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ASPECTS OF THE BIOLOGY OF TILAPIA RENDALLI IN THE DOORNDRAAI DAM TRANSVAAL
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: G.R. Batchelor --- Division of Nature Conservation, South AfricaScale studies indicated that the annulus is a reliable year mark. A linear relationship existed between scale radius and body growth enabling back calculations to be made. The growth rate of males in Doorndraai Dam were similar to findings in... -
BEHAVIOUR OF A RADIO-TAGGED TILAPIA RENDALLI BOULENGER IN LAKE NGEZI, ZIMBABWE
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: CharlesH. Hocutt --- Horn Point Environmental Laboratories, United States of AmericaThe behaviour of a single specimen of Tilapia rendalli Boulenger was observed June through October 1986 in Lake Ngezi, Zimbabwe, by the use of a surgically-implanted radiotransmitter. The individual displayed a distinct homing response on two occasions, returning to the... -
The effects of lead, water hardness and pH on oxygen consumption, plas- ma chlorides and bioaccumulation in the freshwater fish Tilapia sparrmanii
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: WJ van Aardt LCR VenterClosed system respirometry was performed on captive juvenile Tilapia sparrmanii exposed for 96 hours to a range of Pb-acetate concentrations in hard and soft water to determine the effect of Pb in relation to water hardness and pH. For hard... -
Biomagnification of mercury in fish from Thruston Bay, Napoleon Gulf, Lake Victoria (East Africa)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LindaM Campbell JS Balirwa DG Dixon RE HeckyTotal mercury concentrations (THg) were measured in fish from Thruston Bay, Napoleon Gulf in northern Lake Victoria between 1998 and 2000. Total Hg concentrations in Lates niloticus (Nile perch) and Oreochromis niloticus (Nile tilapia) ranged from 10.6 to 77.5ng g–1... -
Fish migrations in two seasonal streams in Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Brian Gratwicke BrianE MarshallFish migrations into the streams of seasonally-flooded depressions (or dambos) that cover the central plateaus of Africa are a well-known phenomenon to scientists and lay people alike. However, the factors causing seasonal migrations are poorly understood and most scientific references... -
Comparative analysis of the aquaculture potential of hybrid Tilapia zillii (male) × T. guineensis (female) (Teleostei: Cichlidae) in floating cages, cement tanks and earth ponds
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CélineSK Nobah Tidiani Koné Valentin N'Douba Jos Snoeks Gouli Gooré Bi EssetchiP KouamélanThe effect of three rearing systems, floating cages, cement tanks and earth ponds, on the growth rate, feeding efficiency and mortality rates of hybrid tilapia — Tilapia zillii (male) × T. guineensis (female) — was evaluated for 233 days. Fish... -
Fish distributions in the Rondegat River, Cape Floristic Region, South Africa, and the immediate impact of rotenone treatment in an invaded reach
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: OLF Weyl --- , South Africa BR Ellender --- Department of Ichthyology and Fisheries Science, South Africa DJ Woodford --- , South Africa MS Jordaan --- , South AfricaAlien fishes are considered the most serious threat to native headwater stream fishes in South Africa. A 4 km reach of the Rondegat River is the first section of a South African river to be rehabilitated through the attempted removal... -
Characterisation of potential aquaculture pond effluents, and physico-chemical and microbial assessment of effluent-receiving waters in central Ghana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: YB Ansah --- Department of Fish and Wildlife Conservation, USA EA Frimpong --- Department of Fish and Wildlife Conservation, USA S Amisah --- Department of Fisheries and Watershed Management, GhanaAn understanding of specific aquaculture systems and the impacts of their management practices leads to sound and cost-effective policies to protect the aquatic environment. Water samples were collected in 2009 from fish ponds, streams that receive effluents directly from ponds... -
Effect of feeding frequency and feeding rate on growth of Oreochromis mossambicus (Teleostei: Cichlidae) fry
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RW Luthada --- Department of Zoology, South Africa HL Jerling --- Department of Zoology, South AfricaThe effect of feeding frequency and feeding rate on growth of Oreochromis mossambicus fry was investigated over 30 d under temperature- and light-cycle-controlled conditions on the University of Zululand campus, South Africa, in October and November 2009. Weight gain, specific... -
An interdisciplinary method to harmonise ecology, economy and co-management: fisheries exploitation in Lake Nabugabo, Uganda
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: I Vaccaro --- Department of Anthropology and McGill School of Environment, Canada CA Chapman --- Department of Anthropology and McGill School of Environment, Canada EA Nyboer --- Department of Biology, Canada M Luke --- McGill School of Environment, Canada A Byekwaso --- National Fisheries Resources Research Institute, Uganda C Morgan --- McGill School of Environment, Canada D Mbabazi --- National Fisheries Resources Research Institute, Uganda D Twinomugisha --- Makerere University Biological Field Station, Uganda LJ Chapman --- Department of Biology, CanadaCollective action theory predicts that natural resource management at a local level has a higher probability of success if territoriality and jurisdiction of the managerial institution are in synchrony with mobility and territoriality of the resource and exploitation patterns of... -
Simultaneous extraction of chitin and astaxanthin from waste of lobsters Jasus lalandii, and use of astaxanthin as an aquacultural feed additive
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Auerswald G GädeThis work investigates simple methods for simultaneous extraction of astaxanthin and chitin from industrial waste of the South African West Coast rock lobster Jasus lalandii. Removal of proteins from waste is the critical step to yield intact chitin and astaxanthin... -
Growth rates of alien Oreochromis niloticus and indigenous Oreochromis mortimeri in Lake Kariba, Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PC Chifamba --- Department of Biological Sciences, Zimbabwe JJ Videler --- Centre for Ecological and Evolutionary Studies, The NetherlandsGrowth rates of indigenous Oreochromis mortimeri and alien Oreochromis niloticus from Lake Kariba were estimated from samples collected in 1997–2000, 2003–2005 and 2010–2011. Growth zones on scales and otoliths of O. niloticus and on the otoliths and opercula of O... -
Competition and niche partitioning in a floodplain ecosystem: a cladoceran community squeezed between fish and invertebrate predation
Item type: Journal Article • Journal: African Zoology • Authors: Markus Lindholm --- Department of Biology, Norway Dag Olav Hessen --- Department of Biology, NorwaySeasonal floodplains occasionally comprise highly productive zooplankton communities which are exposed to rapid shifts in predator regimes, also between vertebrate and invertebrate predators.We recorded the impact of two co-occurring zooplankton predators, the notonectid Anisops sardea and 0+ fish fry of... -
Invasion of a headwater stream by non-native fishes in the Swartkops River system, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Bruce R. Ellender --- Department of Ichthyology and Fisheries Science, South Africa Olaf L. F. Weyl --- South African Institute for Aquatic Biodiversity, South Africa Ernst R. Swartz --- South African Institute for Aquatic Biodiversity, South AfricaIn South Africa, fishes in headwater streams are increasingly being threatened by non-native fish invasions. These invasions originate primarily from source populations in mainstream rivers and impoundments. In the Blindekloof stream, a Swartkops River headwater tributary, the non-native Micropterus salmoides... -
Water cytotoxicity and dioxins bioaccumulation in an Egyptian delta wetland ecosystem
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: MM El-Shazly --- Department of Entomology, Faculty of Science, Egypt El Elzayat --- Department of Zoology, Faculty of Science, Egypt WA Omar --- Department of Zoology, Faculty of Science, Egypt IIA El-Sebeay --- Plant Protection Research Institute, Agricultural Research Center, Egypt YA Edmardash --- Department of Entomology, Faculty of Science, Egypt MM Soliman --- Department of Entomology, Faculty of Science, Egypt KM Abdel Rahman --- Department of Entomology, Faculty of Science, Egypt MS Ibrahim --- Department of Geography, Faculty of Arts, EgyptManzala Lake, as one of the main Egyptian wetland ecosystems, is facing risks of pollution. An in vitro cytotoxicity test using a mammalian cell line was employed to determine the toxicity of multiple pollutants in the water and Tilapia zillii... -
Record of Blue tilapia Oreochromis aureus (Steindachner, 1864) in the Eerste River catchment, Western Cape province, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SM Marr --- South African Institute for Aquatic Biodiversity, South Africa G Gouws --- South African Institute for Aquatic Biodiversity, South Africa S Avlijas --- Redpath Museum, Canada D Khosa --- South African Institute for Aquatic Biodiversity, South Africa ND Impson --- Scientific Services, South Africa M van der Westhuizen --- Conservation Services, South Africa OLF Weyl --- South African Institute for Aquatic Biodiversity, South AfricaOreochromis aureus was imported from Israel into South Africa in 1959 but data on its current status in South Africa are lacking. Genomic DNA was extracted and the COI gene amplified at the South African Institute for Aquatic Biodiversity. The... -
Morphological differentiation among populations of Sarotherodon melanotheron melanotheron Rüppell 1852 across the West African Lagoon systems (Benin, Cameroon, Nigeria, Togo)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: MO Popoola --- Department of Zoology, Nigeria FDB Schedel --- SNSB-Bavarian State Collection Zoology, Germany MA Akintoye --- Department of Zoology, NigeriaMorphometric variation among populations of Sarotherodon melanotheron melanotheron across its natural range (Mahin, epe, Lekki, Apese, Kuramo, Lagos, Iyagbe, Ologe, Badagry, Yewa – Nigeria; Be Lagoon – Togo; Idenau – Cameroon, Aheme – Benin; Portonovo – Benin) were studied to... -
The role of fish-poultry integration on fish growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AP Shoko --- Tanzania Fisheries Research Institute, Tanzania SM Limbu --- Department of Aquatic Sciences and Fisheries Technology, Tanzania HA Lamtane --- Department of Animal, Aquaculture and Range Sciences, Tanzania MA Kishe-Machumu --- Tanzania Fisheries Research Institute, Tanzania B Sekadende --- Tanzania Fisheries Research Institute, Tanzania EE Ulotu --- Tanzania Fisheries Research Institute, Tanzania JC Masanja --- Kilombero District Council, Tanzania YD Mgaya --- Department of Aquatic Sciences and Fisheries Technology, TanzaniaAquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male... -
Nevirapine in African surface waters induces liver histopathology in Oreochromis mossambicus: A laboratory exposure study
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: UMC Nibamureke --- Department of Zoology, South Africa IEJ Barnhoorn --- Department of Zoology, South Africa GM Wagenaar --- Department of Zoology, South AfricaNevirapine (NVP) is one of the HIV antiretrovirals detected recurrently in African surface waters. Liver side effects in humans were reported. Because the effects on fish are unknown, this study investigated the potential effects of NVP on selected biometric indices... -
Relative growth of invasive and indigenous tilapiine cichlid fish in Tanzania
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SJ Bradbeer --- , United Kingdom BP Ngatunga --- , Tanzania GF Turner --- , United Kingdom MJ Genner --- , United KingdomNon-native species have been widely distributed across Africa for the enhancement of capture fisheries, but it can be unclear what benefits in terms of fisheries production the non-native species bring, compared with native species. Here we compared the relative growth... -
Cadmium and lead levels in three freshwater fish species from the Zambezi region, Namibia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: O Madzingira --- , Namibia LZ Lifumbela --- , Namibia E Kandiwa --- , Namibia L Kandjengo --- , Namibia B Mushonga --- , NamibiaMuscle tissue from three-spotted tilapia (Oreochromis andersonii) (n = 11), sharp tooth catfish (Clarias gariepinus) (n = 14) and tigerfish (Hydrocynus vittatus) (n = 12) were sampled from a market in the Zambezi region, Namibia in June 2018 and analysed... -
Lamproglena monodi Capart, 1944 infecting Oreochromis niloticus (Linnaeus, 1758): additional information on infection, morphology and genetic data
Item type: Journal Article • Journal: African Zoology • Authors: Nehemiah Mogoi Rindoria --- , South Africa Quinton Marco Dos Santos --- , South Africa Shimaa E Ali --- , Egypt Mohammed Hasan Ibraheem --- , Egypt Annemariè Avenant-Oldewage --- , South AfricaLamproglena monodi Capart, 1944 adult females were first described from the Democratic Republic of the Congo and have been redescribed seven times from different cichlid species in Egypt, Burkina Faso and Brazil, all showing morphological variation. The adult male was... -
Biological and life-history parameters for Labeo rosae Steindachner, 1894 and Oreochromis mossambicus (Peters, 1852) from Flag Boshielo Dam, Olifants River, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HA Hlungwani --- University of Limpopo, South Africa SM Marr --- University of Limpopo, South Africa OLF Weyl --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa JR Sara --- University of Limpopo, South AfricaInland fisheries contribute towards food security for rural communities living close to large aquatic systems. However, sustainable inland fisheries rely on accurate biological information for the target species at the proposed fishery location. In this study, the biological information for... -
Status of diversity, abundance and seasonal variations of gill net catches of cichlids in Lake Bosumtwi, Ghana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: A Asase --- University of Ghana, Ghana TL Lauridsen --- Aarhus University, Denmark PO Sanful --- University of Energy and Natural Resources, Ghana EEK Quansah --- University of Ghana, Ghana FKE Nunoo --- University of Ghana, GhanaThe cichlids in Lake Bosumtwi are under increasing pressure with a recent build-up in local fishing pressure. This study was conducted to assess the status and seasonal catch rates of fish species using gillnets over a two-year period. Four species...