Western Cape Province, South Africa Mammals

Western Cape State of Biodiversity 2000 State of Biodiversity: Western Cape Province, South Africa Mammals Peter H. Lloyd Scientific Services Western Cape Nature Conservation Board Private Bag 5014 STELLENBOSCH 7599 Introduction (1986) which was most heavily relied upon. The result of this exercise was a list of all the mammals known to occur The Western Cape Province (W.C.P.) of South Africa, one within the southern African subregion (a region defined of nine provinces forming the country, is generally loosely as that south of a line joining the Kunene and regarded in South African terms as being “poor” with Zambesi Rivers), at currently recognized (warts and all!) respect to the number of its mammals when compared to subspecific level. For reference purposes typical the other eight provinces. This misconception has its subspecies (i.e. those subspecies whose trinomial is the origin in the fact that the Western Cape, essentially a same as the specific epithet; in other words where the winter rainfall region, lies adjacent to one of the richest species and subspecies names are the same) were included spots in the world in terms of mammalian diversity, even if that typical subspecies did not occur within the namely the summer rainfall region of the rest of South subregion. For the purposes of this paper, with minor Africa. In fact only when compared with the rest of our exceptions, only species are discussed. own country can the Western Cape be regarded as having The next step was to identify from W.C.N.C.B. records, a “poor” mammofauna in terms of biodiversity. However, some of the other Western Cape vertebrate and many of museum records and literature records of the current and the invertebrate groups do reflect higher levels of historic (recorded recent history) distribution of mammals, biodiversity, as do the plants; and almost all groups show those taxa known to occur or to have recently occurred in higher levels of endemism. The misconception regarding what is now politically defined as the Western Cape mammalian diversity in the Western Cape is partially Province. The precision of locality-recording exacerbated by the relatively low biomass mainly due to encompasses the full spectrum, from very coarse, to point the low nutrient status which is fairly characteristic of the localities determined to the nearest second in terms of fynbos biome. longitude and latitude. The historic distribution of the larger mammals within the The following step was to identify those taxa that were W.C.P. is probably better documented than that of any known to be restricted to this geographic region and those other faunal group in South Africa (see Skead, 1980; nearly restricted to it, in other words those taxa endemic or Skead, 1987; and Rookmaker, 1989) and the role that nearly endemic to the W.C.P. Because of the relatively mammals played in the development of nature unique character of the W.C.P. which encompasses the conservation in the W.C.P. is well summarized by Hey majority of the Cape Floristic Kingdom (C.F.K.), similar (1977). statistics for this region were also identified. Methods The subsequent step was to identify those mammalian taxa (both from our own records and the published literature) The relevant literature was consulted to assemble a list of which are considered to be at some level of risk in terms those mammalian species and other taxa that have been of continued survival, which has culminated in the recorded from within the present boundaries of the publication of local and international lists of threatened Western Cape Province, which are also known to live mammalian taxa (e.g. various IUCN Red Lists and various under relatively natural conditions, and to exclude those South African Red Data Books), and other categories for species/taxa which are only known to survive under purely purposes of protection, as has also been undertaken for captive conditions such as those prevailing in zoological other vertebrate and invertebrate groupings. These gardens and similar institutions or those maintained as pets threats/risks are well summarized in a variety of or for purposes of the pet trade. publications (see particularly Skinner, Fairall and Bothma, 1977; and Smithers, 1986), as are many of the critical Two of the most important references used were habitats. These are supplemented by W.C.N.C.B. records. “Classification of Southern African Mammals” (Meester, Rautenbach, Dippenaar and Baker, 1986) and “The Mammals of the Southern African Subregion (New Mammalogical Statistics Edition)” (Skinner and Smithers, 1990). The taxa listed in Of the approximately (due to taxonomic vagaries and these two references (with minor modifications to continuing developments in molecular genetic techniques) accommodate the latest available information, particularly 340 naturally-occurring species of mammal known from in the minor instances where these two references the southern African subregion, ±280 species are recorded differed) were entered into the biodiversity database, for South Africa (i.e. 82% of mammals occurring in the incorporating all the known species and subspecies Southern African Subregion are also to be found in South indicated. In the case of the latter it was Meester, et al. Africa) (Meester et al., 1986). For the W.C.P., the number 1 Western Cape State of Biodiversity 2000 of naturally-occurring mammalian species recorded is allowed to bring into the W.C.P. even more species which considerably lower at 160 (i.e. only 57% of the species never occurred here naturally. occurring in South Africa, also occur in the W.C.P.), hence the commonly heard statement that this province is Although not in quite the same proportion as the rest of impoverished with respect to mammals. South Africa, the Western Cape also has mammals which are endemic to its boundaries. Six mammal species (<4%) To place the mammalian riches of the Western Cape into are known to be endemic to both the C.F.K. and the proper perspective and context it is, therefore, instructive W.C.P. (see Table 1), but many more subspecies are also to compare the province to the whole of Western Europe, unique to these regions. A further two mammalian species which is roughly an order of magnitude larger. Both are known to be endemic to the C.F.K., and near-endemic Western Europe and the Western Cape, despite the to the W.C.P. (Chlorotalpa duthiae and Myomyscus difference in area, can claim to have been home to ±160 verreauxi), and a further four species are also known to be species of mammal in recent history. These range in size near-endemic to the province (Aethomys granti, from tiny shrews to the largest of whales in both regions. Chrysochloris asiatica, Myotis lesueuri, and Raphicerus However, whereas species of only nine of the 18 or 19 melanotis). A further 13 species endemic to the country as living mammalian Orders (depending on which references a whole also occur within the province, meaning that 25 of Table 1. Mammalian species which are endemic or near-endemic to the W.C.P. Species W.C.P. endemic C.F.K. endemic W.C.P. near-endemic Acomys subspinosus Ö Ö Bathyergus suillus Ö Ö Cryptochloris zyli Ö Ö Hippotragus leucophaeus Ö Ö Myosorex longicaudatus Ö Ö Tatera afra Ö Ö Chlorotalpa duthiae Ö Ö Myomyscus verreauxi Ö Ö Aethomys granti Ö Chrysochloris asiatica Ö Myotis lesueuri Ö Raphicerus melanotis Ö are used; e.g. Miller and Levine (1991) recognizing 18 the species endemic to South Africa are (or were) also and Orr (1966) recognizing 19) can be encountered in Western Cape species (as mentioned earlier at least one of Western Europe (Chinery, 1993), the Western Cape alone these species is now completely extinct). Of those has species from 13 or 14 of the 18 or 19 mammalian mammals that became extinct within the boundaries of the Orders (again depending on which references are used) province, but which survived elsewhere, only six have yet still surviving, and this in an area one tenth the size. to be re-established within the province in a truly wild state on formally conserved State land. These are Although a small number (probably only 11) of the represented by the lion (Panthera leo), the spotted hyaena species in the Western Cape became locally extinct, a (Crocuta crocuta), African wild dog (Lycaon pictus), the large proportion of these locally extinct species have now black rhinoceros (Diceros bicornis), the hippopotamus been re-established. Only one or two species, depending (Hippopotamus amphibius), and the Cape or African on which references are used, in the Western Cape have buffalo (Syncerus caffer). All of these species are under become completely extinct. These are the blue antelope, consideration for reintroduction to suitable areas provided Hippotragus leucophaeus, and the quagga, Equus quagga; funding for appropriate boundary fencing, or in some the latter, however, is considered by most modern cases reserve expansion, can be obtained, for those species taxonomists as the southernmost subspecies of the plains where this is necessary. Two of these species are widely zebra, Equus burchelli. Similarly the so-called "Cape expected to have occurred within the province but few or lion" is simply considered to represent the southernmost no material records currently appear to exist; these are the ecotype of the lion, Panthera leo. African wild dog and the spotted hyaena. Evidence to To these 160 species in the Western Cape, can probably be corroborate their existence or previous occurrence within added a further 15 or more species which are not native to the province is regarded as a natural history research the Western Cape (including species both alien to the priority.

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