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Summary 1.Although it is widely assumed that protected areas conserve species that would not survive elsewhere, this assumption is seldom tested. The aim of the study was to determine the respective roles of a nature reserve and commercial and subsistence rangeland in preserving terrestrial arthropods and reptiles in xeric succulent thicket in the Eastern Cape, South Africa. 2. Faunal diversity on a nature reserve (the Great Fish River Reserve Complex) was compared with a historically overgrazed commercial farm, an intensively managed, conservatively stocked commercial farm and a communal grazing area. Terrestrial arthropods and reptiles were caught in paired pitfall traps inside and outside the nature reserve, specimens being sorted into recognizable taxonomic units (RTU). The taxa occurring in each land management unit were compared using RTU diversity, a hierarchical richness index (HRI), community similarity and uniqueness. 3. The nature reserve contained more RTU and a greater HRI than adjacent land for most arthropod groups, and also supported more unique taxa than the other study localities. 4. Snakes and lizards, in contrast, were almost twice as abundant in the communal grazing area as elsewhere, although reptile species diversity was similar at all localities. 5. Each individual locality contained fewer than 62% of the total number of arthropod RTU and 55% of the total reptile RTU; the communal grazing area contained only 37% of the total number of arthropod RTU collected in the study area. 6. Nineteen (73%) of the ant, 18 (69%) of the weevil, 60 (70%) of the spider and 12 (60%) of the grasshopper RTU and 10 (66%) of the reptiles were shared by the three land uses. Six new weevil species and probably several new arachnid species were collected, but all the new weevils were confined to the nature reserve. 7. The communal grazing area differed most from the nature reserve in richness and community composition, followed by the conservatively stocked commercial farm. The historically overgrazed commercial farm was most similar to the nature reserve. 8. The communal grazing area was characterized by xeric-adapted reptiles and predatory arthropods whose ranges are centred in the semi-arid parts of South Africa. In contrast, the nature reserve and commercial farms supported more mesic-adapted reptiles and herbivorous arthropods. 9. Synthesis and applications. The data show how protected areas are key to conserving those species that decrease under heavily grazed and disturbed conditions. However, they also illustrate that diverse land-use mosaics promote gamma diversity in the xeric succulent thicket of South Africa. Conservation policies that include protected space in the wider environment and conserve habitat diversity are likely to both promote regional richness and support scarce species.

Seabird guano is recognized as a powerful fertilizer and its entry into the intertidal zone of seabird breeding islands off the west coast of South Africa is hypothesized to cause enhanced intertidal algal production. Intertidal nutrient levels and algal production were measured monthly on the shores of seabird islands and on nearby mainland shores where no aggregabons of seabirds occur. The shores of seabird islands were characterized by significantly higher levels of nutrients and significantly enhanced algal production. Nutrient enrichment, in conjunction with the predatory activity of African black oystercatchers on ~nterbdal herb~vorous hmpets, leads to the formation of extensive, permanent mats of foliose algae on the shores of seabird breeding islands. Mussel spat, polychaetes and small crustaceans settle in the algal mats and provide food for small shorebirds. The structures of intertidal algal, invertebrate and avlan communities on the shores of seabird islands are significantly altered by the activities of guano-producing seabirds and predatory shorebirds.

Egyptian geese (Alopochen aegyptiaca) occur in large numbers on golf courses in southwestern South Africa. They cause physical and financial damage to the courses and are a nuisance to golfers and golf course managers. Most control measures used to reduce the problem have been unsuccessful. We investigated the potential for environmental management options by determining which landscape features attract geese to certain areas within golf courses and cause them to avoid others. Goose vigilance levels were lower in use than in non-use areas regardless of group size (t 1 ¼ 5.837, P 0.001, F 1 ¼ 53.877, P 0.001). This behavior suggested that geese were attracted to some areas because they perceive them to be safer. Landscape features that attracted Egyptian geese were large open patches of lawn (>1.5 ha) and proximity to water bodies (<100 m). Water bodies should not be adjacent to open foraging or loafing areas. Other modifications may include planting herbaceous vertical vegetation around water bodies and open fairways to reduce habitat openness and predator visibility. Our results suggest that the level of the goose problem at any golf course is a consequence of the intrinsic properties of that course and not influenced by the extent of the problem at nearby golf courses. Ó 2014 The Wildlife Society.

Rates of algal production were measured at 6 rocky intertidal sites on the southwestern Cape coast, South Africa, where populations of the limpet Patella granularis occur. Rates of algal production and limpet mortality were recorded at each site and both factors affected limpet reproductive fitness. Limpet growth rates and biomass at different sites were significantly correlated with rates of algal production, and limpet mortality was related to the density of African Black Oystercatchers, important predators of P. granularis. Life-time gametic output of a hypothetical cohort of limpets at each site was modelled using the measurements of growth, reproduction and mortality made at each site. Limpet cohorts at sites with rapid rates of algal production were predicted to have a larger life-time production of gametic material than cohorts at sites with slow algal production rates, except in instances of acute predatory pressure. In the light of the overriding influence of food supply on the expression of limpet life-history parameters, it is imperative that researchers consider food availability before assuming that local, population-specific differences in life-history patterns are due to genetic differences.

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SummaryThe provision of artificial nests can improve the conservation status of threatened bird species that are limited by nest-site availability. The shortage of natural cavity nesting sites is one factor limiting the population growth of the Southern Ground Hornbill Bucorvus leadbeateri. In an 1,800 km2 study area in north-eastern South Africa, 31 wooden nest-boxes were installed during 2002–2015. We investigated the relationships between nests, as well as environmental and social factors, with breeding. Generalised linear mixed models were fitted to the observational data and identified positive relationships between breeding attempts and each of home range size and the previous year’s rainfall; as well as positive relationships between breeding success (amongst the groups that attempt breeding) and each of earlier breeding, nest height and thickness of the nest cavity wall. The provision of nest-boxes increased the number of breeding groups and although breeding success also increased initially, it later declined as the density of breeding groups increased above 20 groups. Although nest-boxes alone did not increase overall breeding success, they are an effective conservation tool to enhance the population of Southern Ground Hornbills if spaced optimally, to enhance reproductive output in areas where suitable nest-sites are scarce or lacking.