A semi-quantitative inventory of spider diversity was done in the Blouberg Nature Reserve (BNR) and Western Soutpansberg Conservancy (WSC) situated in the Savanna Biome of the Limpopo Province, South Africa. Two hundred and ninety-six samples of one person-hour work each, comprised of five methods (vegetation beating, sweep netting, aerial hand collecting, ground hand collecting and leaf litter sifting) were divided between four relatively homogenous sites (plant communities) within a vegetation type of the BNR and WSC, respectively, an average of 37 per site. In addition, 25 pitfall traps were left open for a total of 20 days in each of the eight plant communities, 200 in total. We collected 1328 adult spiders representing 186 species of which 31% were singletons in the BNR vegetation type and 909 spiders in 222 species of which 41% were singletons in the WSC vegetation type. The number of species present was estimated using six estimators. The estimates varied between 233 and 307 for the BNR and 302 and 386 for the WSC. Inventory completeness was more than 70%. However, the fit to a lognormal distribution suggests that there are 370 species (750 000 individuals) and 445 (850 000 individuals) species in the universes (16 ha) sampled within the two vegetation types. Collector experience had no effect on the results of the inventory, whereas time of day had a very small yet significant effect. Seasonality only affected abundance and richness, but not assemblage composition. Sampling methods used had the biggest effect on our results. These results are used to design an optimized sampling protocol for standardized inventories in the Savanna Biome. Key words inventory completeness, SANSA, species richness estimates, checklist, Araneae, Arachnida, Savanna Biome. INTRODUCTIONSpecies richness and relative abundance of species in communities provide the basis for decisionmaking in conservation planning (Magurran 2004). Invertebrates are often neglected in conservation planning because of a lack of taxonomic and distributional data. Cardoso (2009) identified two factors that prevent the inclusion of invertebrates in conservation programmes, namely (1) comparability of results through standardization and (2) efficiency through optimized inventories. Coddington et al. (1991) proposed a sampling protocol for the rapid assessment of invertebrate diversity that can be structured to provide relative abundances of species at sites and enables comparisons between assemblages in disparate regions (Toti et al. 2000). This is a protocol where a sample is defined by one-person hour worth of effort in sampling spiders, employing an array of methods chosen to target different compartments of assemblages. A number of studies have adapted and applied this protocol for the temperate (Coddington et al. 1996;Scharff et al. 2003), tropical (Sørensen et al. 2002Coscaron et al. 2009) and Mediterranean (Cardoso et al. 2008a,b; regions of the world.Recent surveys of the spider fauna in the Western Soutpansberg have highlighted the contributi...

Little is known about the levels of stress experienced by African buffalos affected by injury, disease, or socio-ecological and anthropogenic factors. To be able to start filling this gap, we examined the suitability of two 11-oxoaetiocholanolone enzyme-immunoassays (EIAs) detecting 11,17 dioxoandrostanes (11,17-DOA) as well as faecal glucocorticoid metabolites (FGMs) with a 5b-3a-ol-11-one structure (3a,11oxo-CM), respectively, for monitoring stress-related physiological responses in African buffalo. An adrenocorticotrophic hormone (ACTH) challenge in one male and one female housed at Mokopane Biodiversity Conservation Centre, South Africa, showed a threefold increase in circulating cortisol levels in a sample taken 40 min post-injection. Corresponding 11,17-DOA levels increased tenfold (female) and 15-fold (male) above baseline, and 3a,11oxo-CM concentrations increased ninefold (female) and 12-fold (male) above pre-injection levels, indicating that both EIAs are suitable for measuring FGMs in African buffalo.In addition, 11,17-DOA levels monitored during the adaptation process of individual housing revealed an up to 14-fold elevation in FGMs. Storage of faeces at ambient temperature for up to 16 h post-defecation resulted in an significant increase in 11,17-DOA levels 2 h after defecation. Finally, higher individual baseline 11,17-DOA concentrations were found in samples defecated overnight, indicating a possible diurnal effect in excretion of FGMs in African buffalo.

The inclusion of spiders in conservation planning initiatives is confounded by several factors. Surrogates could facilitate their incorporation. In this paper we investigate the performance of a number of surrogate measures, such as higher taxa (genus, family), cross-taxon surrogates that are subsets of the spider assemblages (certain spider families) or non-overlapping groups (woody vegetation and birds), and the use of morphospecies. Birds and woody vegetation were included because they often form the focus of conservation planning initiatives. We assessed the surrogate measures based on their predictive power for species richness and extent to which conservation planning that maximizes representation of the surrogate is effective in representing spider diversity. A measure for the latter is the Species Accumulation Index (SAI). Generic richness as a higher taxon surrogate and the combined richness of the families Thomisidae and Salticidae were the best estimators of total species richness. Based on the surrogacy efficiency criterion, genera and the family Salticidae had species accumulation indices (SAIs) that were significantly larger than 95% confidence intervals of a random curve, while woody vegetation and birds turned out to be poor surrogates for spider diversity. The use of morphospecies as estimators is cautiously supported (adjusted R 2 = 0.85, for species richness, SAI = 0.73). The surrogates identified here provide a viable alternative to whole assemblage analysis but should be used with caution. The use of genera is confounded by unstable taxonomy and the difficulty of identifying specimens up to genus level. Geographic location and varying sampling effort between surveys did not have an effect on the surrogate performance of the two spider families, viz. Salticidae and Thomisidae. The former family has seen a flood of recent systematic work, whereas the latter's taxonomy is fairly well developed. These two families comprise ca. 20% of spider species observed in the Savanna Biome of South Africa and could provide a viable handle on spider diversity in this region.

Little is known about the levels of stress experienced by African buffalos affected by injury, disease, or socio-ecological and anthropogenic factors. To be able to start filling this gap, we examined the suitability of two 11-oxoaetiocholanolone enzyme-immunoassays (EIAs) detecting 11,17 dioxoandrostanes (11,17-DOA) as well as faecal glucocorticoid metabolites (FGMs) with a 5b-3a-ol-11-one structure (3a,11oxo-CM), respectively, for monitoring stress-related physiological responses in African buffalo. An adrenocorticotrophic hormone (ACTH) challenge in one male and one female housed at Mokopane Biodiversity Conservation Centre, South Africa, showed a threefold increase in circulating cortisol levels in a sample taken 40 min post-injection. Corresponding 11,17-DOA levels increased tenfold (female) and 15-fold (male) above baseline, and 3a,11oxo-CM concentrations increased ninefold (female) and 12-fold (male) above pre-injection levels, indicating that both EIAs are suitable for measuring FGMs in African buffalo.In addition, 11,17-DOA levels monitored during the adaptation process of individual housing revealed an up to 14-fold elevation in FGMs. Storage of faeces at ambient temperature for up to 16 h post-defecation resulted in an significant increase in 11,17-DOA levels 2 h after defecation. Finally, higher individual baseline 11,17-DOA concentrations were found in samples defecated overnight, indicating a possible diurnal effect in excretion of FGMs in African buffalo.

There is an established link between deforestation and negative hydrological effects which may affect watersheds. The number of the cycads Encephalartos transvenosus Stapf & Burtt Davy in South Africa is drastically reducing, and they are nearly extinct. Additionally, poaching and reduction in the population of cycads in reserves may impact negatively on watersheds in protected and buffer areas since the regeneration of this plant occurs over a long period. This research aimed to study the distributions of poached cycads, evaluate the factors responsible for poaching activity and suggest possible solutions towards conservation of E. transvenosus Stapf & Burtt Davy in some of the nature reserves in Limpopo province. Field observation was used to ascertain and collect locations of poached cycads. Data was obtained through the use of a questionnaire. Questionnaires were administered to rangers for the collection of data on causes of poaching, parts poached, measures taken and challenges of rangers in the nature reserves. Processing of the collected data was done by simple statistical analysis. The total population of rangers available in the reserves was used for the determination of the sample size of rangers by Slovin’s formula. Unemployment (46%) is the leading cause for poaching in Mphaphuli Nature Reserve, while trade is a leading factor in Modjadji and Lekgalameetse (37% and 60%) respectively. Debarked cycads amount to 14 (54%) while 12 of the total (26 poached cycads) were completely removed (46%). The most effective way of stopping the poaching of cycads as perceived by the rangers is by patrolling the nature reserves. The observed poaching of Encephalartos transvenosus is alarming since this plant has a low population size which is currently confined to the Limpopo Province in South Africa only. If poaching continues in the nature reserves, all cycads have the tendency of being removed. Therefore, there is a need to continually develop strategies for the conservation of cycads. The peculiar nature and challenges of each reserve have been established and unique solutions for these nature reserves in Limpopo Province have been proposed. Better conservation of cycad species can positively impact the hydrological process of the concerned area and better help the watersheds.

Human use of powerline servitude corridors for the secure transmission and distribution of electricity disturbs natural landscapes and changes vegetation patterns. We examined vegetation communities under two powerlines in the Limpopo province, South Africa (Khakhu line 22KV and Fundudzi 132KV powerlines). Twelve invasive alien species were identified in Khakhu and Fundudzi, dominated by Khaki bush Tagetes minuta, common guava Psidium guajava, black-jack Bidens pilosa, fierce thorn apple Datura ferox and common lantana Lantana camara. Sites closest to human settlements showed high alien species richness, whilst sites located further away were dominated by alien L. camara, but had a low overall species richness. Conversely, areas away from human settlements showed lower levels of alien invasion. Weak overlaps in the principal coordinates analysis polygons for the two powerline servitudes suggest that alien plant compositions are dissimilar, with five identified species groups being identifiable among sites, and thus a high potential for invasion success from multiple taxa. The research findings showed that powerline corridors could potentially trigger invasion success via disturbance as they act as pathways for arrival and should be a focus for management efforts to prevent further spread.

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