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1.
M. D. Anderson 《Ostrich》2013,84(1-2):25-32
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.  相似文献   

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Hanzen  Céline  Lucas  Martyn C.  O’Brien  Gordon  Calverley  Peter  Downs  Colleen T. 《Hydrobiologia》2021,848(10):2579-2593
Hydrobiologia - Four freshwater eel species (Anguilla spp.) occur in southern African rivers that are increasingly anthropogenically modified. Information on movements, habitat use and overlap by...  相似文献   

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Aim To determine the spatial relationship between areas where different frog breeding groups occur and elevated anthropogenic activities, and the conservation implications thereof. Location South Africa. Methods Data on frog distribution ranges for the southern African sub‐region were used to identify biogeographical areas within South Africa. A random draw technique was used to determine whether areas where different frog breeding groups occur were characterized by higher levels of anthropogenic threats than expected by chance. Four measures (human population density, percentage land transformation, percentage protected area and invasive alien plants richness) expected to reflect threats were analysed. Results Terrestrial‐breeders were more often spatially associated with areas of threat than expected by chance in three of the seven biogeographical regions examined with land transformation and invasive alien plant richness being most significant. The south central was the only region where terrestrial‐breeders were spatially congruent with protected areas. Areas where stream‐breeders occur were spatially congruent with anthropogenic threats (with alien plants being most consistent) in five of the seven regions examined while protected areas were well represented in four of the seven regions. Non‐significant results were found for permanent and temporary aquatic‐breeders at both the national and the biogeographical scale. Main conclusions By analysing data at the sub‐continental scale we were able to identify regional threats to amphibians traditionally classified at species‐specific scales. Our study recognized land transformation and alien invasive plants as significant threats to areas important for the long‐term breeding success of stream and terrestrial amphibians in South Africa. Areas where different breeding groups occur in the south‐western Cape showed the greatest spatial congruence with the threats examined. Areas where terrestrial breeding frogs occur are not well represented in the current conservation network. This has important implications in addressing the current status of threats on amphibians in a biogeographical context.  相似文献   

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The spatial distribution of alien species richness often correlates positively with native species richness, and reflects the role of human density and activity, and primary productivity and habitat heterogeneity, in facilitating the establishment and spread of alien species. Here, we investigate the relationship between the spatial distribution of alien bird species, human density, and anthropogenic and natural environmental conditions. Next, we examined the relationship between the spatial distribution of alien bird species and native bird species richness. We examined alien species richness as a response variable, using correlative analyses that take spatial autocorrelation into account. Further, each alien bird species was examined as a response variable, using logistic regression procedures based on binary presence–absence data. A combination of human density and natural habitat heterogeneity best explained the spatial distribution of alien species richness. This contrasts with the results for individual alien species and with previous studies on other non-native taxa showing the importance of primary productivity and anthropogenic habitat modification as explanatory variables. In general, native species richness is an important correlate of the spatial distribution of alien species richness and individual alien species, with alien species being more similar to common species than to rare species.  相似文献   

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Local notions of conservation deserve closer scrutiny. We cannot assume that they naturally coincide with those of the tourist core; nor that they are automatically given higher priority when local populations are induced to participate in practices which conserve flora and fauna. A case study of the establishment of the Richtersveld National Park in Namaqualand, a remote arid region of South Africa, is used to argue that local attitudes to conservation and development (associated with tourism) can become increasingly cynical and ambivalent in the context of ecotourism. Furthermore, such attitudes are shaped less by economic inducements than by the often contradictory messages about conservation that are being communicated daily.  相似文献   

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This study investigated the utilization of mist‐belt grassland habitat by the threatened blue swallow and was conducted over three successive breeding seasons in the Blue Swallow Natural Heritage Site at Kaapsehoop, Mpumalanga, South Africa. Blue swallows significantly preferred wetlands over grasslands for foraging. Sufficient foraging habitat must be within a 1.5 km radius from an active nest site. The minimum size of a pair of blue swallows home range should be 333 ha, consisting at a minimum of grasslands (243 ha or 73%) and wetlands (90 ha or 27%). In order to conserve this threatened species, habitat transformation should not take place within a minimum radius of 1.5 km of any blue swallow nest. Due to the critical dependence of the blue swallow on wetland habitat for foraging, any development outside the 1.5 km radius that would affect hydrology and water quality within this range would need to be considered, and any adverse effect mitigated. Rehabilitation of areas to a grassland/wetland mosaic would rather quickly support foraging, and eventually breeding. Although a better understanding of the dynamics between wetlands and adjacent grasslands regarding blue swallow habitat requirements is needed, action can already be taken, based on our results.  相似文献   

7.
《Ostrich》2013,84(3):295-296
The Red-billed Quelea Quelea quelea is a serious pest of agricultural crops throughout most of sub-Saharan Africa. Since the 1980s, it has expanded its range into the Eastern Cape and Western Cape, South Africa, facilitated by changes in agricultural practices. This note documents the first breeding of Red-billed Quelea in the winter rainfall region of South Africa. A colony of 350–600 nests was found, with evidence of recent breeding. Red-billed Quelea numbers were low in this region, but if numbers increase in the future in the Western Cape, winter crops could be under threat.  相似文献   

8.
The breeding success of 18 groups of Arrowmarked Babblers Turdoides jardineii was followed in the 1992–1993 breeding season. The first eggs were laid in late October 1992 and the last eggs in February 1993. Group size was positively correlated with territory size. However, neither group size nor territory size was correlated with the number of offspring raised by a group. Extra adults in a group may not have enhanced the reproductive output of the breeding pair, but they helped in the defence and enlargement of a territory in a saturated habitat.  相似文献   

9.
Canine herpesvirus (CHV-1) causes neonatal deaths as well as infertility due to embryonal death, abortion and stillbirths in breeding kennels. The aim of this study was to determine the prevalence of antibodies against canine herpesvirus in the serum of dogs older than 1 year in breeding kennels in the Gauteng Province of South Africa. A serum neutralization test (SNT) and a newly developed enzyme linked immunosorbent assay (ELISA) were used to test the serum samples of 328 dogs in 38 breeding kennels. With SNT as well as ELISA, 22% of sera were positive (P>0.9). Seventeen kennels (45% of total kennels) each had at least one positive dog on SNT compared with twenty kennels (53% of total kennels) that each had at least one positive dog on ELISA (P=0.6). The prevalence of positive dogs in positive kennels was 42+/-26% (n=17 kennels) for SNT and 39+/-26% (n=20 kennels) for ELISA. Pairwise comparison of kennels showed that the prevalence of SNT positive dogs was similar to the prevalence of ELISA positive dogs (P=0.3, n=38 kennels). Seroprevalence was independent of age, gender or colony size. This study suggests that canine herpesvirus is sufficiently common in breeding dogs in the Gauteng Province of South Africa to pose a threat to neonatal survival and fertility.  相似文献   

10.
Andrew Jenkins 《Ostrich》2013,84(3-4):385-392
Jenkins, A.R. 2000. Factors affecting breeding success of Peregrine and Lonner Falcons in South Africa. Ostrich 71 (384): 385-392. Breeding success was recorded for three Peregrine Falcon, Falco peregrinus, populations in South Africa over nine years, and for Peregrine and Lanner Falcon, Ebiarmicus, populations in an area of sympatry over three years. The objectives of the study were to measure geographic and interspecific variation in reproductive performance, and determine environmental correlates of productivity. Territory occupancy, the frequency of breeding per occupied territory and clutch size did not vary significantly between the three Peregrine populations. However, Peregrine breeding success was generally lower on the Cape Peninsula (1. 11 young fledged per territorial poir), higher in the Soutpansberg (1.36) and highest on the Orange River (1.70). Overall, fledging rates of Soutpansberg Peregrines and Lanners were not significantly different, although annual productivity of the Lonner population was consistently higher. Neither species' breeding success was significantly depressed by the presence of close neighbouring pairs of the other, suggesting that they were not active competitors. Breeding performance of Peregrines on the Cape Peninsula correlated strongly with spring weather conditions: egg and hatchling survival was lower in wet years, and fledging rates were higher in warm years. Annual productivity of Orange River Peregrines correlated positively with the height of the river at the onset of breeding, and productivity of Soutpansberg Peregrines was higher in seasons following years of high rainfall. Elements of the physical structure of the nesting habitat (exposure of the nest ledge, height of the nest cliff) correlated positively with Peregrine breeding performance. Breeding success of Soutpansberg Lanners was largely unaffected by any of the environmental variables considered. Overall, it is proposed that Peregrine productivity reflected variation in the physical environment and its affect on prey availability.  相似文献   

11.
For more than a decade it has been internationally recognised that efforts should be made to remedy the concern that taxonomy is an endangered discipline in the grips of rapid decline. In acknowledgement of the perceived continuing marginalisation of taxonomy, the Darwin Declaration recognised the need to enhance the taxonomic capacity of members who are party to the CBD, and beyond. South Africa is one of the most biodiversity rich countries globally, and the unique and rich flora of the country brings with it a significant conservation imperative. Although the country, and southern African subregion for that matter, has a strong history of taxonomic endeavour, stretching back for over a century, it also suffers from a lack of human and other resources to adequately address its taxonomic needs. This inevitably calls for a process of priority-setting to ensure the wise use of available funding. As one example, it is shown that 1,009 indigenous South African plant taxa are regarded as Data Deficient for taxonomic reasons, following the completion of a recent comprehensive Red Listing exercise. Although not the only criterion to be considered when prioritising taxonomic research, efforts focused on these groups represent a significant opportunity for taxonomists to align their work with national priorities.  相似文献   

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Rapid biomonitoring protocols, using biotic indices based on macroinvertebrate diversity to assess river ecosystem health, are widely used globally. Such quick assessment techniques are lauded for the rapid results obtained and the relatively easy protocol used to achieve an answer. However, do such quick assessments of water quality give enough information about ecosystems? Are important details being overlooked? When should a full faunal survey be used in preference? Important research programmes, including environmental impact studies, often misuse biomonitoring techniques, making influential management decisions using superficial, low-level data obtained using biomonitoring tools, inappropriate to address those management objectives. The value of using biomonitoring as a quick tool, versus a more detailed faunal assessment, is considered here. The assessment of teloganodid mayfly fauna occurring in South African rivers provides an example of the value of detailed studies versus superficial family level investigations, showing that a rapid biomonitoring approach should not be used as a shortcut when a more detailed survey is needed. Each situation should be assessed for its own merit in a given set of project circumstances. A checklist of criteria is presented, giving guidance on when rapid biomonitoring alone is valuable and when more detailed assessments would give a more relevant result.  相似文献   

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South Africa's first national assessment of spatial priorities for biodiversity conservation, released in 2005, aimed to identify conservation priority areas for mainstreaming into all sectors at national and provincial scales. This National Spatial Biodiversity Assessment (NSBA) was based on a planning for implementation approach in order to deliver defensible products useful to decision-makers. The NSBA aimed to produce a map of broad-scale priority areas for future finer-scale assessment and conservation action. This map summarized information on species, ecosystems, ecological processes, and the pressures they face from human activities. Owing to the complexity of the priority area map, two additional user-friendly products — maps of ecosystem status and protection levels — were developed. These products represented the habitat loss and protected area coverage of South Africa's ecosystems relative to their conservation targets. A year after release, we reflect on the NSBA process, products and uptake by implementing agencies (with a specific focus on the terrestrial biodiversity assessment) in order to contribute to the growing body of documented best practice in conservation planning. The ecosystem status product has been widely used at national and provincial scales due in large to its clear and compelling message. The protection level and overall priority map have also witnessed uptake, the former in guiding the expansion of protected areas and the latter as an integrated map of national biodiversity status. The strong collaboration of local planners and implementers with in-depth experience of biodiversity assessment, using a systematic approach and focusing on communicating a few high level messages, appears to have contributed to the initial, successful uptake of the NSBA. We conclude with a call to address data and monitoring shortcomings before the next NSBA in 2010.  相似文献   

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Crawford, R.J.M., Dyer, B.M. & Upfold, L. 1999. Seasonal pattern of breeding by Cape and Crowned Cormorants off western South Africa. Ostrich 70(3&4): 193–195.

At Bird Island, Lambert's Bay, and Malgas Island, South Africa, small numbers of Cape Cormorants Phalacrocorax capensis may breed at any time of the year, but the main breeding season is from September to February. At Malgas Island, Crowned Cormorants P. coronatus may also breed throughout the year, but mostly from December to March. Counts of the breeding population of Cape Cormorants should be undertaken between October and December, and of Crowned Cormorants in January or February.  相似文献   

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