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Namibia
Kinds of Namibia Selected AbstractsVariability in sea-surface temperature and winds in the tropical south-east Atlantic Ocean and regional rainfall relationshipsINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 1 2009J. C. Hermes Abstract Variability in sea-surface temperature (SST) and winds in the Angola Benguela frontal zone (ABFZ) in the tropical south-east Atlantic Ocean has previously been shown to be important for regional fisheries and for seasonal rainfall anomalies over Angola/Namibia in austral summer and coastal West Africa in boreal summer. This study investigates intraseasonal variability in winds and SST over this region using QuikSCAT and tropical rainfall measuring mission (TRMM) satellite data for 1999,2004. Wavelet analyses reveal periods of relatively strong power in the 20,30 or 30,64 day frequency bands throughout the record but that there is substantial interannual variability in the occurrence of these intraseasonal oscillations. The implications of this variability for seasonal rainfall anomalies during the main rainy seasons in southern Africa (austral summer) and coastal West Africa (boreal summer) are discussed. Copyright © 2008 Royal Meteorological Society [source] NAMIBIA: Bank Crimes UpAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 3 2010Article first published online: 4 MAY 2010 No abstract is available for this article. [source] NAMIBIA,INDIA: Cooperation on Minerals and EnergyAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 8 2009Article first published online: 1 OCT 200 No abstract is available for this article. [source] NAMIBIA: Signs of RecoveryAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 8 2009Article first published online: 1 OCT 200 No abstract is available for this article. [source] A Test of Wills: Jimmy Carter, South Africa, and the Independence of NamibiaDIPLOMATIC HISTORY, Issue 5 2010Piero Gleijeses Until 1975, Washington paid little attention to southern Africa, a backwater in the Cold War where weak insurgencies posed little threat to white rule in Angola, Mozambique, Rhodesia, and Namibia. The collapse of the Portuguese dictatorship in April 1974 meant the end of white rule in Angola and Mozambique. The Cuban victory in Angola the following year propelled southern Africa into the vortex of the Cold War. Between 1977 and 1981, the Carter administration engaged in a complicated minuet with South Africa and the Namibian rebels to craft a negotiated settlement that would grant Namibia its independence. Secretary of State Cyrus Vance and National Security Adviser Zbigniew Brzezinski clashed over the course the United States should follow, while Cuba and the Soviet Union strongly supported the Namibian insurgents and 20,000 Cuban soldiers were poised in neighboring Angola. I analyze the failure of Carter's Namibia policy based on US, Cuban and South African documents, as well as interviews with Namibian, US, Cuban and South African protagonists. [source] Sources of sulphur in gypsiferous sediments and crusts and pathways of gypsum redistribution in southern TunisiaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 12 2004Nick A. Drake Abstract Southern Tunisia contains one of the most extensive gypsum accumulations in Africa comprising Triassic, Cretaceous, Eocene and Mio-Pliocene marine evaporites, spring deposits, playa sediments, aeolian sands and gypsum crusts. Sulphur isotope analysis (,34S) of bedrock samples, groundwater, playa brines, playa sediments, and gypsiferous crusts provides insight into the sources of gypsum in the region and sheds light on the processes that lead to gypsum crust formation. Results suggest that recycling of marine gypsum is the most likely source of the sulphate in the groundwater, playa sediments and crusts. The low ,34S values found in Eocene and Mio-Pliocene samples suggest that this recycling has been going on for millions of years. Though bedrock appears to be the ultimate source of the gypsum in the crusts, transport of this sulphate to playas, concentration therein, and subsequent dispersal across the landscape by aeolian processes provides the most likely pathway for sur,cial gypsum crust formation. Comparison of these results with those from Australia, Chile and Namibia suggests that, although the source of the sulphur varies from region to region, the processes of sur,cial crust formation appear to be similar. Copyright © 2004 John Wiley & Sons, Ltd. [source] The nature of calcareous deposits along pan margins in eastern central NamibiaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 7 2002Florias MeesArticle first published online: 13 JUN 200 Abstract In a region along the western margin of the Kalahari in eastern Namibia and western Botswana, many pan basins have mainly calcareous deposits along part of their margins. These are typically lined by low vertical scarps. In Namibia, these pans are mainly located in dry river beds. The petrographical study of these deposits demonstrates that they consist of lacustrine sediments that have to a varying extent been affected by early-diagenetic processes and by the formation of late-diagenetic features. The original composition of the deposits ranges from highly calcareous sediments, typically with ostracod, diatom and charophyte remains, to entirely non-calcareous diatomites. The deposits generally show an upward increase in total carbonate content, which is mainly a synsedimentary feature. The early-diagenetic processes that affected the deposits include the formation of orthic siliceous nodules. At a later stage, secondary calcite enrichment occurred, leaving only the silica-impregnated sections unaffected. This enrichment partly accounts for the upward increase in total carbonate content in some profiles and often resulted in the development of a highly calcareous surface horizon. Sepiolite and amorphous silica that are part of the groundmass of the deposits may also partly have formed at this stage. Late-diagenetic features include various forms of secondary calcite and silica. This study of pan basins in eastern central Namibia indicates that a lacustrine rather than purely pedogenic origin should also be considered for calcareous deposits that commonly occur along pan margins in other parts of southern Africa. Copyright © 2002 John Wiley & Sons, Ltd. [source] Introducing size limits as a management tool for the recreational line fishery of silver kob, Argyrosomus inodorus (Griffiths and Heemstra), in Namibian watersFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2001C. H. Kirchner Individual silver kob Argyrosomus inodorus (Griffiths and Heemstra) first mature at just over 1 yr of age and the median age at maturity is approximately 1.5 yr. Spawning of silver kob was observed in the southern and central region of the stock's range, but little spawning activity was found in silver kob sampled from the northern region. The spawning period is protracted over 6 months (October,March), which coincides with warmer water temperatures (>15 °C) and the occurrence of large-sized spawning silver kob in the southern and central part of Namibia. Implementing a minimum size limit for the silver kob fishery is not recommended as it will have serious economic implications for the coastal communities. The protection of the spawning areas, Meob Bay and Sandwich, should be continued and a strict bag limit on large-sized silver kob is recommended for the Namibian silver kob recreational fishery. [source] Nation Building and Women: The Effect of Intervention on Women's AgencyFOREIGN POLICY ANALYSIS, Issue 1 2008Mary Caprioli Regardless of the primary motive, international military intervention aimed at nation building is partly intended to establish democratic societies. And scholars have demonstrated that intervention does have a positive impact on democratization. With democratization generally follows greater support for human rights. Feminist scholars, however, have questioned definitions of democracy in which at minimal, women's political rights are absent. This brings into question the impact of intervention on the status of women. Particularly in both Iraq and Afghanistan women's rights have become prominent in the post-invasion American political rhetoric. Since intervention seems to be associated with the spread of democratic principles, we seek to discover whether intervention actually moves societies toward gender equality. We examine all six cases of completed military intervention aimed at nation building in sovereign states during the post Cold War period. Three of the cases,El Salvador, Mozambique, Namibia,evidence democratic change; whereas, the remaining three states,Cambodia, Haiti, Somalia,remain undemocratized. We test the extent to which intervention has or has not improved women's equality and find no dramatic effect, either positive or negative, of intervention on the status of women in any of the six states. [source] Endemic species and ecosystem sensitivity to climate change in NamibiaGLOBAL CHANGE BIOLOGY, Issue 5 2006WILFRIED THUILLER Abstract We present a first assessment of the potential impacts of anthropogenic climate change on the endemic flora of Namibia, and on its vegetation structure and function, for a projected climate in ,2050 and ,2080. We used both niche-based models (NBM) to evaluate the sensitivity of 159 endemic species to climate change (of an original 1020 plant species modeled) and a dynamic global vegetation model (DGVM) to assess the impacts of climate change on vegetation structure and ecosystem functioning. Endemic species modeled by NBM are moderately sensitive to projected climate change. Fewer than 5% are predicted to experience complete range loss by 2080, although more than 47% of the species are expected to be vulnerable (range reduction >30%) by 2080 if they are assumed unable to migrate. Disaggregation of results by life-form showed distinct patterns. Endemic species of perennial herb, geophyte and tree life-formsare predicted to be negatively impacted in Namibia, whereas annual herb and succulent endemic species remain relatively stable by 2050 and 2080. Endemic annual herb species are even predicted to extend their range north-eastward into the tree and shrub savanna with migration, and tolerance of novel substrates. The current protected area network is predicted to meet its mandate by protecting most of the current endemicity in Namibia into the future. Vegetation simulated by DGVM is projected to experience a reduction in cover, net primary productivity and leaf area index throughout much of the country by 2050, with important implications for the faunal component of Namibia's ecosystems, and the agricultural sector. The plant functional type (PFT) composition of the major biomes may be substantially affected by climate change and rising atmospheric CO2, currently widespread deciduous broad leaved trees and C4 PFTs decline, with the C4 PFT particularly negatively affected by rising atmospheric CO2 impacts by ,2080 and deciduous broad leaved trees more likely directly impacted by drying and warming. The C3 PFT may increase in prominence in the northwestern quadrant of the country by ,2080 as CO2 concentrations increase. These results suggest that substantial changes in species diversity, vegetation structure and ecosystem functioning can be expected in Namibia with anticipated climate change, although endemic plant richness may persist in the topographically diverse central escarpment region. [source] Of squeezers and skippers: factors determining the age at moult of immature African Penguins Spheniscus demersus in NamibiaIBIS, Issue 2 2005JESSICA KEMPER We used banding and resighting records of 391 African Penguins Spheniscus demersus banded as chicks and later resighted during immature moult to explain the roles of date of fledging and age at moult in determining the season of moult and its timing within the season. Breeding was continuous, but immature moult occurred mainly during spring and summer. Age at immature moult extended over 11 months, from 12 to 23 months after hatching. Birds that fledged during summer and early autumn generally moulted during the next moult season (squeezers), whereas birds that fledged in late autumn, winter and spring skipped the next moult season to moult only the following season (skippers). There was a significant relationship between age at moult and moult date, with young birds moulting later in the season than older birds. The age at moult of immature birds appears to be constrained by minimum age, moult seasonality and plumage wear. Birds that fledged over nearly 2 years moult during one season. Counts of moulting immature African Penguins have not been used to estimate year-class strength and post-fledging survival owing to the wide range of ages at immature moult. Our results provide the means of assigning recruits to specific age groups. [source] Dispersal and migration of juvenile African Black Oystercatchers Haematopus moquiniIBIS, Issue 3 2003Philip A. R. Hockey African Black Oystercatchers Haematopus moquini are sedentary as adults. However, colour-ringing of more than 700 juveniles has revealed complex post-fledging movements that vary geographically. Young from the western part of the breeding range either remain within 150 km of their natal site or migrate 1500,2000 km to one of five discrete nursery areas on the Namib Desert coast of central and northern Namibia, and southern Angola. These nurseries all lie north of the species' breeding range. We calculate that 36,46% of all juveniles born in South Africa migrate to nurseries. Birds return to their natal sites from nurseries at 2,3 years old, but never migrate again. Juveniles from the eastern part of the range undertake ,diffusion dispersal', regularly up to 1000 km, but these journeys mostly end within the breeding range, where there are no nurseries. Very few eastern birds reach nurseries. There is no evidence that movements of western birds are density-dependent responses to hatching date, but long-distance migrants are significantly heavier as chicks than are short-distance dispersers. We hypothesize that a genetic basis exists to these movements, possibly triggered by body condition, that could account not only for the highly dichotomous behaviour of western birds, but also for the intermediate behaviour of eastern birds. [source] Islands in a desert: breeding ecology of the African Reed Warbler Acrocephalus baeticatus in NamibiaIBIS, Issue 4 2001CORINE M. EISING The continental African Reed Warbler Acrocephalus baeticatus, like its relative the Seychelles Warbler Acrocephalus sechellensis, breeds in isolated patches. We studied the mating system of the African Reed Warbler to see whether this species, like the Seychelles Warbler, shows co-operative breeding. The African Reed Warbler is not polygynous. The majority breed monogamously (88%, n= 65), however in 12% of the territories three adult unrelated birds (mostly males) were observed participating in the brooding and feeding of nestlings, suggesting a polyandrous breeding system. Multilocus DNA fingerprinting revealed that the helping bird was unrelated to the pair birds. The percentage of nests with helpers was low compared to rates found in the Seychelles Warbler or Henderson Reed Warbler Acrocephalus vaughani taiti. This could be due to the scarcity of potential helpers or to the fact that, although limited, birds still had the opportunity to disperse within a meta-population structure in search of vacant territories. The presence of helpers was associated with increased hatching success due to lower predation rates, but not with increased fledging success. Another possible benefit of helping behaviour in this species could be improved predator detection and mobbing. Nest predation was high and warblers tended to build their nests in the highest, most dense reed patches available in their territory. There was no relation between habitat quality, measured as insect food availability, and the occurrence of helpers. [source] Solar radiation climate change over southern Africa and an assessment of the radiative impact of volcanic eruptionsINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 3 2005H. C. Power Abstract Spatial and temporal variability in global, diffuse, and horizontal direct irradiance and sunshine duration has been evaluated at eight stations in South Africa and two stations in Namibia where the time series range between 21 and 41 years. Global and direct irradiance and sunshine duration decrease from northwest to southeast; diffuse irradiance increases toward the east. Annually averaged global irradiance Ga decreased between 1.3% (2.8 W m,2) and 1.7% (4.4 W m,2) per decade at Bloemfontein, Cape Town, Durban, Pretoria, and Upington. Annually averaged diffuse irradiance Da decreased 5.2% (3.0 W m,2) per decade at Grootfontein and 4.2% (3.1 W m,2) per decade at Port Elizabeth. Annual direct irradiance Ba decreased 2.1% (3.5 W m,2) per decade at Cape Town and 2.8% (5.7 W m,2) per decade at Alexander Bay. A simultaneous decrease in annually averaged daily sunshine duration Sa may have contributed to the decrease in Ba at Alexander Bay and the decrease in Ga at Pretoria. Increases in aerosols may have contributed to the observed decrease in Ga at Cape Town and Durban, and the decrease in Da at Grootfontein may be due to a decrease in aerosols. On average, variability in Sa explains 89.0%, 50.4%, and 89.5% of the variance in Ga, Da, and Ba respectively. The radiative response to changes in sunshine duration is greater for direct irradiance than for global and diffuse. In the 2 years following the 1963 Mount Agung eruption in Indonesia, changes in global irradiance over southern Africa were small and inconsistent. At eight stations, diffuse irradiance increased 21.9% (13.3 W m,2) on average and direct irradiance decreased 8.7% (15.5 W m,2). After the 1982 El Chichón eruption in Mexico, global irradiance increased at two stations and decreased at seven stations. Eight stations witnessed an increase in diffuse irradiance averaging 7.2% (4.0 W m,2) and a decrease in direct irradiance of 5.0% (9.0 W m,2). The contribution of changes in cloud cover to the observed changes in irradiances appears to be small. Following the 1991 Mount Pinatubo eruption in the Philippines, diffuse irradiance increased an average of 18.8% (10.0 W m,2) at three stations and direct irradiance decreased by 7.2% (13.0 W m,2). Copyright © 2005 Royal Meteorological Society [source] Namibia: Selected Economic Indicators, 2005,10AFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 8 2010Article first published online: 30 SEP 2010 No abstract is available for this article. [source] METHODOLOGICAL INSIGHTS: Using seismic sensors to detect elephants and other large mammals: a potential census techniqueJOURNAL OF APPLIED ECOLOGY, Issue 3 2005JASON D. WOOD Summary 1Large mammal populations are difficult to census and monitor in remote areas. In particular, elephant populations in Central Africa are difficult to census due to dense forest, making aerial surveys impractical. Conservation management would be improved by a census technique that was accurate and precise, did not require large efforts in the field, and could record numbers of animals over a period of time. 2We report a new detection technique that relies on sensing the footfalls of large mammals. A single geophone was used to record the footfalls of elephants and other large mammal species at a waterhole in Etosha National Park, Namibia. 3Temporal patterning of footfalls is evident for some species, but this pattern is lost when there is more than one individual present. 4We were able to discriminate between species using the spectral content of their footfalls with an 82% accuracy rate. 5An estimate of the energy created by passing elephants (the area under the amplitude envelope) can be used to estimate the number of elephants passing the geophone. Our best regression line explained 55% of the variance in the data. This could be improved upon by using an array of geophones. 6Synthesis and applications. This technique, when calibrated to specific sites, could be used to census elephants and other large terrestrial species that are difficult to count. It could also be used to monitor the temporal use of restricted resources, such as remote waterholes, by large terrestrial species. [source] ECONOMIC TRENDS: Namibia: Return to GrowthAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 7 2010Article first published online: 1 SEP 2010 No abstract is available for this article. [source] Zoogeography of the southern African ascidian faunaJOURNAL OF BIOGEOGRAPHY, Issue 12 2004Carmen Primo Abstract Aim, To describe the biogeography of the ascidian fauna of southern Africa, to compare the results obtained with those reported for other fauna and flora of the same region, and to speculate about the origin of ascidians in the region. Location, Southern Africa extending over 4000 km from Mossâmedes (15° S,12° E) to Inhaca Island (26°30, S,33° E), including Vema Seamount (31°40, S,8 °20, E), Amsterdam-Saint Paul Islands (38° S,77°30, E) and the Tristan-Gough Islands (38° S,12°20, W). Methods, We constructed a presence/absence matrix of 168 species for 26 biogeographical divisions, 21 classical biogeographical regions described by Briggs (Marine zoogeography, McGraw-Hill, New York, 1974) and five provinces within the southern African region. We considered the following limits and divisions into provinces for the southern African region: Namibia, Namaqua, Agulhas and Natal as proposed by Branch et al. (Two oceans. A guide to the marine life of southern Africa, David Philip Publishers, 1994), and the West Wind Drift Islands province (WWD) according to Briggs (Global biogeography, Elsevier Health Sciences, Amsterdam, 1995). To examine the biogeographical structure, species and divisions were classified using cluster analysis (based on UPGMA as the aggregation algorithm) with the Bray,Curtis index of similarity. This classification was combined with MDS ordination. Main conclusions, Four main groups were obtained from the analysis of affinities among species: (1) species present in the WWD, separated by a high percentage of endemisms and a low number of species with a southern African distribution. Moreover, in the light of the species distribution and the results of further analysis, which revealed that they are completely separated and not at all related to the southern African region, it appears that there are no close relationships among the different islands and seamounts of the West Wind Drift Island province. This province was therefore removed from the remaining analyses; (2) species with a wide distribution; (3) species of colder waters present in Namaqua and Agulhas provinces, a transitional temperate area in which gradual mixing and replacement of species negate previous hypotheses on the existence of a marked distributional break at Cape of Good Hope; (4) species of warmer waters related to Natal province. The classification into biogeographical components was dominated by the endemic (47%), Indo-Pacific (25%) and cosmopolitan (13%) components. The analysis of affinities among biogeographical areas separated Namibia from the rest of the southern African provinces and showed that it was related to some extent to the Antarctic region because of the cold-temperate character of the province and the low sampling effort; Namaqua, Agulhas and Natal were grouped together and found to be closely related to the Indo-West Pacific region. In general, our results were consistent with those obtained for other southern African marine invertebrates. The frequency distribution of solitary/colonial strategies among provinces confirmed the domination of colonial organisms in tropical regions and solitary organisms in colder regions. Finally, we speculate that the southern African ascidian fauna mainly comprises Indo-Pacific, Antarctic and eastern Atlantic ascidians. [source] PORTS AND SHIPPING: NamibiaAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 6 2009Article first published online: 30 JUL 200 No abstract is available for this article. [source] Daily and hourly movement of male desert-dwelling elephantsAFRICAN JOURNAL OF ECOLOGY, Issue 1 2010Keith Leggett Abstract The daily and hourly movements of eight male desert-dwelling elephants of various ages (12,45 years old) were determined hourly by global positioning system (GPS)/telemetry collars during the wet, cold dry and hot dry seasons of 2006 in northwest Namibia. The average daily movement in the wet season was greater than that observed during either the cold dry or the hot dry seasons. A similar difference was also observed for the movement rates, with the highest average rate of hourly movement recorded during the wet season. The diurnal movements (both distance and rate) were greater than those in the nocturnal hours during the wet season, whilst during the cold dry and hot dry season the reverse was true. The daily cycle of movement also changed seasonally, with greatest movement rates observed during the wet season between 11.00,20.00 hours, during the cold dry season between 14.00,21.00 hours; and between 04.00,11.00 hours during the hot dry season. Periods of decreased movement rates were observed between 09.00,10.00 and 02.00,03.00 hours in the wet season; 03.00,06.00 and 11.00,13.00 hours in the cold dry season; and 01.00,03.00 and 12.00,14.00 hours during the hot dry season. Résumé On a suivi heure par heure les déplacements quotidiens de huit éléphants du désert mâles, d'âge divers (12 à 45 ans), grâce à des colliers GPS (système de positionnement mondial) et télémétriques, au cours des saisons des pluies, sèche chaude et sèche froide de 2006, dans le nord-ouest de la Namibie. Le déplacement quotidien moyen durant la saison des pluies était supérieur à ceux observés en saison sèche froide ou en saison sèche chaude. Une différence semblable fut aussi observée pour le taux de déplacement, le taux moyen le plus élevé par l'heure étant enregistré pendant la saison des pluies. Les mouvements diurnes (aussi bien leur distance que leur rythme) étaient plus grands que les mouvements nocturnes en saison des pluies, alors que pendant la saison sèche froide et la saison sèche chaude, c'était l'inverse. Le cycle quotidien des déplacements changeait aussi avec les saisons, le rythme étant plus élevé en saison des pluies entre 11h00 et 20h00; en saison sèche froide entre 14h00 et 21h00; et en saison sèche chaude entre 04h00 et 11h00. On a observé des périodes de rythme ralenti entre 21h00 et 04h00 en saison des pluies; entre 03h00 et 05h00 et entre 11h00 et 13h00 en saison sèche froide; et entre 01h00 et 03h00 et entre 12h00 et 14h00 en saison sèche chaude. [source] Genetic structure of two populations of the Namibian giraffe, Giraffa camelopardalis angolensisAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Rick A. Brenneman Abstract Two geographically distinct populations of giraffe (Giraffa camelopardalis) were sampled for this study, the northern Namib Desert and Etosha National Park. Population genetic parameters and relationships within subpopulations were estimated to better understand the genetic architecture of this isolated subspecies. Gene flow between the geographically separated populations can be attributed to recent translocation of giraffe between the two populations. Inbreeding estimates in the six subpopulations studied were low though we found evidence that genetic drift may be affecting the genetic diversity of the isolated populations in northern Namibia. Population dynamics of the sampling locations was inferred with relationship coefficient analyses. Recent molecular systematics of the Namibian giraffe populations indicates that they are distinct from the subspecies Giraffa camelopardalis giraffa and classified as G. c. angolensis. Based on genetic analyses, these giraffe populations of northern Namibia, the desert-dwelling giraffe and those protected in Etosha National Park, are a distinct subspecies from that previously assumed; thus we add data on G. c. angolensis to our scientific knowledge of this giraffe of southern Africa. Résumé Deux populations de girafes (Giraffa camelopardalis) distinctes sur le plan géographique ont servi d'échantillons pour cette étude, celle du nord du Désert du Namib et celle du Parc National d'Etosha. Nous avons estimé les paramètres génétiques des populations et les relations au sein des sous-populations pour mieux comprendre l'architecture génétique de cette sous-espèce isolée. Les flux génétiques entre les populations séparées géographiquement peuvent être attribués à la récente translocation de girafes entre ces deux populations. L'inbreeding estimé dans les six sous-populations étudiées était faible, encore que nous ayons découvert des preuves que la dérive génétique pourrait bien affecter la diversité génétique des populations isolées dans le nord de la Namibie. La dynamique des populations des endroits où furent faits les échantillonnages fut déduite en fonction de l'analyse des coefficients. La nouvelle systématique moléculaire des populations de girafes de Namibie indique qu'elles sont distinctes de la sous-espèce Giraffa camelopardalis giraffa et classées comme G.c. angolensis. Selon les analyses génétiques, ces populations de girafes du nord de la Namibie, les girafes qui vivent dans le désert et celles qui sont protégées dans le Parc National d'Etosha sont une sous-espèce distincte de celle que l'on croyait auparavant, et nous ajoutons ainsi des données sur G.c. angolensisà la connaissance scientifique de cette girafe d'Afrique australe. [source] Preliminary observations of the diet of the black mongoose (Galerella nigrata, Thomas, 1928) in the Erongo Mountains, NamibiaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Ymke Warren No abstract is available for this article. [source] Elephants caught in the middle: impacts of war, fences and people on elephant distribution and abundance in the Caprivi Strip, NamibiaAFRICAN JOURNAL OF ECOLOGY, Issue 2 2009Michael J. Chase Abstract We conducted wet [26 March,4 April 2003 (Apr03)] and dry [1,8 November 2005 (Nov05)] season aerial surveys of African elephants (Loxodonta africana Blumenbach) in the Caprivi Strip, Namibia to provide an updated status report on elephant numbers and distribution and assist with a historical analysis of elephant distribution and abundance in the Caprivi Strip. During the wet season when water was available in seasonal pans, elephants were widely distributed throughout the survey area. In contrast, during the dry season, a majority of elephant herds occurred within 30 km of the perennial Kwando, Linyanti and Okavango rivers and few herds occurred within the West Caprivi Game Reserve where water in the seasonal pans was limited. We estimated 5318 elephants for the 7731-km2 survey area (0.71 elephants km,2) for the Apr03 wet season survey and 6474 elephants for the 8597-km2 survey area (0.75 elephants km,2) for the Nov05 dry season survey. Based on our aerial surveys and reports of elephant numbers and distribution from historical aerial surveys and telemetry studies, civil war, veterinary fences and human activities appear to have effected changes in African elephant abundance, distribution and movements in the Caprivi Strip, Namibia since 1988 when the first comprehensive aerial surveys were conducted. Résumé En saison des pluies (avril 2003) et en saison sèche (novembre 2005), nous avons réalisé des contrôles aériens des éléphants africains (Loxodonta africana Blumenbach) dans la Bande de Caprivi, en Namibie, pour pouvoir fournir un rapport actualisé sur le statut du nombre et de la distribution des éléphants, et aider une analyse de longue durée de la distribution et de l'abondance des éléphants dans la Bande de Caprivi. Pendant la saison des pluies, lorsque l'eau était disponible dans les « pans » saisonniers, les éléphants étaient largement distribués dans toute la zone étudiée. Par contre, en saison sèche, la grande majorité des troupeaux d'éléphants se trouvaient dans les 30 km des rivières permanentes Kwando, Linyanti et Okavango, et peu de troupeaux se trouvaient dans la West Caprivi Game Reserve, où l'eau était limitée dans les pans saisonniers. Nous avons estimé le nombre d'éléphants à 5 318 dans les 7 731 km² de la zone étudiée (0,71 éléphant km,²) pour l'étude faite en saison des pluies d'avril 2003, et à 6 474 éléphants dans les 8 597 km²étudiés (0,75 éléphant km,²) pendant la saison sèche de novembre 2005. En se basant sur nos contrôles aériens et sur des rapports concernant le nombre et la distribution des éléphants provenant de contrôles aériens et d'études télémétriques anciens, il s'avère que la guerre civile, les barrières vétérinaires et les activités humaines ont provoqué des changements de l'abondance, de la distribution et des déplacements des éléphants dans la Bande de Caprivi depuis 1988, date où les premiers contrôles aériens complets ont été effectués. [source] A conservation assessment of the freshwater crabs of southern Africa (Brachyura: Potamonautidae)AFRICAN JOURNAL OF ECOLOGY, Issue 1 2008Neil Cumberlidge Abstract Recent taxonomic revisions of the freshwater crabs of southern Africa (Angola, Botswana, Lesotho, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe) allow accurate depictions of their diversity, distribution patterns and conservation status. The southern African region is home to nineteen species of freshwater crabs all belonging to the genus Potamonautes (family Potamonautidae). These crabs show high levels of species endemism (84%) to the southern African region and to the country of South Africa (74%). The conservation status of each species is assessed using the IUCN (2003) Red List criteria, based on detailed compilations of the majority of known specimens. The results indicate that one species should be considered vulnerable, fifteen species least concern and three species data deficient. The results have been utilized by the IUCN for Red Lists, and may prove useful when developing a conservation strategy for southern Africa's endemic freshwater crab fauna. Résumé De récentes révisions de la taxonomie des crabes d'eau douce d'Afrique australe (Afrique du Sud, Angola, Botswana, Lesotho, Mozambique, Namibie, Swaziland, Zambie et Zimbabwe) permettent des descriptions précises de leur diversité, de leur schéma de distribution et de leur statut de conservation. L'Afrique australe accueille 19 espèces de crabes d'eau douce qui appartiennent toutes au genre Potamonautes (famille des Potamonautidae). Ces crabes présentent un degréélevé d'endémisme spécifique (84%) pour la région de l'Afrique australe et pour l'Afrique du Sud elle-même (74%). Le statut de conservation de chaque espèce est évalué selon les critères de la Liste rouge de l'UICN (2003), en se basant sur des compilations détaillées de la majorité des spécimens connus. Les résultats montrent qu'une des espèces devrait être considérée comme «vulnérable», 15 autres comme «préoccupation mineure» et trois n'ont que des «données insuffisantes». Les résultats ont été utilisés par l'UICN pour la Liste rouge et peuvent s'avérer utiles pour le développement d'une stratégie de conservation pour la faune des crabes d'eau douce endémiques d'Afrique australe. [source] Seasonal occurrence and local movements of the grey-headed (brown-necked) parrot Poicephalus fuscicollis suahelicus in southern AfricaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2003Craig T. Symes Abstract Seasonal movements of grey-headed (brown-necked) parrots were recorded in parts of its range and are likely a response to breeding and availability of specific food sources. Breeding occurred in the northern Kruger National Park and lowveld near the Mutale,Luvhuvhu river confluence from April to August. Aggregations and movements of birds occurred during the post-breeding season (August,December) in response to seasonally abundant food sources. In north-eastern South Africa, grey-headed parrots occurred at Levubu, following the breeding season and their arrival in the area was correlated with the availability of unripe Mabola Plum, Parinari curatellifolia fruit. Similar regional movements occurred in Zimbabwe, the Caprivi of northern Namibia and Zambia. During these movements, flocks of up to 50 individuals were observed, whilst during breeding months singletons and pairs were more frequently seen. This increased abundance in time and space suggests that seasonal migratory movements occur. Résumé Des déplacements saisonniers de perroquets Poicephalus robustus ont été relevés dans des parties de leur aire de répartition, et ils sont vraisemblablement une réponse aux besoins de la reproduction et à la disponibilité des sources de leur nourriture spécifique. La reproduction avait lieu d'avril à août dans le nord du Parc National Kruger et dans le lowveld près du confluent des rivières Mutale et Luvhuvhu. Des rassemblements et des déplacements d'oiseaux avaient lieu dans la saison qui suivait celle de la reproduction (août , décembre) en réponse à l'abondance saisonnière des sources de nourriture. Au nord-est de l'Afrique du Sud, ces perroquets se rencontraient à Levubu, après la saison de reproduction, et leur arrivée coïncidait à la disponibilité des prunes Mabola (Parinari curatellifolia) avant leur maturité. On constatait des déplacements régionaux saisonniers semblables au Zimbabwe, dans le Capríví au nord de la Namibie et en Zambie. Au cours de ces déplacements, on a observé des bandes qui peuvent compter jusqu'à 50 individus, alors que pendant les mois de reproduction, on voyait plus souvent des solitaires ou des couples. Cette abondance accrue à certains moments et à certains endroits suggère qu'il existe des migrations saisonnières. [source] The influence of multi-scale environmental variables on the distribution of terricolous lichens in a fog desertJOURNAL OF VEGETATION SCIENCE, Issue 6 2006Jennifer S. Lalley Abstract Question: How do environmental variables in a hyper-arid fog desert influence the distribution patterns of terricolous lichens on both macro- and micro-scales? Location: Namib Desert, Namibia. Methods: Sites with varying lichen species cover were sampled for environmental variables on a macro-scale (elevation, slope degree, aspect, proximity to river channels, and fog deposition) and on a micro-scale (soil structure and chemistry). Macro-scale and micro-scale variables were analysed separately for associations with lichen species cover using constrained ordination (DCCA) and unconstrained ordination (DCA). Explanatory variables that dominated the first two axes of the constrained ordinations were tested against a lichen cover gradient. Results: Elevation and proximity to river channels were the most significant drivers of lichen species cover in the macro-scale DCCA, but results of the DCA suggest that a considerable percentage of variation in lichen species cover is unexplained by these variables. On a micro-scale, sediment particle size explained a majority of lichen community variations, followed by soil pH. When both macro and micro-scale variables were tested along a lichen cover gradient, soil pH was the only variable to show a significant relationship to lichen cover. Conclusion: The findings suggest that landscape variables contribute to variations in lichen species cover, but that stronger links occur between lichen growth and small-scale variations in soil characteristics, supporting the need for multi-scale approaches in the management of threatened biological soil crust communities and related ecosystem functions. [source] Population structure and history of southern African scrub hares, Lepus saxatilisJOURNAL OF ZOOLOGY, Issue 2 2004U. Kryger Abstract Genetic differentiation among populations of the South African scrub hare Lepus saxatilis was examined using hypervariable mitochondrial DNA control region I (CR-I) sequences. Neighbour-joining analysis revealed a pattern that did not correspond to the current subspecies delineations. The CR-I sequence data delimit scrub hares into three major maternal lineages. The three phylogenetic assemblages exhibited different geographical distributions. AMOVA analyses and exact tests for population differentiation confirmed this phylogeographic partitioning. One lineage (SW) was confined to the south-western Cape, the second lineage (N) was exclusively found in the northern part of South Africa and in the neighbouring countries, and the third lineage (C) was predominant in the central parts of South Africa. This spatial distribution did not coincide with the ranges of the 10 described subspecies covered by our sampling regime. The lineages C and N overlapped in an area including eastern parts of South Africa and southern Namibia. The presence of both lineages in that area of overlap was interpreted as the result of secondary contact due to recent range expansions after the two lineages had undergone a population restriction approximately 18 000 years ago. Analyses of contemporary gene flow disclosed an exchange of migrants between N and C, which was biased towards a movement from C to N. The SW group represents a very distinct evolutionary lineage that has been isolated for more than 45 000 years. It does not exchange female migrants with the other two groups. Mismatch distribution analyses indicated sudden population size expansions in the history of all three populations. [source] Using environmental accounts to promote sustainable development: Experience in southern AfricaNATURAL RESOURCES FORUM, Issue 1 2003Glenn-Marie Lange Environmental accounts bring together economic and environmental information in a common framework to measure the contribution of the environment to the economy and the impact of the economy on the environment. They enable governments to set priorities, monitor economic policies more precisely, enact more effective environmental regulations and resource management strategies, and design more efficient market instruments for environmental policies. This article uses examples from the regional environmental accounting programme in southern Africa to demonstrate the usefulness of environmental accounts to policy-making and natural resource management. The examples address the contribution of natural capital endowments (minerals and fisheries) to sustainable development in Botswana and Namibia; the economic importance of non-market forest goods and services in South Africa; and the socio-economic impact of current water allocation and pricing policies in Botswana, Namibia and South Africa. While there are many additional policy applications, these few provide a powerful argument for the use of environmental accounts in all countries. [source] Defiant desire in Namibia: Female sexual,gender transgression and the making of political beingAMERICAN ETHNOLOGIST, Issue 1 2008ROBERT LORWAY ABSTRACT In this article, I explore local productions of desire in Namibia by focusing on the engagement of young, working-class lesbians with human rights ideologies of sexual freedom. I discuss how various techniques deployed by a sexual minority-rights NGO allow youth to amplify and legitimize their embodied sense of sexual,gender difference. In my analysis of their self-mediated incitement, I regard desire as a moral practice; practices of self-determination and acts of resistance are generated and authenticated through repeated reflection on the internality of desire. My elaborations also emphasize class-related issues. I argue that struggles with class and gender inequality destabilize the very notion of "sexual identity" in ways that open up political and erotic possibilities between lesbians and other working-class women in Namibia, blurring the dividing lines of identity politics and of gender and class politics. [lesbian resistance, African sexuality, moral practice, desire, global queer identity, human rights] [source] Underground Vendobionta From NamibiaPALAEONTOLOGY, Issue 1 2002Dmitri Grazhdankin The late Precambrian fossils from Namibia have generally been regarded as soft-bodied organisms whose three-dimensional preservation resulted from smothering in fluidized sand. The sedimentological context of Pteridinium and Namalia within a sandstone bed, however, allows us to distinguish between two taphocoenoses: (1) winnowed, laterally collapsed, current-transported specimens accumulated as a lag deposit of turbidite-like flows, and (2) specimens ,floating' in the top part of an event bed with their vanes extending upwards to the upper bedding surface. The second taphocoenosis is interpreted as an in situ preserved ,infaunal' community. The immobile underground life habit and the bizarre modes of growth of Pteridinium and Namalia do not fit any extinct or modern group of multicellular organisms. Similar statements can be made for Ernietta and Rangea, thus reviving the Vendobionta hypothesis. [source] | ||||||||||||||||