A dung beetle survey of selected Gauteng nature reserves: implications for conservation of the provincial scarabaeine fauna

Aquantitativedungbeetlesurvey(Coleoptera:Scarabaeidae:Scarabaeinae)wasconducted insixGautengnaturereserves(Tswaing,Leeuwfontein,Roodeplaat,Ezemvelo,AbeBailey, Suikerbosrand) representativeof theprovincial rangeinenvironmental conditions. The studyprovidedaprovincial species inventorythat has beentestedfor completeness bycomparisonwithmuseumreferencematerial. It alsopermittedananalysisof major influencesonregional(altitude,annualrainfall)andlocal(soilandvegetationtype)patterns of speciesabundance. Thesurveyrecordedatotal of 152species. Althoughafurther29 specieswererepresentedinreferencecollections,theirabsencefromthepresentworkwas probablyduetohabitat,food,ortemporalspecializations.Multivariateanalyses(clustering, MDS)ofspeciesabundancedataformedsixclusters,eachcomprisingexclusivelythesitesin singlereserves. Thisindicatesthatregionalbetween-reservefaunaldifferencesaregreater thanlocal withinreservedifferences, thusdemonstratingthevalueof eachreserve. Ina hierarchical analysisofobliquefactors, fiveoutofsevenstatisticallydefinedclusterscom- prisedexclusivelythesitesinsinglereserveswithSuikerbosrandsplitintwo.Theseclusters werevariouslycorrelatedwithnineextendedfactors.Alongsevenfactors,correlationswere uniqueoressentiallyuniquetosinglereservesandwerefairlyhigh,particularlyatinterme- diatealtitude. Alongtheremainingtwosharedfactors, therewereopposingtrendsinthat correlationseitherdecreasedwithhigheraltitudeordecreasedwithloweraltitude. Thus, eachclustershowsthreecoefficientsofdetermination, onerepresentingtheproportionof varianceduetosharedhighlandfaunalinfluence,onerepresentingthatduetosharedlow- landfaunal influenceandthethirdrepresentingthatduetouniquelocal faunal composi- tion. Theanalysesidentifythetransitionfromlowlandtohighland-dominatedfaunas, the relativefaunal distinctivenessofeachreserve, andomissionsfromtheprovincial reserve system.