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For its size, the Cape has more plants species including endemic ones, than any other area in the world. Yet its bird life has often been described as dull poor or even in typical high brow scientific jargon "depauperate"!!! Such descriptions have persisted at least since the 1870's (Shelley 1875 Ibis 60) and right to the present day (Harrison et al 1997 The Atlas of Southern African Birds). Sadly the unique Cape Floral Kingdom is under severe threat today. The demands of agriculture, commerce, housing and more recently some forms of leisure and tourism have led to large scale destruction of precious natural vegetation. Ironically the demise of the fynbos has been accompanied by the improvement in our bird life. Consider the facts the authors of the Atlas of Birds of the Southwestern Cape 1989, claimed that 32 bird species had decreased in numbers or forsaken the SW Cape altogether over the last 2 hundred years. On the other hand in a rather incomplete list at least 85 birds are shown to have extended the ranges or numbers over the last hundred or so years. New arrivals outnumber the species that are thought to have become locally extinct by at least 2 to 1. If changes were to continue at this rate, depauperate inappropriate as it might have been even when it was written will soon become depauperised. Deliberate attempts to improve the Cape bird life started early. Already a century ago in about 1898, Cecil John Rhodes, indomitable and irreverent imperialist, ambitiously sought to further extend the home country influence at least to his imposing Groote Schuur estate on the slopes of Table Mountain when he released hundreds of birds of six well known English species there. Rhodes's Rooks, Nightingales, Blackbirds, Song Thrushes and Chaffinches proved themselves poor colonists. The first 3 species must have perished quickly, the Nightingales perhaps somewhere over the southern Atlantic as they set off on their annual ancestry southward migration! The Song Thrushes and Chaffinches bred successfully and managed to establish a tenuous claw hold. The thrushes persisted until about 50 years ago and the Chaffinches are of course still found here in a few scattered localities in the Southern Peninsula. The European Starlings
that Rhodes had brought to the Cape, were however a flyaway success.
Today they are found virtually throughout South Africa. During the
CBC atlas project in the 1980's the starlings were the 6th most
recorded bird. On account of the starlings alone, we must presumably
conclude that Rhodes experiment in avian social engineering was a success.
European Starling Perhaps little known, Rhodes was the father of the progressive and highly profitable Cape fruit industry. At one time he owned more than 30 farms in the Paarl and Stellenbosch districts on which he set out to establish a scientific fruit culture. This industry has led to much altered land uses in the Cape. It gave rise to the building of a network of irrigation dams and together with commercial forestry the planting of (pines, poplars, blue gums, wattles etc) on large scale as in the case of the orchards, windbreaks. Significantly Cape bird colonists owe much of their recent success to the resultant spanning of previously waterless and treeless areas. Apart from the starling, the most successful and spectacular of the pre 1948 arrivals were respectively the Cattle Egret and the Blacksmith Plover. According to the Cape Bird Atlas both are now amongst the 14 or so most recorded species in the SW Cape. The Cattle Egret has literally conquered the world from its tropical African ancestral home and is today found in southern Europe, North and South America, Asia, Australia and New Zealand. With hindsight its arrival in the Cape in the 1930's was probably a small step for the tireless international colonist. As late as 1900 the Blacksmith Plover had not been reported south of the Orange River. It nonetheless reached the southwestern Cape by 1939 and was found to breed here by the late 1940's. Non migratory, the southern and westward extensions of its range was aided by the construction of farm dams and the impoundment of many seasonal streams and rivers in the Karoo areas as part of the state aided campaign to eliminate wasteful soil erosion in the early part of this centaury. Although it normally breeds in close proximity to fresh water feeding occurs over a wide range of short grassland habitats particularly well irrigated lawns, sports fields, golf courses and such like. Recently it has been seen along the seashore yet a further example of this species adaptability.
Blacksmith Plover Another conspicuous recent arrival that benefited from the same conditions that brought the Cattle Egret and Blacksmith Plover to the Cape 30 or 40 years earlier is the Hadeda Ibis. Why the westward expansion of the Hadeda's range should have come only so much later is difficult to explain. Once it had started in the 1970's it was nontheless no less rapid and by the late 1980's the SW Cape and adjacent Karoo areas had pretty much been taken in, albeit sparsely. Significantly the status of all four Ibis species found in the southern Africa has changed in the SW Cape. In line with the overall score I quoted above for winners and losers three are now new colonists or have increased in numbers and one has disappeared. The Sacred Ibis has probably always been found in the Cape, but now in much greater numbers than before, whereas the Glossy and Hadeda Ibises are recent breeding arrivals and still increasing. Only the Bald Ibis now restricted to the Drakensberg escarpment disappeared altogether. It might never have bred in the Cape but was possibly at least an occasional visitor here 200 years ago when its breeding range still included much of the eastern Cape.
Sacred Ibis The afforrestation of the SW Cape whether as a by product of the fruit industry or through commercial plantations, urbanisation and the accompanying gardens and parks or the uncontrolled invasion by alien species of fynbos and strandveld areas, has allowed a number of species to expand their ranges or numbers in the SW Cape. Although tall fynbos indigenous riparian vegetation supports species such as the Rameron Pigeon, Olive Woodpecker, Olive Thrush Cape Batis, and Paradise and Dusky Flycatchers to name a few, they are now also commonly or at least regularly seen in the alien vegetation and particularly gardens and parks. I have no doubt that compared to 50 years ago these species are more common in the Cape. Other beneficiaries have been the Acciiter hawks. Not only has the Redbreasted Sparrowhawk extended its range and numbers in the Cape but the African Goshawk and recently the Black Sparrowhawk have newly colonised the SW Cape. As late as 1979 when the last CBC checklists of SW Cape birds was published the goshawks had barely made it into the main list on the basis of a few then recent sightings whereas the Black Sparrowhawk was still, in spite of a recent Stellenbosch sighting firmly stuck in the list of extinct and doubtful species, old records and escapes on the basis of a specimen from the Cape Division from the early 19th centaury. Today both species are widely found where there are large trees, even in well built up areas. One of my lasting impressions of the African Goshawk is of sitting in church in central Stellenbosch on a fresh spring Sunday morning and in addition to the sermon listening to the excited calling of a goshawk outside.
Black Sparrowhawk With the sad exception of the vultures, African Marsh Harrier, Marsh and Grass Owls and possibly the very large eagles our raptors both diurnal and nocturnal are probably better off today than 50 or 100 years ago. Apart from the Accipiter species already mentioned at least another 4 species have joined the list as breeding species in the Cape, viz. Booted Eagle, Forrest Buzzard, Gymnogene and Giant Eagle Owl. The Hobby too is now regularly seen in and around Stellenbosch, as a non breeding summer visitor, and frequent sightings of the Brown Snake Eagle have led to speculation that it too may breed in the SW Cape. It is interesting that for all these species with the exception of the Gymnogene there are old 19th centaury specimens or sightings from the Cape. Factors such as altered land uses, afforestation, urbanisation with high rise buildings and large inner city feral pigeon populations and quarrying have all contributed to increase in the numbers and ranges of many of the other raptors resident and migratory of the Cape. There are interesting enigmas. Take the Booted Eagle until the late 1960's this small eagle was thought to be a non breeding paleartic migrant to the eastern and northern pans of southern Africa. Its presumed occurrence in the Cape was based on two 19th century records one from Rondebosch in 1828 and another from Clanwilliam. Then, suddenly, mainly through the efforts of stalwart CBC members the Martin family, from Somerset West, bird watchers were alerted to the fact that Booted Eagles were indeed to be commonly seen in summer in the drier mountainous areas of the SW Cape and by 1975 its presence as a breeding species had been confirmed. Had the Booted Eagle been overlooked for many years? Was it perhaps misidentified? Steppe Buzzards are so numerous in summer that few bird watchers probably bother to lift their binoculars at yet another small brown hawk as some observers suggested when they were made aware of the presence of the Booted Eagle. Last century specimens and a breeding record early this century were even erroneously ascribed to the similarly sized Ayres Eagle. It is unlikely therefore that the Booted eagle is a new (late 20th century) breeding arrival. Yet it might have become more numerous in the late 1960's and therefore more notable. If so what caused the increase in numbers? There are no obvious factors such as a favourable habitat change or such like. Commentators have suggested that the Booted Eagle is another example of a former paleartic breeding and migratory species recently establishing a South African breeding base with reverse migration i.e. breeding in the south and migrating to the north in the non–breeding season. Others would be the White Stork and European Bee–eater. For the time being the case must rest on the basis of the Booted Eagle simply having been overlooked. Yet it raises interesting questions. If such a large and obvious species was overlooked could it be that the 19th century records of the African Goshawk, Black Sparrowhawk and Giant Eagle Owl suggest that we have also overlooked these until recently? It is possible, but then again habitat changes have favoured a range expansion by these species. But it is not only the large and bold, that might, have been overlooked. The ornithological highlight of 1996 was undoubtedly the discovery that the Leach's Storm Petrel, an otherwise marine species about the same size of a Laughing Dove was breeding on Dyer's This was the first confirmed breeding record for the southern hemisphere. As it has also been recorded from a number of other off shore islands over the years including Dassen Island, it was probably overlooked before. Breeding Storm Petrels are largely nocturnal and there is thus the same excuse for those intrepid seabird lovers who missed this interesting bird during the months and years they have spent on our off–shore islands working towards their Ph D's and what else! There are also other enigmas in the alleged recent range expansions. Few Cape bird watchers will not be familiar with the trumpeting call of the Pied Barbet. For the 1960's and most of the 1970's when I was cutting my teeth as an aspirant birdwatcher in the SW Cape, the barbet was rarely heard or seen west of the Hottentots Holland Mountains and south of the Olifants River. Yet it was not unknown near Cape Town as earlier editions (1955 and 1963) of the CBC Checklist of Birds of the Southwestern Cape recorded. In 1936, Dr Leonard Gill described it as "scarce near Cape Town". It then became markedly common during the late 1970's and 1980's. Although my experience would not be unique, I found it breeding along the Berg River near Piketberg in the mid 1970's in a willow tree and at Yszerfontein on the west coast in the early 1980's in a sisal and heard and saw it periodically in Stellenbosch in the mid 1970's. In 1986 I enticed a pair to excavate a nest in a dead sisal log in our garden in the Bottelary Hills between Stellenbosch and Kuils River. Based on the greatly increased rate of sightings of this species in the SW Cape in the early 1980's commentators postulated an ongoing range expansion for this species and studies and articles to this effect appeared.
Pied Barbet This might have been so but it would also appear to me that it has virtually disappeared again from these allegedly newly colonised areas in the late 1980's and certainly the 1990's. The Pied Barbet is essentially a dry country Karoo species from time to time do, especially in the prolonged dry periods of below average rainfall, temporarily invade the SW Cape. If so it illustrates another aspect of our ever changing Cape bird life, namely the effect of fluctuating weather patterns. In a way it is almost reassuring to think that not all changes to our bird life are man made! Drought elsewhere may lead to a sporadic influx of Karoo species such as Pied Barbet, Black Korhaan, Namaqua Dove, Namaqua Sandgrose, Dusky Sunbird, Larklike Bunting and perhaps Brown Snake Eagle from further afield. A few may even attempt to breed but generally once conditions normalise, they disappear or become scarce again. Sadly man is now also affecting the weather and we are increasingly being warned of longer term climatic changes such as global warming. Land use changes favourable to range expansions and increased bird numbers have probably now reached an optimum. This means that apart from the negative effects of the direct persecution and disturbance and habitat destruction, climatic changes may become the next dominant factor that will influence bird distribution and numbers in the years to come, be it directly or indirectly through changes in vegetation available, food, etc. May we welcome the likes of the Knysna Lourie, Narina Trogan, or even the Angola Pitta to the Cape Town suburbs? Although we would not normally see the weather or climate as being under human control and this is certainly true for the short term weather changes, mans domination of the natural environment has become so complete and all pervasive that few if any of the changes to our bird life over the last one hundred years or so cannot directly or indirectly be related to human factors. Natural changes in any event probably happen so slowly that we would not really notice them that easily compared to the changes that can be brought about through human agency. Perhaps the Lesser Honeyguide can claim that man has only indirectly aided its range expansion. Conventional wisdom has it that it followed its host the Pied Barbet into the SW Cape. Elsewhere in the southern Africa, the respective ranges of the honeyguide and barbet, do not however always overlap. It is also likely that the temporary increase in barbet numbers in the late 1970's and 1980's was from the Karoo areas to the north and north east. Less conspicuous than the barbet, another potential host in the form of the Olive Woodpecker with a range largely coterminous with that of the honeyguide, at least in the eastern parts of South Africa, has benefited from the relative afforrestation of the SW Cape. I have so far concentrated on the birds that have either expanded their ranges to reach the SW Cape or were successfully introduced to the Cape or become noticeably more common on the SW Cape. The opposite is also true, namely, that again through human intervention, a number of species have apparently disappeared from the Cape or have become much rarer. At least a dozen or so species that formerly occurred here are no longer regularly found and another 20 or so have declined in numbers since the early 1800's. Those that have disappeared are mostly vultures, eagles, or large ground living birds (Wattled Crane) which with the exception of the Egyptian and Bearded Vultures, probably even before the arrival of European and Asian colonists, rare and marginal in the Cape. Their presence in the Cape was confirmed by no more than the odd 19th century collected specimen or sight record. Sad as the demise of these attractive and spectacular species was, it was probably inevitable given their marginal status in the Cape.
Cape Vulture Blue Crane with chick Interestingly too, some of these magnificent large species, once rare and marginal have enjoyed a revival due to favourable factors. The White Pelican is probably more numerous today than 50 or 100 years ago. The White Stork and the Blue Crane although surprisingly omitted in the Cape Bird Atlas from the 85 beneficiary species that I referred to above have become markedly common in the agricultural areas of the SW Cape. The wheat growing region around Caledon, Bredasdorp and Swellendam has become the stronghold for both species in southern Africa. Others might have enjoyed a temporary revival only to again become rare and marginal. The Secretary Bird may be an example.
White Pelican Rare in the SW Cape, anecdotal evidence would suggest that the Secretary Bird has become even scarcer in recent years. Yet, I am almost convinced, that it never occurred regularly in the mountain fynbos, west coast strandveld and renosterbos areas of the SW Cape where it has now allegedly become so rare. The historical distribution of these vegetation types vastly reduced in size, would have covered all the area west of the Hottentot Hollands / Grootwinterhoek Mountain ranges. The Secretary Bird is a terrestrial predator that requires sturdy trees or bushes for roosting and nesting. Climax fynbos, strandveld and renosterbos would not have permitted effective ground hunting and generally lacked adequate roosting and nesting site. It is possible that the Secretary Birds only sparsely colonised these areas after these vegetation types had been much altered by agriculture and more frequent burning. Alien trees would have provided breeding sites. In thirty years of bird watching in the Cape, I have only seen half a dozen or so Secretary Birds west of the Hotentots Holland. All were in agricultural habitats and around Stellenbosch only in either young or fallow vineyards. The only nest I have seen in the Cape was in an exotic pine tree and in older breeding records from Faure was also for a nest in a pine tree. It is my guess that the Secretary Bird was always rare and localised or even at best a straggler in the SW Cape but that agricultural activities including the frequent burning of natural vveld and the planting of exotic trees (pines in particular have led to breeding pairs establishing themselves in a few scattered localities. Lately persecution, more intensive farming practices and the pressures of higher human population densities have driven these pairs away. To the east and further north, in adjoining Karoo areas, Secretary Birds continue to occur regularly albeit it sparsel
African Marsh Harrier Black Oystercatcher Many birds have suffered from human activities. Direct persecution disturbance Black Oystercatcher and the introduction of terrestrial predators, to off shore islands, off road vehicles, people and dogs along our coastline, the destruction of specialised habitat via the; African Marsh Harrier and wetlands and competition for food are ongoing threats. The once healthy populations of Jackass Penguins numbering perhaps millions has crashed spectacularly mostly due to over fishing. No doubt many birds will continue to suffer on account of the increased human pressures of development and competition for shared resources. Our bird life has changed rapidly in composition and numbers over the last 50 years virtually all due to human activities. All in all these changes have meant an improvements in the number of species and of individuals. I wonder whether the founders of the CBC would have predicted this 50 years ago. It is true that whenever
we prophesy the future of our natural environment we tend to err on
the side of despondency. Birds are wonderfully adaptable and whilst it
may be considered vastly optimistic to now predict that in
another 50 years time the winners will again outnumber the losers by 2
to 3 or 1, do not be surprised if birds of a great number and variety
continue to be with us. For the rest birds will flourish, because and in spite of us.
Jackass Penguin (Photographs by C.J.Uys, Peter Steyn, Ann Koeslag, Jeremy Keyser and some unknown).
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