List of Titles

Karyology of three evolutionarily hexaploid southern African species of yellowfish, Labeobarbus Rüppel, 1836 (Cyprinidae)

- Naran, Daksha, Skelton, Paul H, Villet, Martin H

Authors: Naran, Daksha , Skelton, Paul H , Villet, Martin H
Date: 2007
Language: English
Type: Article
Identifier: vital:6855 , http://hdl.handle.net/10962/d1011138 , http://dx.doi.org/10.3377/1562-7020(2007)42[254:KOTEHS]2.0.CO;2
Description: The karyotypes of three species of yellowfish, namely Labeobarbus marequensis (A. Smith, 1841), L. capensis (A. Smith, 1841) and L. polylepis (Boulenger, 1907), were examined by Giemsa staining using an approach improved for the description of high chromosome numbers. In each case, 2n = 150; no heteromorphic chromosomes were detected; chromosomes in all morphological categories ranged smoothly from large to small, with no distinctly large submetacentric pairs; and metacentric chromosomes showed little variation in size. Labeobarbus marequensis had 26 metacentric (m), 44 submetacentric (sm), 42 subtelocentric (st) and 38 acrocentric (a) chromosomes and a fundamental number (FN) of 262; L. capensis had 16 m, 58 sm, 42 st and 34 a chromosomes and FN = 266; and L. polylepis had 18 m, 60 sm, 42 st and 30 a chromosomes and FN = 270. These results, combined with published literature, imply that Labeobarbus Rüppel, 1836 is an evolutionarily hexaploid African lineage and support its removal from synonymy with the evolutionarily tetraploid Asian genus Tor Gray, 1834. A review of fundamental numbers for conspecific Labeobarbus species examined in different studies implicated karyological technique as a confounding factor in assessing details of karyotypes, leading to recommendations for future karyological studies of barbine fishes. Potential synapomorphies are pointed out in karyological characters of species within Labeobarbus.
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Date Issued: 2007

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Nesting success and survival rates of suburban Olive Thrushes (Turdus olivaceus olivaceus).

- Bonnevie, Bo T

Authors: Bonnevie, Bo T
Date: 2007
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/448299 , vital:74720 , https://doi.org/10.2989/OSTRICH.2007.78.2.19.99
Description: Adult survival rates of suburban Olive Thrushes (Turdus olivaceus) were estimated from the proportion of adults and juveniles in mist-net samples from the Eastern Cape and Western Cape provinces of South Africa. These survival rates were compared to an estimate from recovery data. Reproductive rate, clutch size, nesting success and survival rate of dependent fledglings were estimated from breeding records in the Eastern Cape. These data were used to estimate survival rate of independent fledglings. The estimated adult survival rate in this region was high and the clutch size was small, compared to those of the Blackbird (Turdus merula) in Europe. Dispersal patterns from recapture and recovery data, and the relatively low survival rates of juvenile birds, suggest that fledglings are most vulnerable when they reach independence and leave their natal territories.
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Date Issued: 2007

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The status of the southern ground-hornbill in the Grahamstown region, Eastern Cape, South Africa

- Hulley, Patrick E, Craig, Adrian J F K

Authors: Hulley, Patrick E , Craig, Adrian J F K
Date: 2007
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/447909 , vital:74683 , https://www.tandfonline.com/doi/pdf/10.2989/OSTRICH.2007.78.1.13.57
Description: The Eastern Cape has been the southernmost limit of distribution for the Southern Ground-Hornbill Bucorvus leadbeateri throughout the period for which there are written records (Vernon 1986, Vernon and Herremans 1997). No records are known west of Port Elizabeth and the only ones from this 1 map square (33 S 27 E) date from the nineteenth century. Vernon (1986) noted that nest and roost sites for groundhornbills were in large trees or on cliffs, from which the birds commuted to forage in open country. The forest/thicket and grassland mosaic in the Eastern Cape is apparently ancient (Skead 1987), but the grassland sector has been greatly modified by agriculture and human settlement. Since the assessment of the Southern Ground-Hornbill’s status as ‘vulnerable’in the latest Red Data Book (Barnes 2000), it has been suggested that populations in South Africa have declined to a point where its true status is ‘endangered’but this revision was not accepted by IUCN (AC Kemp, pers. comm.). The recent initiative by the Mabula-based NGO, the Ground-hornbill Research and Conservation Project, to reintroduce birds to the Eastern Cape, prompted us to examine records of sightings in this region. The main focus is the Grahamstown map square 33 S 26 E, in which the release site of the first birds—Shamwari Private Game Reserve—is situated. Our source is the published records in Diaz Diary, the newsletter of the Diaz Cross Bird Club, which has branches in Grahamstown and Kenton-on-Sea, covering the period 1978–2004 inclusive.
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Date Issued: 2007

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A history of southern African research relevant to forensic entomology

- Williams, Kirstin A, Villet, Martin H

Authors: Williams, Kirstin A , Villet, Martin H
Date: 2006
Language: English
Type: text , Article
Identifier: vital:6909 , http://hdl.handle.net/10962/d1011862
Description: Entomological forensic evidence has been used in southern Africa for decades but explicitly forensic research began in southern Africa only 26 years ago. Although applicable local research has accumulated since 1921, it is scattered in a diverse literature or unpublished. Some overseas research has also touched on local species. This review uses a historical approach to synthesize the southern African literature and to illustrate the cross-disciplinary, opportunistic nature of forensic entomology. Distinct phases of research focused on agriculture (1921-1950), medicine (1952- 1965), ecology (1968-1990) and forensics (1980-2005), but systematics spanned the entire period and tended to be ad hoc. Few scientists were involved, situated at geographically distant locations and with widely disparate research interests. The review concludes with an overview of southern African entomologists who have been involved in medico-legal investigations, and a critical evaluation of the past and future of the discipline locally.
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Date Issued: 2006

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African Coelacanth Ecosystem Programme: An overview of the conference contributions

- Ribbink, Anthony J, Roberts, Michael J

Authors: Ribbink, Anthony J , Roberts, Michael J
Date: 2006
Language: English
Type: text , Article
Identifier: vital:7127 , http://hdl.handle.net/10962/d1010637
Description: Latimeria chalumnae is the icon for the multidisciplinary, multinational African Coelacanth Ecosystem Programme (ACEP) dedicated to improving the understanding of biological and other processes that support marine life. This article provides an overview of contributions made at a conference hosted by ACEP at the end of 2003. It also reviews significant developments regarding coelacanth conservation which have taken place since the conference. Delegates at the meeting concluded that the integrated regional,ecosystem approach that had been adopted by ACEP should continue. Underwater observation and exploration, however, should be supplemented by more experimental and technical analyses in order to answer longstanding questions related to coelacanths and other organisms.
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Date Issued: 2006

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Exploitation status of infralittoral abalone (Haliotis midae) and alikreukel (Turbo sarmaticus) in the southern section of the Eastern Cape coast, South Africa

- Proudfoot, Lee-Anne, Kaehler, Sven, McGarry, Dylan K, Uppink, P A, Aereboe, Michael, Morris, K M

Authors: Proudfoot, Lee-Anne , Kaehler, Sven , McGarry, Dylan K , Uppink, P A , Aereboe, Michael , Morris, K M
Date: 2006
Language: English
Type: Article
Identifier: vital:6915 , http://hdl.handle.net/10962/d1011878
Description: Intertidal size-frequency distributions and densities for Haliotis midae and Turbo sarmaticus were examined at 10 sites experiencing varying pressure of human exploitation along the southern section of the Eastern Cape coast, South Africa. Target species' densities and maximum sizes were related both to the numbers of collectors on the shore and to indirect indicators of exploitation such as number of households in the vicinity and distance to the nearest beach access point. For both species, there was variation in density (P < 0.05) and size (P < 0.05) among sites, with densities ranging between 0.03-2.23 m^(-2) and 0.07-4.93 m^(-2) for H. midae and T. sarmaticus, respectively. Maximum sizes ranged between 49.4-153.5 mm (H. midae) and 28.3-104.4 mm (T. sarmaticus) shell length. Population parameters such as mean maximum size and total density were significantly negatively related to exploitation indicators for both species. In addition, densities of sexually mature and legal-size individuals of T. sarmaticus were significantly negatively related to the number of households. However, only for H. midae were densities of subadults significantly negatively related to the number of collectors, suggesting that reproduction of abalone may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tends to be localized near population centres, whereas H. midae is collected over a larger range of sites. Overall, T. sarmaticus is less affected by exploitation than H. midae.
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Date Issued: 2006

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Floral resources of Apis mellifera capensis in the fynbos biome in the Eastern Cape Province, South Africa

- Addi, A, Phillipson, P, Hepburn, H Randall

Authors: Addi, A , Phillipson, P , Hepburn, H Randall
Date: 2006
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/451845 , vital:75081 , https://hdl.handle.net/10520/EJC32660
Description: The plant species utilized by Cape honeybees, Apis mellifera capensis, as primary nectar and pollen sources were studied in the Eastern Cape Province in an area where fynbos vegetation mingles with grassland communities. From direct field observations and analyses of pollen loads collected by foragers, 54 plant species were identified as nectar and pollen sources. Of 37 endemic and exotic pollen source plants, Metalasia muricata, Eucalyptus grandis, E. camadulensis, Erica chamissonis, Helichrysum odoratissimum, H. anomalum, Crassula cultrata and Acacia longifolia were dominant species.
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Date Issued: 2006

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The relationship between human exploitation pressure and condition of mussel populations along the south coast of South Africa

- Rius, Marc, Kaehler, Sven, McQuaid, Christopher D

Authors: Rius, Marc , Kaehler, Sven , McQuaid, Christopher D
Date: 2006
Language: English
Type: Article
Identifier: vital:6913 , http://hdl.handle.net/10962/d1011876
Description: Human exploitation of intertidal organisms in South Africa is an ancient activity based principally on mussels. We studied mussel populations and patterns of exploitation along a 160-km stretch of the south coast. Photographs (100 per site) were taken of the intertidal rocks at each of 14 sites, covering a range of exploitation intensities. Percentage cover was negatively correlated with number of mussel patches and positively correlated with mean shell width. PCA analysis identified groups of sites: a) accessible and unprotected sites: low cover, small mussels, patchy distribution; b) inaccessible sites and sites next to, or within, nature reserves: high percentage cover, large animals, less patchy distributions. Affluent coastal settlements also seem to confer protection against harvesting. Harvester distribution was examined by aerial surveys and combined with information on distance to the nearest beach access point and number of households within 7 km for each site. Sites within reserves and inaccessible sites had low densities of collectors, whereas sites near urban areas and in the Ciskei had the highest densities. All correlations between indicators of human exploitation and condition of mussel populations were non-significant. However, number of collectors showed positive trends with number of patches and negative trends for the two other variables. The results indicate much lower levels of exploitation than in the neighouring Transkei region, and suggest a high degree of background variability in mussel population structure.
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Date Issued: 2006

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Age, growth and reproduction of largemouth bass, Micropterus salmoides, in Lake Manyame, Zimbabwe

- Beamish, C A, Booth, Anthony J, Deacon, N

Authors: Beamish, C A , Booth, Anthony J , Deacon, N
Date: 2005
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/446770 , vital:74559 , https://doi.org/10.1080/15627020.2005.11407310
Description: A total of 478 largemouth bass, Micropterus salmoides (Lacépède, 1802), was sampled between September 1997 and July 2001 using hook-and-line in Lake Manyame, a water supply reservoir situated outside Harare, Zimbabwe. Male fish dominated the samples, possibly an effect of aggressive behaviour towards the sampling gear used. Ages, determined from sectioned sagittal otoliths, ranged from one to nine years with 94% of the sample being between one and four years of age. An annulus was deposited in late-winter/early spring. Female fish, despite being the largest fish sampled, were found to grow at a significantly slower rate than males. Growth was modelled with the von Bertalanffy model as L(t)=37.22(1–exp(–0.66t)) cm SL for males, and L(t) = 48.16(1–exp(–0.41t)) cm SL for females. All fish matured after one year, thereafter they spawned over a four-month period between July and October. Reproductive activity peaked in August. Largemouth bass has successfully colonized freshwater bodies in southern Africa where it has been introduced, causing significant ecological damage to the indigenous ichthyofauna. Given its ability to grow to a large size, and live to an old age and to breed successfully, further introductions should be viewed with extreme caution.
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Date Issued: 2005

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Monitoring the oceanic flow between Africa and Antarctica: report of the first Good Hope cruise

- Ansorge, Isabelle J, Speich, S, Lutjeharms, Johan R E, Goni, G J, Rautenbach, C J de W, Froneman, P William, Rouault, M, Garzoli, S

Authors: Ansorge, Isabelle J , Speich, S , Lutjeharms, Johan R E , Goni, G J , Rautenbach, C J de W , Froneman, P William , Rouault, M , Garzoli, S
Date: 2005
Language: English
Type: Article
Identifier: vital:6832 , http://hdl.handle.net/10962/d1007568
Description: The Southern Ocean plays a major role in the global oceanic circulation, as a component of the Meridional Overturning Circulation, and it is postulated that it has a great influence on present-day climate. However, our understanding of its complex three-dimensional dynamics and of the impact of its variability on the climate system is rudimentary. The newly constituted, international GoodHope research venture aims to address this knowledge gap by establishing a programme of regular observations across the Southern Ocean between the African and Antarctic continents. The objectives of this programme are fivefold: (1) to improve understanding of Indo-Atlantic inter-ocean exchanges and their impact on the global thermohaline circulation and thus on global climate change; (2) to understand in more detail the influence these exchanges have on the climate variability of the southern African subcontinent; (3) to monitor the variability of the main Southern Ocean frontal systems associated with the Antarctic Circumpolar Current; (4) to study air-sea exchanges and their role on the global heat budget, with particular emphasis on the intense exchanges occurring within the Agulhas Retroflection region south of South Africa, and (5) to examine the role of major frontal systems as areas of elevated biological activity and as biogeographical barriers to the distribution of plankton. We present here preliminary results on the physical and biological structure of the frontal systems using the first GoodHope transect that was completed during February-March 2004.
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Date Issued: 2005

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Multivariate analysis of honeybees, Apis mellifera Linnaeus (Hymenoptera: Apidae) of the northeastern and southern regions of Algeria.

- Barour, C, Tahar, A, Radloff, Sarah E, Hepburn, H Randall

Authors: Barour, C , Tahar, A , Radloff, Sarah E , Hepburn, H Randall
Date: 2005
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/451976 , vital:75092 , https://hdl.handle.net/10520/EJC32628
Description: Morphometric characters of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in the northeastern and southern regions (ecological-climatological zones) of Algeria, from 36°55' to 32°25'N and 3°39' to 8°22'E. Three morphoclusters were identified by using principal components and linear discriminant analyses. The bees are identified as Apis mellifera intermissa Buttel-Reepen.
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Date Issued: 2005

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Wireless communication for previously disadvantaged secondary schools in Grahamstown, South Africa.

- Brandt, Ingrid, Terzoli, Alfredo, Hodgkinson-Williams, Cheryl

Authors: Brandt, Ingrid , Terzoli, Alfredo , Hodgkinson-Williams, Cheryl
Date: 2005
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/427615 , vital:72451 , https://citeseerx.ist.psu.edu/document?repid=rep1andtype=pdfanddoi=2520d49f684e821c84350ae8c504572f35186d2f
Description: With an alarmingly low teledensity in South Africa, less than 5% in some rural areas, and not much hope of further wired infrastructure, as the costs incurred are high compared to potential revenue, wireless connec-tivity could be a great asset and service in South Africa. This paper looks at how wireless communication technologies, 802.11, WiMAX and VSAT, can be used to allow broadband connectivity of schools to the Internet, with special reference to experimental work that is being done in Grahamstown schools.
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Date Issued: 2005

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Evidence for Archaean lamprophyre from the Kaapvaal Craton, South Africa

- Prevec, S A, Anhaeusser, C R, Poujol, M

Authors: Prevec, S A , Anhaeusser, C R , Poujol, M
Date: 2004
Language: English
Type: Article
Identifier: vital:6739 , http://hdl.handle.net/10962/d1007555
Description: A suite of mafic dykes occurs as a late component in a wellcharacterized trondhjemite–tonalite–diorite–granodiorite assemblage in the Johannesburg Dome of the central Kaapvaal Craton, southern Africa. The dykes have been subdivided into two sets, based on their orientation, and major and trace element geochemistry. Set 1 dykes are characterized by elevated SiO2, Al2O3 and TiO2, and particularly by enriched LILE and HSFE (e.g. Zr > 200 ppm, Nb > 20 ppm, Ba > 300 ppm), higher than in any of the accompanying felsic rocks. REE and trace element values for Set 1 dykes are similar to those for calc-alkaline lamprophyres. The Set 2 dykes have similar trace element distributions, but are significantly less enriched in general, and are broadly tholeiitic in composition, with enriched MgO (>11 wt. percentage) indicative of an olivine–phyric tholeiitic basaltic protolith. Field relationships and available U–Pb zircon geochronology indicate that the dykes are contemporaneous with components of the trondhjemitic host rocks, and with late granodiorites. The geochemical, geochronological and field petrological setting indicates partial melting of basaltic and eclogitic lithosphere at c. 3120 Myr ago in the basal Kaapvaal Craton, and subsequent emplacement into pre-existing c. 3430 Myr tonalitic to dioritic crust.
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Date Issued: 2004

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In situ feeding rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, in a temperate, temporarily open/closed Eastern Cape estuary

- Froneman, P William

Authors: Froneman, P William
Date: 2004
Language: English
Type: text , Article
Identifier: vital:6901 , http://hdl.handle.net/10962/d1011754
Description: Size-fractionated chlorophyll-a (chl-a) concentrations and the in situ grazing rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, were assessed seasonally at the temporarily open/closed Kasouga estuary situated along the southeast coast of southern Africa. Total integrated chl-a concentration ranged between 1.17 and 12.18 mg chl-a m^(–3) and was always dominated by small phytoplankton cells (<20 μm), which comprised up to 86% (range 64–86%) of the total pigment. Total zooplankton abundance ranged between 2676 and 62 043 individuals m^(–3). These copepods numerically dominated the zooplankton counts, accounting for between 79% and 91% of the total. Gut pigment concentrations of the two species at night were significantly higher than the daytime values (P<0.05 in all cases). The observed pattern could be related to the marked diurnal vertical migration patterns exhibited by the copepods. Gut evacuation rates of P. hessei during the study ranged between 0.29 and 0.77 h^(–1) and between 0.39 and 0.58 h^(–1) for A. longipatella. The rate of gut pigment destruction for P. hessei and A. longipatella ranged between 55% and 81% and between 88% and 92% of the total chl-a ingested, respectively. The combined grazing impact of the two copepods ranged between 0.65 and 4.37 mg chl-a m^(–3), or between 4.3% and 35.9% of the available chl-a in the water column. Variations in the grazing activity of the two species could be attributed largely to seasonality in water temperature and shifts in the phytoplankton community structure and zooplankton abundance.
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Date Issued: 2004

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