Distribution and Protection of Endemic Or Threatened Rodents, Lagomorphs and Macrosceledids in South Africa
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S. Afe. J. Zool. 1995. 30(3) 115 Distribution and protection of endemic or threatened rodents, lagomorphs and macrosceledids in South Africa D.N. Mugo and A.T. Lombard' Percy FitzPatrick Institute of African Ornithology, University of Cape Town. Private Bag Rondebosch, 7700 Republic of South Africa G.N. Bronner Department of Mammals, Transvaal Museum, P.O. Box 413, Pretoria, 0001 Republic of South Africa C,M. Gelderblom and GA Benn Percy FitzPatrick Institute Receil'ed J(; February 1995: aCn'l'tcd 4 May /9Q5 Distribution patterns and protection status of endemic or threatened Lagomorpha. Macroscelidea, and Rodentia were analysed using museum point locality data and a geographic information system (GIS). The study area comprised the greater South Africa (including Lesotho and Swaziland). Species richness of the target species is highest in the south-western parts of the country, and hotspots of endemism cOincide with those of species rich ness. However, Red Data Book species hotspots are confined to the north-eastern parts of the country. One species richness hotspot in the Succulent Karoo contains no existing reserves, whereas all Red Data Book spe cies hotspots are protected. In general, all target species are well protected within existing reserves, but those found in the Succulent and Nama-Karoo, especially the Namaqua dune molerat (Bathyergus janetta) , the river ine rabbit (Buno/agus monticu/aris), Brants' whistling rat (Parotomys brantsit) , and the pygmy rock mouse (Petro myscus collinus) , are threatened by a paucity of reserves in these biomes. A heuristic reserve selection algorithm was used to identify a more representative reserve system for the protection of all target species. Ten representative reserves were identified, six of which already contain existing reserves. An analysis of biome specificity of all species revealed that Myomyscus verreauxii is endemic to the fynbos, Bathyergus janetta to the Succulent Karoo, Ze/otomys woosnami to the arid savanna, and Steatomys parvus to the savanna woodlands. No species are endemic to the Nama-Karoo or grasslands, although several species do show strong prefer ences for these habitats. It is recommended that hotspots. representative reserves, and species that are cur rently not protected, be awarded more protection. and that existing reserves which coincide with hotspots and representative reserves be managed for their mammal fauna. It is also recommended that the Red Data Book . status of four species, and six subspecies, should be changed. ) 9 0 0 Verspreidingspatrone en beskermingstatu5 van endemiese of bedreigde Lagomorpha, Macroscelidea, en 2 Rodentia is geanaliseer met behulp van museumpunt-liggingsdata en 'n geografiese informasiesisteem (GIS). d e Die studiegebied het die groter Suid-Afrika (insluitend Lesotho en Swaziland) ingeslui!. Die spesierykheid van t a teikenspesies was die hoogste in die suidwestelike gedeeltes van die land. Die brandpunte van endemisme het d ( met die van spesierykheid oorvleuel. Die brandpunte van Rooi Data-boekspesies is egter beperk tot die noord r oostelike gedeeltes van die land. Een spesierykheidbrandpunt, in die Sukkulente Karoo, bevat geen bewarings e h gebiede nie, terwyl al die brandpunte vir Rooi Data-boekspesies bewaar word. In die algemeen word aile teiken s i l spesies goed beskerm in bewaringsgebiede, maar die wat in die Sukkulente en Nama-Karoo aangetref word, in b besonder die Namakwa-duinmol (Bathyergus janetta), die oewerkonyn (Buno/agus monticu/aris), Brants se fluit u P rot (Parotomys brantsil), en die dwergklipmuis (Petromyscus collin us) word deur 'n gebrek aan bewaarde e gebiede in hierdie biome bedreig. 'n Proefondervindelike seleksieprosedure vir bewaringsgebiede is gebruik om h t 'n meer verteenwoordigende bewaringsgebiedsisteem vir die beskerming van al die teikenspesies te identifi· y b seer. Tien verteenwoordigende bewaringsgebiede is ge'identifiseer, waarvan ses reeds bestaande bewarings· d gebiede inslui!. 'n Ontleding van die bioomspesifisiteit van al die spesies het aangetoon dat Myomyscus e t verreauxii endemies is aan die fynbos, Bathyergus janetta aan die Sukkulente Karoo, Ze/otomys woosnaml aan n die dorre savanna en Steatomys parvus aan die savannabosland. Geen spesie is endemies aan die Nama· a r Karoa of die grasland nie, alhoewel verskeie spesies sterk voorkeur verleen aan hierdie habitats. Daar word g e aanbeveel dat aan brandpunte, verteenwoordigende bewaringsgebiede. en spesies wat op die oomblik c onbeskermd is, groter beskerming toegeken word. en dat bestaande bewaringsgebiede wat met brandpunte en n e verteenwoordigende bewaringsgebiede saamval vir hulle soogdierlauna bestuur word. Daar word oak aan· c i l beveel dat die Rooi Data·boekstatus van vier spesies en ses subspesies, verander moet word. r e d *To whom correspondence should be addressed n u y a w The present system of puhlicly owned protected areas (= groups; and the protection of historical uses (such as hunting). e t to In South Africa, existing reserves are heavi1y hiased towards a reserves) in South Africa is not the result of a national plan G conserve all aspects of biodiversity, but of historical ad hoc areas with large mammal faunas, mainly because of their t e IlOc n decisions (Siegfried 1989). Pressey (1994) lists the reasons tourism and hunting appeal. The ad designation of i b for ad hoc designation of reserves as: the relative lack of reserves has two main disadvantages. First. it tends to exclude a S value of selected sites for profitable exploitation by humans; certain species, communities or ecosystems (Pressey 1994). y b impressive scenery; recreation potential; influence of lobby Second, it makes the establishment of representative reserves d e c u d o r p e R 116 S. Afr. Tydskr. Dierk. 1995, 30(3) more expensive, thus reducing the likelihood of their cstab~ cies is listed as endangered (Bunolagus monticularis), two are Iishment (Pressey & Tully 1994). vulnerable, five are rare, six are indeterminate, and II are not It is often assumed that reserves designated to protect large listed (see Table I). mammal faunas will also provide adequate protection for With 29 families, 443 genera, and about 2021 species (Wil small mammals and other faunas. However, the validity of son & Reeder 1993), rodents form the largest mammalian this assumption has not been adequately tested. Gclderblom order. However, many questions regarding their taxonomy (1993) used range maps to test the effectiveness of the Current still remain unanswered (De Graaff 1981). Rodents are found reserve system in protecting small endemic mammal taxa in in most types of habitat owing to their wide-ranging adapta South Africa. She concluded that the existing reserve system tions. They occur in all zoogeographic regions except the does not adequately protect all the small mammals, and that Antarctic and some oceanic islands (De Graaff 1981). The this may have contributed towards the high proportion of order Macroscelidea comprises the elephant shrews, with four threatened species within this group. Tn addition, Siegfried & genera represented by 15 living species distributed in Brown (1992) used a reserve selection algorithm to assess the Morocco, Algeria, and Africa south of the Sahara (Wilson & effectiveness of the current reserve system in conserving bio Reeder 1993). They arc partly diurnal, and inhabit open diversity. They found that the existing arrangement of plains, savannas, brushlands, or forests. The order Lagomor reserves, particularly in the north-eastern and eastern parts of pha includes rabbits (Leporidae) and pikas (Ochotonidae) and the country, corresponds closely to an ideal configuration that comprises 13 genera, represented by 80 species (Wilson & would maximize the protection of resident, breeding, terres Reeder 1993). They have a world-wide distribution, and trial mammalian species. However, they also showed that it occupy terrestrial habitats from the Arctic to the tropics. does not adequately protect endemic mammal species. Another way to assess the effectiveness of current reserves Methods in protecting small mammals is to perform a gap analysis Species distribution data (Scott, Davis, Csuti, Noss, Butterfield, Groves, Anderson, Digital data were received from the following Museum col Caicco, D'Erchia, Edwards, Ulliman & Wright 1993; Lom lections: South African Museum, Transvaal Museum, Durban bard, August & Siegfried 1992). In this study, gap analysis is Natural Science Museum, Natal Museum, and the National used in a restricted sense to refer only to the taxa under inves Museum in Bloemfontein. Analogue data were obtained from tigation. We used a geographic information system (GIS) to the Carnegie Museum of Natural History and the Smithsonian identify hotspots, i.e. centres of total, endemic, or Red Data Institution in the USA. All data from museums were supplied Book (RDB, Smithers 1986) species richness. These hotspots in digital format at a quarter-degree square scale (QDS = 15' x arc then compared with the existing reserve system. Priority 15'). QDS codes were those defined by the government . ) areas for conservation outside of the existing system are iden 9 printer for 1:50 000 maps (e.g. 33 I 9AC). Once all data had 0 tified, and suggestions arc made as to how the present system 0 been collated, they were screened for errors. Particular atten 2 may be improved upon to include taxa at risk. Hotspots, how tion was paid to locality errors and possible mis-identification d ever, do not usually represent