PhD (Zoology) / Department of Zoology / Invertebrate diversity is often neglected in conservation planning initiatives. There are also very few large-scale diversity studies in Africa, with most studies being restricted to single properties and spatial extents that are on average not much larger than 30 km2. Here, we provide a comparative regional assessment, two orders of magnitude larger than usual (30 000 km2), of epigeal spider, beetle and millipede diversity in the Vhembe Biosphere Reserve – the largest biosphere reserve in South Africa, and one of the largest in Africa. Firstly we aim to provide an evaluation of the ability of a range of broad and fine scale predictors to explain the variation in the diversity of these taxa. Secondly, we measured cross-taxon congruence between our selected invertebrate taxa and woody vegetation, and within-taxon surrogate efficiency. Thirdly we evaluated performance of existing and proposed zonations in representing regional invertebrate species diversity. Finally, to aid in the development of species conservation profiles for lesser known taxa, annotated check lists are provided for two neglected but dominant epigeal beetle families, Tenebrionidae and Carabidae. Vegetation units explained the largest and most significant component of beetle and spider diversity (richness and complementarity of alpha and beta diversity). Elevation and mean annual temperature played a lesser but still significant role. Overall, woody vegetation was a poor surrogate, especially for millipedes which have several localized endemics. The use of higher taxa (genus and tribe in particular) shows the greatest potential for conservation planning. The current zonation of the Vhembe Biosphere Reserve performed significantly better than expected in representing invertebrate diversity across the region. The reality though is that conservation decision-making is largely informed by knowledge on the distribution of rare, localized or endangered species, for which detailed species inventories are 10 required. Though a coarse filter approach is recommended, the augmentation of species level data provides an extra filter, and contributes to our knowledge of what taxa are in urgent need of protection. Targeting rare and endangered species in transition zones and developing conservation assessments and plans for these in relatively small areas would compliment existing conservation initiatives in the VBR. Annotated check lists ofTenebrionidae of the Vhembe Biosphere suggest that the family is particularly speciose, the assemblage being comprised of an east African and a Kalahari element which contributes significantly to local endemicity, and yielded three new species, one of which is described in the revision to the genus Anaxius, a group largely restricted to the mountainous areas of Limpopo Province. Carabidae were also found to be speciose, with the assemblage comprised of a large proportion of stenotypic species. There is support for the use of vegetation types in conservation plans but these should be augmented with species level conservation initiatives that target particularly transition and buffer zones. / NRF

Thesis (MScConsEcol (Conservation Ecology and Entomology))--Stellenbosch University, 2008. / The great pressures on freshwaters require their conservationists and managers to develop methods to rapidly and accurately assess their condition. Dragonflies are excellent indicators of habitat integrity and are effective organisms for this purpose. However, assessment must be done at the correct spatial scale. My aim here is to optimize the spatial resolution at which species are mapped, using three different concepts and methods in freshwater invertebrate distribution mapping, with special emphasis on IUCN Red Listing. The first is the extent of occurrence (EOO) concept, using the minimum convex polygon, and the second, the area of occupancy (AOO) concept, using IUCN and quaternary catchments. The third approach uses a river layer to compare the suitability of grids as opposed to catchments in mapping. In this study I found that area estimation based on minimum convex polygons should not be encouraged for aquatic organisms. This study also suggests that the IUCN concept of area of occupancy (AOO) should be redefined simply as occurrence, referring to known point-locality presences only and, if future data allow, to known absences. The IUCN extent of occurrence (EOO), for aquatic species, should be defined as ‘the sum of the smallest hydrological units identified of presently known, inferred or projected occurrences of a taxon, excluding cases of vagrancy, that are used to estimate the threat to a taxon’. A single hydrological unit is also the conservation or management unit. Currently, that unit is the quaternary catchment. Dragonflies have excellent potential as indicators of habitat integrity. For this purpose, my aim was to develop the Dragonfly Biotic Index (DBI) for South Africa and compare the DBI to another index, the Average Taxonomic Distinctness Index (AvTD), which was believed to have potential in assessments. The DBI and AvTD are correlated, which suggests that they could be used on a complementary basis to prioritize sites. The DBI is a low-cost, easy-to-use method and is already used for measuring habitat recovery. It has great potential for environmental assessment and monitoring freshwater biodiversity, especially as a complement to freshwater quality assessments that use macroinvertebrate scores. I thus recommend its integration into freshwater management and conservation schemes.

Thesis (MSc)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: The River Health Programme (RHP) is an assessment tool for monitoring the ecological state of rivers to ensure that they remain fit for use by present and future generations. This study, forming part of a RHP assessment conducted on the south-western Cape Hout Bay, Lourens and Palmiet Rivers, has the aim to (1) zone the rivers for representative site selection, (2) assess their habitat integrity (HI), (3) determine the influence of land use on riverine HI and (4) assess the river water quality at the time of the RHP assessments. (1) The desktop geomorphological zonation method used in RHP assessments has not been sufficiently previously tested on short rivers draining the Western Cape Mountains. The Lowland River Zone of the rivers studied, as well as the Hout Bay River’s Upper Foothill Zone, were found to have steeper gradients than expected, probably due to these rivers being shorter and consequently steeper than any on which the method was previously tested. The notion of one gradient river classification system being applicable throughout South Africa, with its diverse geology and climate, is unlikely. Rather a classification system modified for various physiographic features regions or by a factor based on river length is more realistic. (2) Although there is a general longitudinal decrease in HI downstream along the Hout Bay and Lourens Rivers, coinciding with increased anthropogenic activities, HI improves in the Palmiet River’s lower reaches through the Kogelberg Nature Reserve. Surrounding land use thus seems to be a major determinant of HI. Although the Index of Habitat Integrity (IHI) used appears to achieve its aim, it was found to be subjective. Categorisation of the IHI scoring is suggested. (3) The amount of natural versus disturbed land use occurring upstream of a site at a regional and local scale, is a good predictor of riverine HI. Regional alien forestry and local urbanisation have significantly strong negative effects on instream (r2 = -0.80, r2 = 0.80, p<0.05) and riparian (r2 = -0.81, r2 = -0.83, p<0.05) HI. Different land use types therefore appear to affect riverine HI at differing scales and thus managers must not only think on a local but also a catchment scale. (4) In the Hout Bay River, a filtering system (e.g. wetland) appears to improve the water quality between the middle and lower reaches. Along the Lourens River, high total dissolved salts, conductivity and inorganic nitrogen concentrations in the middle reaches are cause for concern. Along the Palmiet River there appeared to be insufficient oxygen to support most aquatic life forms at Grabouw. Impoundments in the middle reaches act as sinks for nutrients and salts, but the Huis and Krom tributaries downstream then appear to degrade the water quality of the Palmiet River’s lower reaches within the Kogelberg Nature Reserve. Together with the results of simultaneous biotic assessments, these results should be used to develop management actions to improve the ecological health of these rivers. The results have been used in a State-of-Rivers Report for the south-western Cape. / AFRIKAANSE OPSOMMING: Die Riviergesondheidsprogram (RGP) is 'n asseseringsinstrument wat die ekologiese stand van riviere monitor om te verseker dat hulle steeds bruikbaar bly vir huidige en toekomstige geslagte. Hierdie studie maak deel uit van 'n RGP-assessering van die Lourens-, Houtbaai- en Palmietrivier in die Suidwes-Kaap en het ten doel om (1) die riviere te soneer vir verteenwoordigende terreinseleksie, (2) die habitat-integriteit (HI) te assesseer, (3) die invloed van grondgebruik op rivier-HI te bepaal en (4) die kwaliteit van rivierwater tydens die RGP-assesserings te bepaal. (1) Die geomorfologiese-soneringsmetode wat in RGP-assesserings gebruik word, is nog nie voorheen genoegsaam vir die kort riviere wat die Wes-Kaapse berge dreineer, getoets nie. Daar is bevind dat die studiegebied riviere in die laagland-sones skerper gradiënte het as verwag, gehad het. Dit kan moontlik toegeskryf word aan die riviere wat korter en dus steiler is as enige van dié wat voorheen met die metode getoets is. Die moontlikheid dat een gradiëntklassifikasiestelsel vir riviere regdeur Suid-Afrika met sy diverse geologie en klimaat toegepas kan word, is onwaarskynlik. 'n Klassifikasiestelsel aangepas vir verskillende fisiografiese streke of met 'n faktor gebaseer op rivierlengte, is meer realisties. (2) Alhoewel HI stroomaf langs die Lourens- en Houtbaairivier in die algemeen longitudinaal saam met die toename in antropogeniese aktiwiteite afneem, verbeter die Palmietrivier se HI waar dit laer af deur die Kogelbergnatuurreservaat vloei. Die gebruike van aanliggende grond blyk dus 'n belangrike bepaler van HI te wees. Die Indeks van Habitatintegriteit (IHI) bereik klaarblyklik die vereiste doel, maar is te subjektief. Kategorisering van die IHI-waardes word voorgestel. (3) 'n Goeie voorspeller van rivier-HI is die hoeveelheid natuurlike teenoor versteurde grondgebruik stroomop van 'n terrein op 'n streeks- en lokale skaal. Die sterk negatiewe effek van uitheemse plantegroei in die omgewing en lokale verstedeliking op stroom- (r² = -0.80, r² = 0.80, p<0.05 ) en oewer-HI (r² = -0.81, r² = -0.83, p<0.05) is beduidend. Verskille in tipe grondgebruik beïnvloed rivier-HI op verskillende vlakke; bestuurders moet dus plaaslik en aan die opvanggebied dink. (4) In die Houtbaairivier lyk dit asof 'n filtreringstelsel (bv. vleigrond) die waterkwaliteit tussen die middel- en lae gedeeltes verbeter. In die loop van die Lourensrivier is hoë totale opgeloste soute, geleidingsvermoë en anorganiese stikstofkonsentrasies in die middelgedeelte 'n rede tot kommer. In die Palmietrivier by Grabouw was die suurstof te min om die meeste akwatiese lewensvorme te onderhou. Opgedamde water in die middel gedeeltes dien as 'n sink vir voedingstowwe en soute, maar dit lyk asof die Huis- en Kromrivier die waterkwaliteit van die Palmietrivier stroomaf in die Kogelbergnatuurreservaat degradeer. Saam met die resultate van gelyktydige biotiese assesserings, kan hierdie resultate gebruik word vir die ontwikkeling van bestuursaksies om die ekologiese toestand van hierdie riviere te verbeter. Die resultate is gebruik in 'n toestand-van-riviere-verslag vir die Suidwes-Kaap.

Thesis (MTech (Nature Conservation))--Cape Peninsula University of Technology, 2015. / The klipspringer (Oreotragus oreotragus subsp. oreotragus) population became extinct on the Cape Peninsula in 1930. Being re-introduced into Table Mountain National Park (TMNP) in 1999 it became one of the species of special conservation concern to monitor in the Park. Most klipspringer territories are known by Park management but the distribution of all potentially suitable habitats for this species in the Park is not known. The main aim of this study is to produce a distribution range map that is representative of all potentially suitable habitats for the klipspringer within TMNP, through the use of a species distribution modelling tool. Since only presence data were available for this study, a popular presence-only modelling tool namely maximum entropy (MaxEnt) was used. The use of MaxEnt in species distribution modelling has become popular as it has proven to provide robust predictions of a species’ geographic distribution. Klipspringer occurrence data and five environmental variables namely altitude, slope, aspect, vegetation, and distance to urban edge were used as model input. Occurrence data were sourced through existing databases and employing a stratified random sampling technique of dividing the Park into different habitat subtypes to survey the Park for more klipspringer occurrences. These habitat subtypes consisted of a variety of vegetation communities or vegetation types and altitudinal and slope ranges available in the Park. Grid size for all the raster layers used was 10x10 m. Spatial filtering of one point per 100 m² grid was used to eliminate clumping of points. Six models were run at different regularisation multiplier (RM) values namely 0.25, 0.5, default (1), 2, 4 and 7. To assist in better understanding of the spatial extent of the occurrence data and the areas inhabited by the klipspringer, home range analyses were carried out. This was done through kernel density estimation in the Geospatial Modelling Environment (GME). All six bandwidth parameters in GME namely smoothed cross validation (SCV), biased cross-validation (BCV), a second BCV algorithm, plug-in estimator, least squares cross validation and the likelihood cross validation (CVh) were tested. The smoothed cross validation and likelihood cross validation bandwidth algorithms provided the best visual output of klipspringer home ranges and territories. Home range sizes from the SCV output ranged from about 3 – 11 ha across the study area, and home range size for the CVh output ranged from 0.6 – 2.5 ha. The output from the CVh algorithm was interpreted as territories rather than home ranges, as it is based on a univariate kernel unlike, the SCV algorithm that produces rotated bivariate kernels. iv The default regularisation multiplier of 1 provided the best probability distribution output, whilst values lower than the default tended to underestimate the prediction and those values higher than the default were tending towards overestimations. Response curves for the default RM also gave the most ecologically meaningful responses of the klipspringer to each environmental variable. Model evaluation in the form of area under the receiver operating characteristic curve (ROC AUC) showed that all models performed well. Therefore, the choice of the “best” model was based on the ability to provide ecological interpretation, on the shape of the response curve and the probability distribution maps. Consequently, the default RM model was considered the best, with an AUC score of 0.903. Altitude and vegetation contributed the most to suitable habitat and therefore indicates that klipspringer in the Park do prefer high altitudinal areas with the right vegetation to feed on. Suitable altitudinal ranges are from 400 m.a.s.l. and higher and ericaceous fynbos is the most preferred vegetation community. Slope, aspect and distance to urban edge played a less important role in suitable klipspringer habitat. The probability map and an additional binary map produced at the 10 percentile training logistic presence threshold showed that suitable habitat for the klipspringer occurs in all three sections of the Park in different proportions. These maps can be used by Park management to prioritise conservation efforts and future re-introductions. / National Research Foundation

MESHWR / Department of Hydrology and Water Resources / See the attached abstract below