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Pathotypes of Puccinia graminis f. sp. tritici detected in South Africa during 1991–1997
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W. H.P. Boshoff --- , Republic of South Africa B.D. van Niekerk --- , Republic of South Africa Z.A. Pretorius --- Department of Plant Pathology, Republic of South AfricaA stem rust survey is conducted annually in the major bread wheat and triticale producing areas of South Africa to monitor pathogenic variability in Puccinia graminis f. sp. tritici. During 1991 to 1996 the incidence of stem rust on susceptible... -
Precision in systematic trawl surveys as assessed from replicate sampling by parallel trawling off Namibia
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: T. Strømme T. IilendeFollowing independence of Namibia in 1990, abundance of that country's hake stocks was monitored by trawl surveys conducted by the Norwegian F.R.V. Dr Fridtjof Nansen using a systematic survey design. Precision from such designs is considered to be better than... -
Towards a catchability constant for trawl surveys of Namibian hake
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: I. Huse T. Iilende T. StrømmeA trawl catches only a portion of the fish in its path. The term catchability therefore refers to the fraction of the available fish caught. A method was developed and tested to establish catchability constants for trawl surveys of Namibian... -
Evaluation of a class of possible simple interim management procedures for the Namibian hake fishery
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: D. S. Butterworth H. F. GeromontDuring 1997, considerable scientific differences arose about the status of the Namibian hake (Merluccius capensis and M. paradoxus) resource, and as to whether the hake Total Allowable Catch (TAC) should be substantially decreased or increased. These differences revolved primarily around... -
A review of orange roughy Hoplostethus atlanticus fisheries, estimation methods, biology and stock structure
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: T. A. BranchOrange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at... -
Dynamics of the pelagic component of Namibian hake stocks
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: T. Iilende T. Strømme E. JohnsenA study was undertaken to investigate the spatial, diurnal and interannual dynamics of the pelagic component of Namibian hake stocks. Data were derived from trawl surveys conducted on board the R.V. Dr Fridtjof Nansen during the period 1991–1999. In addition... -
Catch and effort of the shore and skiboat linefisheries along the South African Eastern Cape Coast
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: S. L. Brouwer C. D. BuxtonAn assessment of catch and effort in the Eastern Cape shore and skiboat linefisheries was undertaken between 1994 and 1996 by means of roving creel and access point surveys. Catch-and-effort data were obtained from direct observation of 3 273 shore-fishers,... -
Research note: Grazing‐index method procedures of vegetation surveys
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: P.C.V. du Toit --- , Republic of South AfricaIn the past, veld condition in the Karoo was assessed using the ecological index method. This recently changed to the grazing‐index method on account of the differently estimated grazing‐index values being used. The principles governing the method of survey remain... -
The influence of peers and other significant persons on sexuality and condom-use among young adults in northern Tanzania
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Bernard Njau Sabina Mtweve Longin Barongo Rachel Manongi Juliet Chugulu Marcelina Msuya Stella Mwampeta Bertha Kiwale Joseph Lekule Hector JalipaSexual behaviour change remains a primary goal of HIV prevention efforts globally. It is a complex issue influenced by numerous unpredictable variables such as individual desires, social and cultural relationships, and environmental and economic dynamics. This study in northern Tanzania... -
Misconceptions about HIV prevention and transmission in Botswana
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Gobopamang LetamoMisconceptions about how HIV can be transmitted or prevented often prevent individuals from making informed choices and taking appropriate action. The purpose of the research was to explore the socio-demographic and behavioural factors in Botswana that are associated with misconceptions... -
The protective effect of male circumcision on HIV infection in a sample of Kenyan men
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: YanyiK Djamba LaToyaS DavisThis article examines the association between male circumcision and HIV infection in a national sample. The analysis is based on the 2003 Kenya Demographic and Health Survey (KDHS), a nationally representative household-based population survey of adults, in which male respondents... -
Fertility desire and family-planning demand among HIV-positive women and men undergoing antiretroviral treatment in Addis Ababa, Ethiopia
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Wossenyelesh Tamene Mesganaw FantahunLittle information exists about desire to have children and family-planning use among HIV-positive individuals and how this may vary according to individual, social, health and demographic characteristics, especially in developing countries. To assess these topics in Ethiopia, a facility-based cross-sectional... -
Contextual factors associated with treatment-seeking and higher-risk sexual behaviour in Botswana among men with symptoms of sexually transmitted infections
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Tabitha LangeniThis study investigates contextual factors associated with treatment-seeking behaviour and higher-risk sexual conduct of men symptomatic of sexually transmitted infections (STIs) in Botswana. Data were drawn from a randomly selected, nationally representative sample of 8 222 men, aged 15–64 years,... -
Understanding self-appraisal of HIV-infection risk among young adults in Nigeria: evidence from a national survey
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Samson Babatunde Adebayo --- , Nigeria Jennifer Anyanti --- , Nigeria Augustine Ankomah --- , Kenya Godpower Omoregie --- , Nigeria Fatima Mamman-Daura --- , NigeriaA major component of HIV prevention is to encourage individuals to appreciate their personal risk of contracting the virus with the aim of encouraging them to take steps to reduce the risks. This article addresses the accuracy of an individual's... -
The influence of antiretroviral treatment on willingness to test: a qualitative study in rural KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Zipho Phakathi --- , South Africa Heidi Van Rooyen --- , South Africa Katherine Fritz --- , United States Linda Richter --- , South AfricaPrevious quantitative studies suggest a mutually reinforcing relationship between HIV counselling and testing (HCT) and antiretroviral treatment (ART). HCT is the entry into ART, and access to ART appears to increase HIV-testing uptake in settings with historically low uptake. Adopting... -
Depression underdiagnosis and the effects on quality of life in outpatients with HIV at a Nigerian university teaching hospital
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Victor Obiajulu Olisah --- Department of Psychiatry, Nigeria Olusegun Baiyewu --- Department of Psychiatry, Nigeria Taiwo Lateef Sheikh --- Department of Psychiatry, NigeriaThe study aimed to determine the frequency of depressive disorder in a sample of patients with HIV and its level of underdiagnosis by attending physicians. The study also explored the effect of depressive disorder on the quality of life (QOL)... -
Poverty, sexual behaviour, gender and HIV infection among young black men and women in Cape Town, South Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Nicoli Nattrass --- Centre for Social Science Research (CSSR), South Africa Brendan Maughan-Brown --- Southern Africa Labour and Development Research Unit, South Africa Jeremy Seekings --- Centre for Social Science Research (CSSR), South Africa Alan Whiteside --- Health Economics and HIV/AIDS Research Division (HEARD), South AfricaThis article contributes methodologically and substantively to the debate over the importance of poverty, sexual behaviour and circumcision in relation to HIV infection, using panel data on young black men and women in Cape Town, South Africa. Methodological challenges included... -
Correlates of HIV-status awareness among adults in Nairobi slum areas
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Remare Renner Ettarh --- , Kenya James Kimani --- , Kenya Catherine Kyobutungi --- , Kenya Frederick Wekesah --- , KenyaThe prevalence of HIV in the adult population in slum areas in Nairobi, Kenya, is higher than for residents in the city as a whole. This disparity suggests that the characteristics of slum areas may adversely influence the HIV-prevention strategies... -
Evaluation of Participation in and Management of the Transkei Shore Linefishery
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: B. Q. Mann A. M. McDonald W. H. H. Sauer T. HechtBoth roving creel and aerial surveys were used to quantify fishing effort along the former Transkei coast. A stratified random sampling procedure was used during shore patrols to assess catch and effort, and a questionnaire survey provided information on total... -
Distribution patterns of key fish species of the southern Benguela ecosystem: an approach combining fishery-dependent and fishery-independent data
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. Pecquerie L. Drapeau P. Fréon J. C. Coetzee R. W. Leslie M. H. GriffithsWithin the context of an ecosystem approach for fisheries, there is a need for quantitative information on distributions of key marine species. This information is valuable input for modelling species interactions in the southern Benguela ecosystem. In the present study,... -
An assessment of participation, catch and effort in the offshore boat-based linefishery in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SW Dunlop --- , South Africa BQ Mann --- , South AfricaThis study evaluates trends in participation, catch and effort in the KwaZulu-Natal offshore boat-based linefishery. Methods used included a random access-point survey and an associated questionnaire survey. The study was undertaken between February 2009 and April 2010. Total participation in... -
Long-term population effect of male circumcision in generalised HIV epidemics in sub-Saharan Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Michel GarenneThis paper examines the complex relationship between male circumcision and HIV prevalence and incidence in sub-Saharan African countries that have generalised epidemics. In South Africa, the mean yearly HIV incidence and an estimate of the net reproduction rate of the... -
The effectiveness of a national communication campaign using religious leaders to reduce HIV-related stigma in Ghana
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Marc Boulay Ian Tweedie Emmanuel FiagbeyThis article describes the effects of a national mass media and community-level stigma-reduction programme in Ghana, in which national and local religious leaders urged their congregations and the general public to have greater compassion for people living with HIV or... -
Employees' perceptions of the Aid-for-AIDS disease-management programme, South Africa
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Alan Rothberg Karen Van HuyssteenIt is estimated that 18–20% of South Africa's more than 5 million HIV-positive individuals are formally employed. Disease management programmes for these employees vary in scope and sophistication, with services provided by the employer, or third-party specialist disease managers, or... -
Sex differentials in the use of centres for voluntary counselling and testing for HIV in Cameroon
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Emmanuel Ngwakongnwi Hude QuanPart of the strategic response to HIV in Cameroon, West Africa, has been the institutionalisation of voluntary testing and counselling (VCT) for HIV services across the country. The study addresses the general level of awareness and use of VCT centres... -
Refined estimates of South African pelagic fish biomass from hydro-acoustic surveys: quantifying the effects of target strength, signal attenuation and receiver saturation
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JC Coetzee D Merkle CL de Moor NM Twatwa M Barange DS ButterworthThe biomass of small pelagic fish species off the coast of South Africa has been monitored since 1984 using hydro-acoustic survey techniques. These time-series of spawner biomass and recruitment estimates form the basis for management of both the South African... -
The effects of stock size and environmental variability on Cape hake recruitment in Namibia: an unsolved puzzle (a comment on Kainge et al. 2013)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J-P Roux --- Lüderitz Marine Research, Namibia MR Wilhelm --- Marine Science Institute, USAMeasuring and forecasting recruitment are central to the understanding and management of fish stocks. Kainge et al. (2013) studied the effect of spawning stock size and environmental fluctuations on the recruitment levels of the Cape hake Merluccius capensis in Namibia... -
Diel effects on bottom-trawl survey catch rates of shallow- and deep-water Cape hakes Merluccius capensis and M. paradoxus off Namibia, using solar zenith angle
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P Kainge --- National Marine Information and Research Centre (NatMIRC), Namibia K Wieland --- Section for Monitoring and Data, Institute of Aquatic Resources, Denmark J Feekings --- Section for Ecosystem based Marine Management, DenmarkDiel patterns in survey trawl catches for the Cape hakes Merluccius capensis and M. paradoxus off Namibia were studied in order to examine the effect of diel bias on catchability, and its implication for survey abundance estimation and the consistency... -
Structure and dynamics of demersal fish assemblages over three decades (1985–2012) of increasing fishing pressure in Guinea
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ML Camara --- Centre National des Science Halieutiques de Boussoura (CNSHB), Republic of Guinea B Mérigot --- Université de Montpellier, France F Leprieur --- Université de Montpellier, France JA Tomasini --- Université de Montpellier, France I Diallo --- Centre National des Science Halieutiques de Boussoura (CNSHB), Republic of Guinea M Diallo --- Centre National des Science Halieutiques de Boussoura (CNSHB), Republic of Guinea D Jouffre --- Institut de Recherche pour le Développement, SenegalIn a context of growing fishing pressures and recommendations for an ecosystem approach to fisheries, there is a need to monitor changes in fish communities over time. In this study, we analysed data from scientific trawl surveys carried out on... -
The first range-wide assessment of Saddle-billed Stork Ephippiorhynchus senegalensis distribution
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Jonah Gula --- Department of Biology, United States Floyd Weckerly --- Department of Biology, United States KS Gopi Sundar --- International Crane Foundation, United StatesThe Saddle-billed Stork Ephippiorhynchus senegalensis exemplifies a case in conservation research in which a species is assessed as Least Concern on the IUCN Red List and the resulting consideration of low conservation priority has precluded proper scientific study. As a... -
Using action cameras to estimate the abundance and habitat use of threatened fish in clear headwater streams
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B Hannweg --- , South Africa SM Marr --- , South Africa LE Bloy --- , South Africa OLF Weyl --- , South AfricaSnorkel and electrofishing surveys are the traditional baseline methods for fish surveys in clear headwater streams. However, action cameras provide a non-harmful alternative to monitor freshwater fish populations to develop informed conservation management initiatives. In this paper, estimates from photographs... -
A survey of Great-winged Petrels Pterodroma macroptera breeding at sub-Antarctic Marion Island and a revised global population estimate
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Ben J Dilley --- , South Africa David W Hedding --- , South Africa Stefan Schoombie --- , South Africa Peter G Ryan --- , South AfricaAlthough burrow-nesting petrels are the most abundant group of seabirds in the Southern Ocean, their global populations are poorly known, because most species breed on remote islands. For example, there are no accurate estimates for Great-winged Petrel Pterodroma macroptera populations... -
The trade in the endangered African Grey Parrot Psittacus erithacus and the Timneh Parrot Psittacus timneh in Algeria
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Sadek Atoussi --- , Algeria Daniel Bergin --- , United Kingdom Imane Razkallah --- , Algeria Vincent Nijman --- , United Kingdom Mouslim Bara --- , Algeria Zihad Bouslama --- , Algeria Moussa Houhamdi --- , AlgeriaThe global wildlife trade is considered one of the main threats to the conservation of a large number of imperilled species. African Grey parrots are one of the most heavily traded groups of birds, which led the International Union for... -
Importance of detailed soil surveys for Conservation Agriculture
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: JL Schoeman --- , E Verster --- , HB Booyens --- , MJ du Plessis --- ,This paper explores the role that detailed soil surveys can play in Conservation Agriculture (CA). While it is widely acknowledged that CA practices have to be adapted to local conditions, it appears as if in-field physical soil and hydrological properties,... -
Assessments of range-wide distribution of six African storks and their relationships with protected areas
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Jonah Gula --- , USA M Clay Green --- , USA Sarah Fritts --- , USA W Richard J Dean --- , South Africa KS Gopi Sundar --- , IndiaSpecies range maps provided by the IUCN and BirdLife International are recognised to sometimes mischaracterise distribution and have resulted in inaccurate status assessments. In this study we assessed distribution trends and relationships with protected area extent for six African storks,... -
Road counts reveal The Gambia’s West Coast region still has the densest population of Hooded Vultures Necrosyrtes monachus in Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Mawdo Jallow --- , The Gambia Momodou L Dibba --- , The Gambia Fagimba Camara --- , The Gambia David R Barber --- , United States Keith L Bildstein --- , United States Lindy J Thompson --- , United StatesRoad surveys are a useful tool for comparing vulture population trends. Here we present data from road surveys to count Hooded Vultures Necrosyrtes monachus in The Gambia in 2017 and 2021. In the first nationwide road survey in November 2017... -
The avifauna of Niokolo-Koba National Park, Senegal: a review of historical and recent ornithological records
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: John B Rose --- , France Oliver JL Fox --- , The Gambia Bram Piot --- , Laos Philippe Delaporte --- , FranceWe present the results of a review of the bird species historically observed in Niokolo-Koba National Park, a World Heritage Site and 913 000 ha natural protected area in southeastern Senegal. In carrying out this work we consulted both formal... -
Equity of the HIV epidemic response in 13 African countries
Item type: Journal Article • Journal: African Journal of AIDS Research • Authors: Gary Gaumer --- Brandeis University, USA V. S. Senthil Kumar --- Brandeis University, USA William Crown --- Brandeis University, USA Monica Jordan --- Brandeis University, USA Clare Hurley --- Brandeis University, USA Maya Subramanian --- Brandeis University, USA A. K. Nandakumar --- Brandeis University, USAFor over 25 years, new programs to attempt to stem the HIV epidemic have been developed in Africa by country governments as well as external donors. These programs and activities have built and operated facilities, trained clinicians, financed drugs and... -
The Africa Bird Data packages: African citizen science bird data in R
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Francisco Cervantes --- University of Cape Town, South Africa Alan TK Lee --- University of Cape Town, South Africa Dominic AW Henry --- University of Cape Town, South Africa Michael Brooks --- University of Cape Town, South Africa Vernon Visser --- University of Cape Town, South Africa Ané Cloete --- University of Cape Town, South Africa Nancy Job --- South African National Biodiversity Institute, South Africa Res Altwegg --- University of Cape Town, South AfricaThe African Bird Atlas Project (ABAP) and the Coordinated Waterbird Counts (CWAC) are the main citizen science bird monitoring programmes in southern Africa. ABAP data are collected by volunteers that compile bird lists over a grid of geographic areas known... -
A shelf-scale assessment of GLORYS and BRAN ocean reanalysis model outputs for the southern Benguela Upwelling System
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AM Kupczyk --- Fisheries and the Environment (DFFE), South Africa T Lamont --- Fisheries and the Environment (DFFE), South Africa I Halo --- Fisheries and the Environment (DFFE), South Africa CS Russo --- Fisheries and the Environment (DFFE), South Africa T Rixen --- Institute for Geology, Universität Hamburg, Germany N Lahajnar --- Institute for Geology, Universität Hamburg, GermanyThe Benguela Upwelling System, with its high variability and productivity, is challenging to monitor owing to limited in situ ocean observations. Researchers therefore often use ocean reanalysis products to simulate oceanographic conditions. We evaluated the performance of the GLORYS and...