New Birds in Africa New Birds in Africa
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1 2 3 4 5 6 7 NEWNEW BIRDSBIRDS ININ AFRICAAFRICA 8 9 10 11 The last 50 years 12 13 Text by Phil Hockey 14 15 Illustrations by Martin Woodcock from Birds of Africa, vols 3 and 4, 16 reproduced with kind permission of Academic Press, and 17 David Quinn (Algerian Nuthatch) reproduced from Tits, Nuthatches & 18 Treecreepers, with kind permission of Russel Friedman Books. 19 20 New birds are still being discovered in Africa and 21 elsewhere, proof that one of the secret dreams of most birders 22 23 can still be realized. This article deals specifically with African discoveries 24 and excludes nearby Madagascar. African discoveries have ranged from the cedar forests of 25 northern Algeria, site of the discovery of the Algerian Nuthatch 26 27 (above), all the way south to the east coast of South Africa. 28 29 ome of the recent bird discoveries in Africa have come case, of their discoverer. In 1972, the late Dr Alexandre 30 Sfrom explorations of poorly-known areas, such as the Prigogine described a new species of greenbul from 31 remote highland forests of eastern Zaïre. Other new spe- Nyamupe in eastern Zaïre, which he named Andropadus 32 cies have been described by applying modern molecular hallae. The bird has never been seen or collected since and 33 techniques capable of detecting major genetic differences Prigogine himself subse- quently decided that 34 between birds that were previously thought to be races of the specimen was of a melanis- 35 the same species. The recent ‘splitting’ of the Northern tic Little Greenbul Andropadus 36 and Southern black korhaans Eupodotis afraoides/afra of virens, a species with a 37 southern Africa is one example. wide distribution in equato- 38 In terms of ornithological discovery, these two ways of rial West and central Africa. 39 describing species are subtly different: the former involves Interestingly, and 40 the discovery of birds we did not even know existed, the rather surprisingly, the 41 latter to birds that we did know about but did not recog- 42 nize for what they were! 43 This article is con- 44 cerned with ‘exploratory 45 discoveries’, and, in this cat- 46 egory, Africa has yielded many sur- 47 prises in the last 50 years, averaging almost 48 one new species a year. Some of these have come 49 from unexpected places – the Ibadan Malimbe was 50 found on lands immediately adjacent to Ibadan 51 University! Another, the Algerian Nuthatch, was dis- 52 covered in 1976 within the boundaries of the western 53 Palearctic – the first species to have been discovered in Prigogine’s Greenbul (left) of Zaïre was not seen 54 between 1982 and 1993 and is under severe threat this region since 1886. 55 from forest destruction. The Liberian Bulbul (right) was described from a Not all ‘new’ species that have been described have sur- mummified specimen found near Zwedru, Liberia, in 1984. It is also under 56 vived the depredations of sceptical taxonomists or, in one severe threat and has not been seen in recent years. 57 1997 – VOLUME 2, NUMBER 1 NEW BIRDS IN AFRICA 39 1 scribed) species; the lighthouse casualty remains the only 1 2 record of the presumably migratory Red Sea Cliff 2 3 Swallow. 3 4 Among the resident birds, forest-dwelling species have 4 5 figured prominently, comprising 61 per cent of the total. 5 6 Some of these are very poorly known indeed – Prigogine’s 6 7 Nightjar and the Kibale Ground Thrush, for example, 7 8 have not been seen since the original specimens were col- 8 9 lected. The one and only specimen of Congo Bay Owl was 9 10 collected in the Itombwe Mountains of Zaïre in 1951. 10 11 Apart from a possible sight record from Burundi in the 11 12 1970s and a record of an unknown owl call in Rwanda in 12 13 early 1990, this species was not recorded again for 45 13 14 years. It was ‘rediscovered’, and one female was caught, 14 15 ringed and released, in the Itombwe Mountains in May 15 16 1996. In contrast to these, some recently discovered spe- land. The site of the discovery of the Kilombero Weaver 16 17 cies are locally quite common. These include the White- as recently as 1990, this swamp is geographically isolated 17 18 throated Mountain Babbler of highland Cameroon, the and is unusual in that even though it is more than 300 18 19 Gola Malimbe and the Udzungwa Forest Partridge – kilometres from the coast, it lies at an altitude of only 19 20 although the partridge may already be threatened by 250 metres above sea level. The same swamp is thought 20 21 specimen collecting. to contain two new, but as yet undescribed, species of cis- 21 22 The Red Sea Cliff Swallow is known from a single specimen that died Surely, however, one of the most bizarre tales of recent ticola. 22 23 when it flew into a lighthouse in the Red Sea, off the coast of Sudan. discovery must be that of the Bulo Burti Boubou from It is probably a reasonable assumption that new species 23 24 Somalia. This bird was first observed in the grounds of a found in the future (by exploration rather than in the 24 25 hospital at Bulo Burti on the Shabeelle River, Somalia, in The Gabela Akalat (above) and the White-headed Robin-Chat (above laboratory) will be highly range-restricted. A glance at the 25 right) were described from Angola within two years of one another. The 26 rate at which new species are being discovered in Africa has August 1988. On 5 January it was caught in a mist-net map of recent discoveries indicates a startling lack of new 26 robin-chat has a fairly wide distribution, extending into western Zaïre, 27 remained fairly constant. Between 1946 and 1955, 10 new and taken into captivity. It was subsequently transported but the akalat is restricted to relict forest patches on the western Angolan birds from the forested regions of the Congo Basin, even 27 28 species were described. The following three 10-year periods to Germany when the person caring for the captive escarpment and is threatened with extinction. though this area is flanked by new species on three sides. 28 29 saw totals of seven, eight and 13 species respectively. In 1976, Leon Lippens and Henri Wille (Les Oiseaux de 29 30 Between 1986 and 1995, another eight new species came to Zaïre) wrote ‘we are convinced that new species of birds 30 31 light. bird was evacuated because of civil unrest. More than a still remain to be discovered in Zaïre’. Right they were: 31 32 The geographical distribution of the 46 species described year later, in March 1990, the bird was returned to 32 33 since 1946 is far from even. Ninety-three per cent of dis- Somalia, and was released back into the wild on 23 March 33 34 coveries have been in the tropics, and 70 per cent of the in the Baclad Nature Reserve: neither it, nor any other 34 35 total have been from within 10 degrees latitude of the Bulo Burti Boubou, has been seen since. The boubou 35 36 Equator. The country that has contributed most to new made additional ornithological history in being the first 36 37 discoveries has been Zaïre, with eight, followed by Liberia, instance in which a bird species has been described with 37 38 Cameroon and Ethiopia, each with four. Somalia, Kenya, DNA and a few feathers as the type material. 38 39 Uganda and Angola have each contributed three, Nigeria a The tendency for birds to evolve into new species is 39 40 further two, and another nine countries have contributed greatest when populations become isolated from one 40 41 one species each. Most new birds have come from the east another. Island populations are classic examples: the 41 42 of the continent, with an impressive contribution of no majority of the world’s highly range-restricted species are 42 43 fewer than six new species from in and around the found on islands. Worthy of note here is that the majority 43 44 Itombwe Mountain forests of eastern Zaïre. of species which have become extinct in the last 400 years 44 45 Nearly all the new discoveries have been of resident, were island species. 45 46 rather than migratory species, with two exceptions. The One could therefore predict that highly range-restricted 46 47 Mascarene Shearwater was described from a beached species on the mainland will be found in situations 47 48 specimen collected in Durban, South Africa, but its breed- which are analogues of islands, such as forested moun- 48 49 ing grounds almost certainly lie well to the north-east of tain peaks and isolated wetlands. The new birds of the 49 50 here, possibly in the Comoro or Mascarene Islands. The last 50 years support this conclusion – two or more new 50 51 discovery of the Red Sea Cliff Swallow was the result of a birds have been found on Mount Nimba in Liberia, 51 52 single bird flying into the Sanganeb Lighthouse, off the Mount Kupé in Cameroon, the Itombwe Mountains of 52 53 coast of Sudan in the Red Sea. To mark its misfortune, it eastern Zaïre and the Udzungwa Mountains of southern 53 54 was given the scientific name Hirundo perdita, the ‘lost Tanzania. Intensive searching (or a bit of luck!) in the 54 The Sokoke Scops Owl (above right) is locally common in the Arabuko- It is quite likely that there are still new honeyguides to be described 55 swallow’.