the proj­ encountered in many places that were ect entails colour-ringing adult birds and not part of its historical range. monitoring their nests. The melanistic In the past in , it was con­ (black) form is rare in this species in the fined to breeding in large, indigenous  photo access/g.p.l. du plessis nico myburgh

48 black sparrowhawk africa – birds & birding april/may 2004 black sparrowhawk 49 trees (such as yellowwoods, mahoganies Therefore it was either overlooked on and Ficus spp.) in Afromontane forests account of its rarity and its secretive along the south and east coasts. Through nature or it really did not occur on the the years about 45 per cent of this Cape Peninsula. Many ornithologists indigenous forest (and there­ argue that the sparrowhawk is an ‘alien’ fore, sparrowhawk habitat) on the Peninsula and that it has only has been completely de­stroyed managed to disperse into this area and and it is possible that in some proliferate because of its ability to exploit areas alien plantations are ful­ alien trees. filling the much-needed role of But while it is likely that this species these lost trees. occurs on the Peninsula at densities dis­ This is an idea that tends to spark proportionately higher than they would heated debate among ornithologists, have been originally, can we assume that as information about the historical it was never here to start with? The distribution and density of this species Peninsula certainly had some forested in certain areas (particularly the Cape valleys, such as Orangekloof and New­ Peninsula) is scant and raises the ques­ lands, yet little is known about the extent tion as to whether the Black Sparrow­ and composition of these forest pockets hawk ‘belongs’ in certain areas (even if and even less is known about the histori­ they contain indigenous forest) in the cal distribution of in the area. first place. The closest neighbouring forests would How alien tree removal affects raptors probably have been those at Groot­ is a contentious and complex issue and vadersbos, near Swellendam – a fair dis­ one that is increasingly being raised with tance from the Peninsula. But whether reference to Black Sparrowhawks. But this was too far for the birds to disperse to perhaps the inevitable removal of this the Peninsula is debatable. habitat will allow us to learn more about It is conceivable that this hawk did the sparrowhawk. By colour-ringing naturally occur on the Peninsula and that enough adults we will be able to monitor severe deforestation in the late 1600s saw their movements and breeding activity, the destruction of existing nests and the and as the alien-clearing projects prolifer­ decline of the species in the area. A cou­ ate and begin to impact on hawk popula­ ple of pairs may have remained – this is tions, we should learn more about how an elusive bird that is easy to overlook, the birds respond to radical habitat loss. more so in indigenous habitat. Eucalyptus It will pose a number of questions. Are and pine plantations were first cultivated pairs generally faithful to each other and in the mid- to late 1800s. Why the hawks their nest sites? How far do they move to did not respond sooner to this ‘new’ set up a new territory once a nest-tree has habitat is not clear. Perhaps it takes a spe­ been felled? How do nesting densities cies longer to adapt to such a change change as felling increases? How does than one might expect. Alternatively, breeding­ success change with increased with the spread of agriculture and urban­ felling? The results of such research may isation, prey abundance (in the form of also give us greater insight into similar pigeons, doves and large gamebirds) problems happening in more natural eco­ would almost certainly have reached systems (for example, hawks in higher levels more recently and perhaps Madagascan forests). sparrowhawk range expansion has been more closely linked with this habitat earliest known Black Sparrow­ change than with alien tree invasions. The hawk nest on the Peninsula Either way, it is generally agreed that the was recorded less than 10 years ago; prior Black Sparrowhawk is either a fairly recent to that there were almost no records of ‘re-coloniser’ or a ‘new coloniser’ on the breeding activity in the area. The only Cape Peninsula and in adjacent areas. This evidence that this species occurred there may explain certain traits that are unique historically is a single record from Andrew to this population, such as smaller broods, Smith, an early collector, of two imma­ early winter breeding (some nests start as On the Cape Peninsula, the melanistic tures from Wynberg in the 1830s, which soon as March, while in other parts of the morph of this sparrowhawk is more suggests that the bird had bred in the country breeding generally starts in July) common than the white morph, for Cape in the past. (Elsewhere­ in the coun­ and an unusually long breeding season reasons that are not understood. try, it was always described as ‘rare’.) (lasting up to nine months). 

50 black sparrowhawk africa – birds & birding odette curtis to double-brood Attemptshave been re­corded on several occasions on the Peninsula, but all but one appeared to fail during the incubation period. Black Sparrowhawks in KwaZulu-Natal have successfully raised more than one brood per season (one pair raised three consecu­ tive broods). Clearly, the species has the capacity to double- or multiple-brood, but the mechanisms behind this unusual trait are unclear. It is likely that this is largely a function of the artificial abun­ dance of the hawk’s primary food source (pigeons) which has been boosted by man’s changes to the environment through urbanisation and agriculture. The more food that is available to the spar­ rowhawks, the more energy-reserve they have to breed, and the possibility of them raising a second brood thus increases. Both feral and indigenous doves and pigeons have proliferated in cities and they are major attractants to bird-hunting raptors. The Black Sparrowhawk is just one species that has managed to exploit this super-abundance of prey: African Goshawks, Red-breasted Sparrowhawks, and Peregrine and Lanner falcons have odette curtis all responded in a similar fashion. Why to challenge a goose and win – the goose A Black Sparrowhawk nest in a small double-brooding is so rare (despite an is often the victor and the sparrowhawks stand of Eucalyptus trees. This predator extended breeding season) and why it simply have to wait their turn to make has extended its range as a result of its has not been adopted in any of the other use of their own nest. We have often seen ability to exploit manmade habitats. bird-hunting raptors is not known. It is them doing this: a bird (usually the conceivable that this trait would be more female) will perch, either in the nest-tree common on the Peninsula if it weren’t itself or in one nearby, waiting impa­ for interference from a rather large and tiently, while the incubating goose keeps intrusive waterbird… a close eye on her. As soon as the goose Egyptian Geese and Black Sparrow­ has finished making use of the nest, the hawks have probably been adversaries for sparrowhawk will reclaim it. But once a centuries, although this conflict has cer­ nest has been used and abandoned by a tainly become more apparent recently, as goose, it is often so damaged from her both species have responded positively to weight that it collapses and the hawks anthropogenic changes in their environ­ need to build a new one. At other times, ment. The Black Sparrowhawk builds a however, they don’t rebuild the nest and Acknowledgements large, sturdy stick nest, perfect for sup­ therefore do not manage to breed in that We would like to thank Andrew Jenkins for porting the incubating female and later particular season. We suspect that if it introducing us to the first nests on the her two or three chicks until they are weren’t for interruptions of this sort, Peninsula and helping us to develop this almost fully grown. It is also ideal for the more sparrowhawk pairs would fledge project; Geoff Seekings, Sharon Yodaiken, robust and invasive Egyptian Goose, chicks and more might attempt to dou­ Tish Foyle, Peter Ablitt, Nicolas Aitchison, which regularly commandeers sparrow­ ble-brood. Kevan Hearshaw and Kate Sage for their hawk nests. Naturally, no Black Sparrow­ Despised by chicken-keepers and pigeon- much-needed help with finding and moni- hawk would be too charmed by having a fanciers, revered by falconers and raptor­ toring nests; the Cape Bird Club for some big goose take possession of its nest, espe­ philes and sought-after by twitchers, the financial support; and the Raptor Research cially considering the significant amount Black Sparrowhawk is certainly not a bird Foundation for awarding the Leslie Brown of time it takes to build (up to two that has gone unnoticed. To those of us Award to this project. We also thank Peter months). who admire it, every encounter we have Steyn and Ron Hartley for their comments However, contrary to what might be with this black hawk is breathtaking and on this article. expected – that the hawks would be able beautiful. An important top predator 

52 black sparrowhawk africa – birds & birding