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SHORT-TERM IMPACTS OF FORMULATIONS OF BACILLUS THURINGIENSIS VAR. ISRAELENSIS DE BARJAC AND THE ORGANOPHOSPHATE TEMEPHOS, USED IN BLACKFLY (DIPTERA: SIMULIIDAE) CONTROL, ON RHEOPHILIC BENTHIC MACROINVERTEBRATES IN THE MIDDLE ORANGE RIVER, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: R.W. Palmer --- Department of Water Affairs and Forestry, South AfricaThe impacts of larvicides used in the control of blackflies (Diptera: Simuliidae) on macroinvertebrates in the stones-in-current biotope were assessed during 8 field trials in the middle Orange River, South Africa. Two Bacillus thuringiensis var. israelensis (B.t.i.) products (VectobacR 12AS... -
DETRIMENTAL EFFECTS OF FENTHION (QUELETOX® UL), USED TO CONTROL RED-BILLED QUELEA (QUELEA QUELEA), ON RHEOPHILIC BENTHIC MACROINVERTEBRATES IN THE ORANGE RIVER
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: R.W. Palmer --- Department of Water Affairs and Forestry, South AfricaThe relative abundance of rheophilic macroinvertebrates in the Orange River was assessed before and 15 hrs after two aerial applications of fenthion (QUELETOX® UL) above roosting sites of the red-billed quelea (Quelea quelea). The first treatment had no detectable effect... -
IMPACTS OF REPEATED APPLICATIONS OF BACILLUS THURINGIENSIS VAR. ISRAELENSIS DE BARJAC AND TEMEPHOS, USED IN BLACKFLY (DIPTERA: SIMULIIDAE) CONTROL, ON MACROINVERTEBRATES IN THE MIDDLE ORANGE RIVER, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: R.W. Palmer --- Department of Water Affairs and Forestry, South Africa A.R. Palmer --- , South AfricaThe impacts of five consecutive treatments of blackfly larvicides on macroinvertebrates in the middle Orange River were assessed. The abundance of the midge Xenochironomus sp. and the limpet Burnupia sp. was lower at sites treated with Bacillus thuringiensis var. israelensis... -
The pollution status of Lake Nakuru, Kenya: heavy metals and pesticide residues, 1999/2000
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: WJ Mavura --- Department of Chemistry, Kenya PT Wangila --- Department of Chemistry, KenyaThis study was carried out from April 1999 to May 2000 to investigate the extent of pollution of Lake Nakuru. Water, sediment, fish and algae collected from the lake and its feeder rivers during the dry and rainy seasons were... -
Accumulation of hepatic Hsp70 and plasma cortisol in Oreochromis mossambicus following sublethal metal and DDT exposure
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SS Mlambo --- Centre for Aquatic Research, Zoology Department, South Africa JHJ van Vuren --- Centre for Aquatic Research, Zoology Department, South Africa R Basson --- Centre for Aquatic Research, Zoology Department, South Africa B Grant --- Centre for Aquatic Research, Zoology Department, South AfricaHeat shock response in Oreochromis mossambicus livers was measured, using antibodies specific to Hsp70 family members, by an immunoblotting protocol. The hepatic isoforms Hsp70, Hsp74 and Hsp76 were identified and quantified from copper exposures. Long-term DDT exposure did not result... -
Pesticides in South African fresh waters
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: TM Ansara-Ross --- Centre for Aquatic Research, Department of Zoology, South Africa V Wepener --- Centre for Aquatic Research, Department of Zoology, South Africa PJ van den Brink --- Department of Aquatic Ecology and Water Quality Management, The Netherlands MJ Ross --- Centre for Aquatic Research, Department of Zoology, South AfricaPublic concern has recently escalated over pesticide contamination of South African aquatic ecosystems. This review of published literature on the occurrence of pesticides within South African freshwater systems indicates that fewer than 50 studies of selected pesticides have been undertaken,... -
Toxicity of the chlorpyrifos-based pesticide Termifos®: effects on behaviour and biochemical and haematological parameters of African catfish Clarias gariepinus
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CD Nwani --- Department of Zoology and Environmental Biology, Nigeria DO Ugwu --- Department of Zoology and Environmental Biology, Nigeria OC Okeke --- Department of Zoology and Environmental Biology, Nigeria GC Onyishi --- Department of Zoology and Environmental Biology, Nigeria FN Ekeh --- Department of Zoology and Environmental Biology, Nigeria C Atama --- Department of Zoology and Environmental Biology, Nigeria LO Eneje --- Department of Applied Microbiology and Brewing, NigeriaThe present study, conducted in 2012, determined the toxicity of the chlorpyrifos-based pesticide Termifos® and its effects on behaviour and biochemical and haematological parameters in juvenile African catfish Clarias gariepinus. The 96 h LC50, estimated by probit analysis in a... -
Alternative approaches to Red-billed Quelea Quelea quelea management: mass-capture for food
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Clive CH Elliott --- Blue Barn House, South Leigh, UK Boaz N Mtobesya --- Plant Health Services, Tanzania Robert A Cheke --- Natural Resources Institute, UKOrganophosphate pesticide spraying or the deployment of explosives as standard practices for controlling quelea breeding colonies or roosts that threaten small-grain crops in Africa have negative side-effects on non-target birds and on the environment. Mass-capture techniques were tested as an... -
Responses of the African catfish Clarias gariepinus to long-term exposure to glyphosate- and paraquat-based herbicides
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: OI Ayanda --- Department of Biological Sciences, Nigeria SJ Oniye --- Department of Biological Sciences, Nigeria JA Auta --- Department of Biological Sciences, Nigeria VO Ajibola --- Department of Chemistry, Nigeria OA Bello --- Department of Biological Sciences, NigeriaDirect and indirect contamination of the aquatic environment by pesticides results in a decrease in fish productivity and may elevate concentrations of undesirable chemicals in edible fish tissues. The effects of long-term exposure of Clarias gariepinus juveniles to sublethal concentrations... -
Bioaccumulation and distribution of organochlorine residues across the food web in Lagos Lagoon, Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B Akinsanya --- Department of Zoology, Nigeria R Alani --- Department of Chemistry, Nigeria UD Ukwa --- Department of Zoology, Nigeria F Bamidele --- Department of Zoology, Nigeria JK Saliu --- Department of Zoology, NigeriaEighteen organochlorine pesticide (OCP) residues were measured in the water, sediment, plankton, benthic invertebrates and fish in various sections of the Lagos Lagoon in 2014 to investigate their bioaccumulation and distribution in the food web. The analysis was done using... -
Histological assessment of selected tissues in tigerfish (Hydrocynus vittatus Castelnau, 1861) from the Sanyati Basin, Lake Kariba, Zimbabwe: a DDT-sprayed area
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: N Mabika --- Department of Zoology, South Africa M Barson --- Department of Zoology, South Africa C van Dyk --- Department of Zoology, South Africa A Avenant-Oldewage --- Department of Zoology, South AfricaA pilot investigation was conducted in 2014 in the Sanyati Basin of Lake Kariba to ascertain whether long-term DDT spraying in the Kariba catchment had a negative effect on fish health. The aim was to assess the health of tigerfish,... -
Health and chemical burdens of fish species from polluted and hyper-eutrophic freshwater ecosystems in South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GM Wagenaar --- Department of Zoology, South Africa IEJ Barnhoorn --- Department of Zoology, South AfricaThree aquatic ecosystems in South Africa, the Hartbeespoort, Klipvoor and Bospoort Dams, are classified as hyper-eutrophic, because of high nutrient loads and chemical pollution. Water and two fish species, Clarias gariepinus and Cyprinus carpio, were collected from these dams to... -
Heavy metal concentrations in water and sediment of the Steelpoort River, Olifants River System, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Addo-Bediako --- Department of Biodiversity, South Africa K Matlou --- Department of Biodiversity, South Africa E Makushu --- Department of Biodiversity, South AfricaSteelpoort River has been adversely affected by human activities in the catchment. Water and sediment quality of the river was assessed in 2015. The concentrations of some of the metals in water were found to be high and exceeded the... -
Seed powder extract of physic nut (Jatropha curcas) as a biopesticide for weevils (Callosobruchus maculatus) in stored cowpea (Vigna unguiculata)
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: F. O. Ifeanyieze --- University of Nigeria, Nigeria H. I. Ameh --- University of Nigeria, Nigeria T. E. Ejiofor --- University of Nigeria, Nigeria M. E. Ikehi --- University of Nigeria, Nigeria F. M. Onu --- University of Nigeria, NigeriaThe study explored the effectiveness of physic nut (Jatropha curcas) in the control of cowpea weevils (Callosobruchus maculatus). The repellence, mortality rates and progeny emergence of weevils were observed, as well as germination viability of the treated cowpea seeds. The... -
Residue loads in amphibians used as biomarkers of pesticide levels entering food chains in sub‐Saharan Africa
Item type: Journal Article • Journal: The Journal of the Herpetological Association of Africa • Authors: MichaelR.K. Lambert --- University of Greenwich, United KingdomResidues accumulate rapidly in amphibians to reach lethal levels. During previous years in Zimbabwe, total DDT residues from general agricultural contamination were at 3.90 ppm wet weight in Bufo gutturalis and 1.50 ppm in Ptychadena anchietae. Dieldrin residues in the... -
Comparison of the acute toxicity and behavioural effects of two pyrethroids on African catfish Clarias gariepinus fingerlings
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: EO Ogueji --- Alex Ekwueme Federal University, Nigeria JJ Ekpenyong --- Alex Ekwueme Federal University, Nigeria GU Amana --- Kogi State University, Nigeria EB Tabi --- Alex Ekwueme Federal University, Nigeria IB Okey --- Cross River University of Technology, Nigeria MO Olaolu --- Alex Ekwueme Federal University, Nigeria JN Nwakpa --- Ebonyi State University, NigeriaTwo of the most-commonly used pyrethroid insecticides were subjected to static bioassays to determine their acute toxicity to Clarias gariepinus fingerlings, followed by comparisons of their impact on mortality and behavioural changes in the fish. The LC50 values for deltamethrin... -
Occurrence of contaminants of emerging concern in the uMhlathuze and uThukela river systems, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LR Nsibande --- University of Zululand, South Africa RF Lehutso --- Water Centre, Council for Scientific and Industrial Research, South Africa M Thwala --- Academy of Science of South Africa, South Africa HMM Mzimela --- University of Zululand, South Africa M Seopela --- University of Johannesburg, South Africa NF Masikane --- University of Zululand, South AfricaContaminants of emerging concern (CECs), which include inorganic substances, exhibit potential adverse effects on aquatic life even though they commonly occur at very low concentrations in aquatic resources. The lack of data available about the risk of CECs to the... -
Sublethal agrochemical residues in South African birds, 1969–2024
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Lorinda A Hart --- BirdLife South Africa, South Africa Linda van den Heever --- BirdLife South Africa, South Africa Jan-Dieter Ludwigs --- , GermanyAvian species serve as a barometer of ecosystem health and have been used to determine the presence of chemicals in the South African environment. We conducted a literature review to determine which sublethal agrochemical active ingredient residues have been tested...