Raptor conservation in the Northern Cape Province,South Africa

Anderson, M.D. 2000. Raptor conservation in the Northern Cape Province, South Africa. Ostrich 71 (1 & 2): 25–32.

The semi-arid Northern Cape is the largest and most sparsely populated province in South Africa. One of the main economic activities is sheep farming, and the properties are generally very large (>5 000 ha). A heterogeneous environment results in many habitats for a wide diversity of raptors. Fifty-one different species have been recorded, of which 37 are resident, 21 are common, and eight species are listed in the South African Red Data Book—Birds. As habitat degradation is limited, besides the areas immediately adjacent to the perennial rivers, raptors are still commonly encountered in many areas. Conflict with small-stock farming, however, results in some birds being inadvertently or directly persecuted each year. Two farmer questionnaire postal surveys (1976 and 1992) indicated a decrease in range and abundance of certain scavenging species, such as the Tawny Eagle. The more recent survey also indicated that most stock mortalities occurred in the mountainous areas, with the Black Eagle being the apparent culprit. In the Northern Cape there are both positive and negative anthropogenic effects on raptors. For example, 14 species have been recorded breeding on man-made structures, while 18 species have been documented to drown in farm reservoirs. Through the activities of the Raptor Conservation Group, the Northern Cape Nature Conservation Service and the Northern Cape Raptor Conservation Forum various threats are being addressed. Raptor conservation activities include: monitoring of raptor breeding populations, road censuses, farmer extension, establishment of raptor conservancies, rehabilitation of injured raptors, issuing of certificates to land-owners who have breeding raptors on their properties, presentation of the annual Gariep Raptor Conservationist Award, production and distribution of raptor pamphlets and booklets, modification of farm reservoirs to prevent raptor drownings, modification of powerlines to prevent electrocutions, and establishment of “vulture restaurants”. Through these efforts, the status of many raptor species is improving and species such as the Bateleur and Lappet-faced Vulture are becoming increasingly common.     

An ethnobotanical survey of the Agter–Hantam, Northern Cape Province, South Africa

The use of a rapid appraisal methodology, followed by a new approach that we refer to as the Matrix Method, has revealed a wealth of traditional knowledge on useful plants amongst people of Khoi–San decent in the Agter–Hantam, Calvinia district, Northern Cape Province of South Africa. The data include 14 new species records of useful plants; 20 new vernacular names and 99 new uses for 46 of the plant species, showing that Khoi–San ethnobotany is still incompletely recorded and that there is an urgent need to document this wealth of traditional knowledge before it is lost forever. This article also introduces two new terms — the Ethnobotanical Knowledge Index (EKI), a quantitative measure of a person's knowledge of local plant use (value between 0 and 1), and the Species Popularity Index (SPI), a quantitative measure of the importance or popularity of each species (value between 0 and 1). In the Agter–Hantam, the EKI varied from 0.20 to 0.93 in older people but even young children had EKI values of 0.27. The best known and most popular indigenous useful plants in the Agter–Hantam are Aloe microstigma (a new species record, with a SPI of 0.97), Hoodia gordonii (SPI = 0.94), Microloma sagittatum (0.94), Sutherlandia frutescens (0.92), Quaqua incarnata (0.92) and Galenia africana (0.85). The new quantitative method will allow for direct comparisons of the preservation of traditional plant knowledge and the importance of various plants species in different communities.     

Seasonal abundance, reproduction and hunting of common quail Coturnix coturnix in the Eastern Cape Province, South Africa

This study investigated the potential overlap between breeding and hunting seasons for a population of common quail Coturnix coturnix in the Alexandria District. Seasonal abundance (assessed as the number of birds flushed per unit effort), sex ratios and reproductive condition (based on gonad sizes) of the quail were measured over a period of 16 months, including two hunting seasons. Hunting impacts were assessed in terms of the number of birds killed per unit of hunting effort. Quail exhibited a spring peak in abundance and reproduction, which coincided with the legal hunting season, and bird numbers varied markedly between years. Sex ratio varied, with males dominating early in spring. Hunters killed nearly 60% of the birds flushed, and hunter efficiency was positively correlated with the abundance of quail. These results confirm the dilemma for managers, as quail are currently hunted during the main breeding season and offtakes are high. The development of management strategies is hampered by a lack of understanding of the population biology and ecology, and impacts of hunting. A number of possible hunting strategies are discussed. Since current harvests may not be sustainable, further research is necessary.     

Age-related differences in abundance and habitat occupation of Steppe Buzzards,Buteo buteo vulpinus,in the Western Cape Province,South Africa

Linear densities of Steppe Buzzards, Buteo buteo, were studied along roads at the southernmost edge of the nonbreeding range in the Western Cape Province, South Africa. Adults arrived before first-year birds; peak populations of the former occurred from December to February, and of the latter from January onwards. Except during periods with rapidly changing numbers during arrival and departure, the proportion of first-year birds in three different areas was negatively related to the density of adults. This may be the result of competitive exclusion by adults, or of age-related differences in habitat preference. Adults dominated first-year birds at hunting perches. First-year birds were most frequently found in more closed habitat, where they attempted to kleptoparasitize adults in 18% of all observed instances of prey mantling.     

Risk factors of porcine cysticercosis in the Eastern Cape Province, South Africa

There is a high prevalence of Taenia solium taeniosis/cysticercosis in humans and pigs in the Eastern Cape Province (ECP) of South Africa. The objective of this study was to identify risk factors of porcine cysticercosis in select districts of the ECP. Data were collected in 2003 by interviewing 217 pig producers from the area. Blood samples were collected from 261 of their pigs, which were tested using two enzyme-linked immunosorbent assays (ELISA) for the presence of antibodies to cysticercosis. Frequencies of both owner- and pig-level characteristics were determined. For pig-level analysis, all bivariable and multivariable associations were determined using the surveylogistic procedure of the SAS/STAT? software to accommodate for the intraclass correlation that exists for clusters of pigs within one owner and for clusters of owners within a district. All tests for significance were performed at the α?=?0.05 level, and adjusted odds ratios (aOR) and 95% confidence intervals (CI) were determined. Among the respondents, 48% of their households lacked a latrine, 98% slaughtered pigs at home, and 99% indicated that meat inspection services were not available. On bivariable analysis, there was a significant association between porcine infection and district (p?=?0.003), breed (p?=?0.041) and the absence of a latrine (p?=?0.006). On multivariable analysis, the absence of a latrine was the only variable significantly associated with porcine infection (aOR?=?1.89; 95% CI?=?1.07, 3.35) (p?=?0.028). The increased odds of porcine infection with households lacking a latrine contributes to our understanding of the transmission of this parasite in the ECP. Determining and addressing the risk factors for T. solium infection can potentially lower the very high prevalence in humans and pigs in this endemic area.     

Activity patterns of springhares from the Eastern Cape Province, South Africa

The activity patterns of springhares Pedetes capensis ( Rodentia: Pedetidae ) from the Eastern Cape Province, South Africa, were investigated by counting the number of springhares active above ground at regular intervals throughout the night at different times of the year and under different weather conditions and phases of the moon. A combination of time of year, time of night and level of illumination best explained springhare activity, accounting for 43% of the variation in springhare numbers. Springhare activity generally reached its peak soon after dark, thereafter remaining fairly constant throughout most of the night and only decreasing in the 2–4-h period before sunrise. On those nights when the moon either rose or set during the night, this pattern was modified by the level of illumination. Springhares responded to moonlight by reducing above-ground activity, shifting activity to dark, moonless periods of the night, and by reducing their use of open space. Except for extremes, other weather conditions had no significant effect on springhare activity.     

Duinefontein 2: an Acheulean site in the Western Cape Province of South Africa.

Excavations at Duinefontein (DFT) 2 near Cape Town, South Africa have recovered numerous stone artefacts and animal bones on an ancient surface sealed within iron-stained eolian sands. U-series analysis of an overlying calcrete places the sands before 150 ka ago, while the large mammal taxa imply an age between 400 and 200 ka ago. The artefacts include a classic Acheulean handaxe and probable biface shaping flakes that support this age estimate. The principal mammalian species are long-horned buffalo, black wildebeest, greater kudu, Cape zebra, and grysbok/steenbok, which imply a grass-and-bush mosaic instead of the historic small-leafed shrubland.Hippopotamus and reedbuck indicate that water stood nearby, probably in dune swales. The large mammal bones are mostly vertebrae and other axial elements, often in near-anatomical order. Both proximal and distal appendicular elements are rare. Bones with carnivore damage are common, but ones with stone tool marks are scarce. The sum suggests a water-edge attritional death site where people played a minimal role and carcasses were disarticulated mainly by carnivore feeding and by trampling. Stone tool marks tend to be equally rare at other Acheulean attritional death sites, and the implication may be that Acheulean people rarely obtained large mammals, whether by hunting or scavenging. Human scavengers at DFT2 would not have encountered a disproportionate number of distal (versus proximal) limb elements, and it follows that the tendency for distal elements to dominate many archeological assemblages need not reflect scavenging versus hunting. Even if DFT2 was not itself a locus of intense human activity, it provides a useful baseline for evaluating bone damage, skeletal part representation, and other variables at sites where people were deeply involved.     

The mammalian fauna associated with an archaic hominin skullcap and later Acheulean artifacts at Elandsfontein, Western Cape Province, South Africa

The Elandsfontein site, Western Cape Province, South Africa, is well known for an archaic hominin skullcap associated with later Acheulean artifacts. The site has also provided nearly 13,000 mammalian bones that can be identified to skeletal part and taxon. The assemblage derives from 49 species, 15 of which have no historic descendants. Comparisons to radiometrically dated faunas in eastern Africa indicate an age between 1 million and 600 thousand years ago. Unique features of the fauna, including the late occurrence of a dirk-toothed cat and a sivathere, may reflect its geographic origin in a region that was notable historically for its distinctive climate and high degree of biotic endemism. Together, taxonomic composition, geomorphic setting, and pollen extracted from coprolites indicate the proximity of a large marsh or pond, maintained by a higher water table. The small average size of the black-backed jackals implies relatively mild temperatures. The sum of the evidence places bone accumulation during one of the mid-Pleistocene interglacials that were longer and cooler than later ones, including the Holocene. The geomorphic context of the fauna presents no evidence for catastrophe, and most deaths probably resulted from attritional factors that disproportionately killed the young and old. However, only the dental-age profile of long-horned buffalo supports this directly. Field collection methods biased skeletal-part representation, but originally, it probably resembled the pattern in the younger, marsh-edge Acheulean occurrence at Duinefontein 2, 45 km to the south. Excavation there exposed multiple vertebral spreads, which probably mark carcasses from which hominins or large carnivores removed the meatier elements. Bone damage at both sites suggests that, despite abundant artifacts, hominins were much less important than carnivores in the bone accumulation. Together with limited observations from other sites, Elandsfontein and Duinefontein provisionally suggest that Acheulean-age hominins obtained few large mammals, whether by hunting or scavenging.     

The significance of chicory to the diet of common duiker at Grants valley, Eastern Cape Province, South Africa

South Africa is considered one of the top four chicory (Chichorium intybus) producing countries of the world and commercial growing of the plant in the country is restricted to a small area in three districts of the Eastern Cape Province. Faecal analysis technique was used to study the diet of common duiker (Sylvicapra grimmia Linnaeus, 1758) in a chicory growing region at Grants valley. One of the principal items in the diet of these antelopes was chicory and the crop provided more than one third (35.6%) of the winter diet and a substantial proportion (14.4%) of the spring diet of common duiker. These findings confirmed earlier reports of common duiker feeding on cultivated crops and may have profound implications for the South African chicory industry. The study also confirmed earlier findings that common duiker are selective feeders and predominantly browsers, consuming only a very small proportion of monocotyledonous plants.     

Mesozoic palaeogeography of the Southern Cape,South Africa

Four palaeogeographical reconstructions are presented for the southern Cape covering the period Late Permian to Late Cretaceous. This time spans the commencement to an advanced stage of breakup of Gondwanaland, during which the area moved from a mid-continental, high latitude, to an ocean-dominated, middle latitude position. These movements can be traced in facies changes and erosional cycles associated with the rift between West Gondwana and Antarctica (proto southwest Indian Ocean) and the later rift between South America and Africa (proto southeast Atlantic Ocean).     

Geographical affinities of the Cape flora, South Africa

Aim The flora characteristic of the Cape Floristic Region (CFR) is dominated by a relatively small number of clades that have been proposed as ‘Cape clades’. These clades have variously been suggested to have African or Austral affinities. Here we evaluate the support for these conflicting hypotheses. In addition, we test the hypothesis that these clades share a common time of differentiation from their geographical neighbours. Location The Cape Floristic Region, South Africa Methods We use both published and unpublished phylogenetic information to investigate the geographical sister areas of the Cape clades as well as the timing and the direction of biogeographical disjunctions. Results Almost half of the Cape clades for which unambiguous sister areas could be established show a trans‐Indian Ocean disjunction. The earliest trans‐Indian Ocean disjunction dates from 80 Ma. Other disjunctions date from various times in the Cenozoic, and we suggest that the process of recruiting lineages into the Cape flora might be ongoing. Relatively few Cape clades show a sister relationship with South America and tropical Africa, despite their relative geographical proximity. Numerous Cape clades contain species also found on tropical African mountains; in all cases tested, these species are shown to be embedded within the Cape clades. While many Cape clades show a relationship with the Eurasian temperate flora, this is complicated by their presence in tropical Africa. The single case study addressing this to date suggests that the Cape clade is nested within a European grade. Main conclusions Although many Cape clades show Austral rather than African relationships, there are numerous other patterns suggestive of a cosmopolitan flora. This spatial variation is echoed in the temporal data, from which, although there is wide variance around the dates of disjunctions, it is clear the Cape flora has been assembled over a long time period. There is no simple hypothesis that can account for the geographical sources of the currently distinctive Cape flora. The phylogenetic positions of Afromontane members of Cape clades suggest a history of dispersal from the CFR, rather than the reverse.     

Euseius addoensis addoensis,an effective predator of citrus thrips,Scirtothrips aurantii,in the eastern Cape Province of South Africa

The predacious mite,Euseius addoensis addoensis (McMurtry) (Acari: Phytoseiidae), significantly (P<0.05) reduced scarring on Palmer Navel oranges,Citrus sinensis (L.) Osbeck, caused by the citrus thrips,Scirtothrips aurantii Faure (Thysanoptera: Thripidae). A chemical exclusion method employing dicofol was used to determine the effect of the predator and numbers ofS. aurantii were monitored on sticky yellow traps. At two sites where numbers of citrus thrips and predacious mites were high, the percentage fruit culled from export quality due to damage byS. aurantii was reduced from 25.5 to 15.5% and from 32.7 to 18.7% by predacious mite activity.Euseius a. addoensis sometimes prevented damage from exceeding 1% cull and was most effective when mean numbers exceeded one mite per inside leaf at petal fall. The best correlation between numbers of mites and the percentage fruit culled at harvest was –0.96 at the location with the highest number of citrus thrips. Tartar emetic (0.398% a.i.) plus sugar (0.4% a.i.) treatments for citrus thrips were slightly detrimental toE. a. addoensis populations but their numbers soon recovered. An alternative treatment, methiocarb 0.016% a.i. plus sugar (0.4% a.i.), almost eliminated the predacious mites and resulted in more citrus thrips damage (10.7% cull) than in the adjacent untreated control (0.2% cull) which contained predacious mites.     

Habitat selection by the Cape clawless otter (Aonyx capensis) in rivers in the Western Cape Province, South Africa

We radio‐tracked seven Cape clawless otters (Aonyx capensis) (Schinz, 1821) in two rivers in the Western Cape Province, South Africa, providing data on their habitat selection. Habitat type was investigated at a scale that enabled us to separate the effects of types of riparian vegetation, geomorphology and anthropogenic influences. Otters selected areas with boulders and/or reed beds, which provided high crab density and shelter. Direct observations showed that they used two foraging modes depending on the habitat selected. Otters could select open water within c. 8 m of the shore, dive and surface with or without prey. Otherwise hunting involved them moving into shallow water (c. 0.2 m deep), and walking along the substrate feeling for prey with their forefeet. Disturbed possible prey items were then caught with the forefeet.     

Seasonal changes in the invertebrate community of small shallow ephemeral pans at Bain's Vlei, South Africa

Changes in invertebrate population numbers and composition were monitored in six small shallow ephemeral pans during four consecutive inundations of spring, summer and autumn 1988/1989. The community was generally characterized by crustaceans and was invaded by insect larvae in summer. Community changes and succession were prominent in spring but less so in summer and autumn. Large pans supported more species than small pans. During longer inundation there was less difference between the initial and the final population composition than during shorter inundation, although the total population density did not increase significantly. This indicated that population composition stabilized as inundation lengthened. Population changes of six representative taxa were not correlated to changes in the physical and chemical characteristics of the water.     

Epifaunistic arthropod parasites of the four-striped mouse, Rhabdomys pumilio, in the Western Cape Province, South Africa

Flea, lice, mite, and tick species associated with 510 Rhabdomys pumilio were collected at 9 localities in the Western Cape Province, South Africa. The aims of the study were first to quantify the species richness, prevalence, and relative mean intensity of infestation of epifaunistic arthropod species associated with R. pumilio, and second to determine temporal variations in the mean abundance of the parasitic arthropods. Each mouse was examined under a stereoscopic microscope and its parasites were removed, identified, and quantified. The epifaunal population was made up of more than 25,000 individuals and included 8 flea, 1 sucking louse, 11 mite, and 13 ixodid tick species. Female-biased sex ratios were noted for 9 (30%) of the ectoparasite species. Three undescribed mite and 1 undescribed tick species were recovered, and new locality records for 2 flea, the louse, and 2 mite species were documented. A phoretic host association between a nonparasitic mite species, Psylloglyphus uilenbergi kivuensis, and 3 flea species, Chiastopsylla rossi, Hypsophthalmus temporis, and Listropsylla agrippinae, was recorded. The mean abundance of the parasitic mite and insect species were higher during the cold wet season, whereas ticks were more numerous during the warm dry months. The large number of ectoparasite species on R. pumilio, a locally abundant and regionally widespread species, is of medical and veterinary importance particularly in relation to the transmission of pathogens such as Anaplasma marginale, Babesia caballi, and Babesia canis to domestic animals; Rickettsia conori; Yersinia pestis; and the viral disease Crimean-Congo hemorrhagic fever to humans.     

Perceptions towards Egyptian Geese at the Steenberg Golf Estate,Cape Town,South Africa

The number of Egyptian Geese Alopochen aegyptiaca has increased in the Western Cape province, South Africa, during the past few decades and they are allegedly perceived as a problem on golf courses. However, attitudes towards the geese on golf courses in the province have not been empirically assessed. We surveyed the residents and members of the Steenberg Golf Estate, Cape Town, during April 2012 to evaluate perceptions towards Egyptian Geese on the estate. A standardised, anonymous questionnaire was sent to 548 estate residents and non-resident golfing members. Of the 112 respondents, the majority (92, or 84%) considered that geese are a problem on the estate. The ranking of the perceived problem was: 16 (15%) minimal problem, 34 (33%) moderate problem and 54 (52%) severe problem. The majority also considered that the goose population should be reduced by 50% or more (90, or 86% of all respondents). Dealing with Egyptian Geese numbers and activities on golf courses is complex. The option of designing golf courses and adjacent vegetation so that they are attractive to local bird species, while simultaneously being less attractive to Egyptian Geese, is available.