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An assessment of the recreational fishery in the St Lucia estuarine system, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: B. Q. Mann N. C. James L. E. BeckleySt Lucia is one of the largest estuarine systems in Africa, and attracts thousands of anglers each year. Catchcard data from the National Marine Linefish System for the years 1986–1999 were analysed to determine catch composition, catch per unit effort... -
Assessment of resource availability and suitability for subsistence fishers in South Africa, with a review of resource management procedures
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: A. C. Cockcroft W. H. H. Sauer G. M. Branch B. M. Clark A. H. Dye E. RussellThe availability of resources and their suitability for subsistence and small-scale commercial fishers in South Africa were assessed and appropriate options for the management of resources recommended. Assessment of current resource utilization and recommendations for future subsistence and/or small-scale commercial... -
ZOOPLANKTON AND ENVIRONMENTAL CONDITIONS IN GROENVLEI, SOUTHERN CAPE, DURING 1976
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.J. Coetzee --- Cape Department of Nature and Environmental Conservation, South AfricaThe zooplankton and environmental conditions in Groenvlei were studied during 1976 as part of an overall ecological study of the zooplankton of the Wilderness Lakes system. The Groenvlei water was found to be well mixed and low in dissolved PO4−P,... -
ZOOPLANKTON DISTRIBUTION IN RELATION TO ENVIRONMENTAL CONDITIONS IN THE SWARTVLEI SYSTEM, SOUTHERN CAPE
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.J. Coetzee --- Cape Department of Nature and Environmental Conservation, South AfricaSwartvlei is an ectogenic meromictic coastal lake connected to the sea via an estuary which closes periodically due to the formation of a sand bar across its mouth. The inflow of high-salinity water water from the sea into the lake... -
ZOOPLANKTON AND ENVIRONMENTAL CONDITIONS IN A SOUTHERN CAPE COASTAL LAKE SYSTEM
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.J. Coetzee --- Cape Department of Nature and Environmental Conservation, South AfricaThe usually natural closing and artificial opening of the Tow River mouth to the sea have a major influence on the physico-chemical environmental conditions in the coastal lake system formed by the Tow River, Eilandvlei, Langvlei and Rondevlei, as it... -
VALUES FOR THE FIRST AND SECOND APPARENT DISSOCIATION CONSTANTS, K'1 & K'2 OF CARBONIC ACID FOR ESTUARINE AND BRACKISH WATERS AS A FUNCTION OF TEMPERATURE AND CHLORINITY
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.R. Allanson --- Institute for Freshwater Studies, Department of Zoology and Entomology, Republic of South Africa C. Duncombe Rae --- Institute for Freshwater Studies, Department of Zoology and Entomology, Republic of South Africa -
ZOOPLANKTON AND ESTUARINE RELICT (BENTHIC) FAUNA IN LAKE MZINGAZI, A FRESHWATER COASTAL LAKE OF NATAL
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: B.K. Fowles --- , South Africa C. G.M. Archibald --- , South AfricaLake Mzingazi, a natural, undisturbed freshwater coastal lake in the heart of the Richards Bay municipal area, is threatened by rapid urban and industrial growth. The previously unrecorded composition and distribution of zooplankton in the lake was studied during 1979... -
TURBIDITY AND OTHER PHYSICAL FACTORS IN NATAL ESTUARINE SYSTEMS PART 2: ESTUARINE LAKES
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.P. Cyrus --- Department of Zoology, South AfricaData on turbidity, temperature and salinity and the factors which affect them, such as wind and substratum, were collected from Natal's two estuarine Lakes. The effects of wind and substratum, were collected from Natal's two estuarine Lakes. The effects of... -
DISTRIBUTION AND ABUNDANCE OF THE BENTHOS IN THE SEDIMENTS OF LAKE CUBHU: A FRESHWATER COASTAL LAKE IN ZULULAND SOUTH AFRICA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.P. Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa T.J. Martin --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaA preliminary investigation of the macrobenthic invertebrates of the sediments of Lake Cubhu, a freshwater coastal lake near Richards Bay was conducted on a quarterly basis during 1987. The most important factor which determined the abundance and distribution of each... -
FISH CONSERVATION IN SOUTH AFRICAN ESTUARIES: PRESSURES, PROBLEMS AND PROSPECTS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D.P. Cyrus --- Coastal Research Unit of Zululand, Zoology Department, South AfricaA review of the conservation status of fish in the estuarine environment around the South African coastline reveals that some species face serious problems associated either with habitat destruction, and its associated biological, physical and chemical components or exploitation. The... -
CIRCULATION IN HIGHLY STRATIFIED SOUTHERN AFRICAN ESTUARIES
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: J.L. Largier --- , USA J.H. Slinger --- Council for Scientific and Industrial Research, South AfricaThe nature of estuarine circulation under highly stratified conditions is reviewed in the context of southern African estuaries that are small and have a constricted connection to the ocean. While the focus is on the generic hydrodynamic processes and features,... -
A CHARACTERIZATION OF SOUTHERN AFRICAN ESTUARINE SYSTEMS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: A.K. Whitfield --- , South AfricaModifications to the structure and functioning of southern African estuarine systems can be placed into two major categories; those changes that have been driven by global forces such as climatic and sea-level fluctuations, and those that have resulted from direct... -
MASS MORTALITY OF MARINE AND ESTUARINE FISH IN THE SWARTVLEI AND WILDERNESS LAKE SYSTEMS, SOUTHERN CAPE.
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: I.A. Russell --- National Parks Board, South AfricaTwo incidences of mass mortality of fish were recorded in two saline waterbodies (Swartvlei estuary and Rondevlei) in the Wilderness National Park. Species affected were the Knysna seahorse (Hippocampus capensis) and longsnout pipefish (Syngnathus acus) in the Swartvlei estuary, and... -
WATER TEMPERATURE AND THE 1987 FISH KILL AT LAKE ST LUCIA ON THE SOUTH EASTERN COAST OF AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D.P. Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa S. McLean --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaAn unusually cold spell during the winter of 1987 caused a drop in water temperature at Lake St Lucia. This coupled with typical estuarine salinities in the lake resulted in a fish kill. The kill was one of the largest... -
COMPOSITION, ABUNDANCE AND SEASONALITY OF LARVAL FISH IN RICHARDS BAY HARBOUR, KWAZULU-NATAL, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: S. A. Harris --- , , South Africa D. P. Cyrus --- , , South AfricaThe present study examined the composition, abundance and seasonality of fish larvae occurring in Richards Bay Harbour, over an 18-month period from June 1991 to November 1992. Ichthyoplankton samples were collected every six weeks at top, mid and bottom depths... -
A REVIEW OF THE ICHTHYOFAUNA OF THE MHLATHUZE ESTUARY
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: S. P. Weerts --- , , D. P. Cyrus --- , ,The fish fauna of the Mhlathuze estuary was reviewed making reference to surveys dating from 1948 to 1997. The concept of Estuarine Dependence Category was employed to describe species affinities with the marine, estuarine and freshwater environments. -
The icthyofauna of the Mhlathuze coastal lakes: some preliminary results
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SP Weerts DP CyrusThe fish faunas of the four Mhlathuze coastal lakes and the lower river comprise a diverse assortment of over fifty marine, estuarine and freshwater species. Three freshwater species are endemic to KwaZulu-Natal and nine estuarine species are endemic to southern... -
Juvenile fish recruitment through wave-overtopping into a closed subtropical estuary
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Vivier DP CyrusThe fish fauna of the subtropical Nhlabane estuary in northern KwaZulu-Natal was studied during a regional drought over the period 1991–1995. The estuary mouth closed in late 1991, due to the drought and to water abstraction from the system, and... -
A preliminary assessment of impacts on estuarine associated fauna resulting from an intra-basin transfer and fresh water abstraction from aquatic systems in the Richards Bay area of KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: D CyrusAn intra-basin transfer and the abstraction of water from aquatic systems in the Richards Bay area has led to the construction of six barriers which are restricting faunal movement, a reduction of flow to the Mhlathuze and Nhlabane estuaries and... -
Mortality estimates and biological reference points for the Natal stumpnose Rhabdosargus sarba (Pisces: Sparidae) in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NC James BQ Mann PV RadebeA per-recruit stock assessment was undertaken for the sparid Rhabdosargus sarba, which is caught in estuarine and marine shore fisheries in KwaZulu-Natal. Input parameters used in the analyses included age and growth parameters and mortality estimates from catch curves. The... -
Diel and tidal variations in larval fish exchange in the mouth region of the Gamtoos Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NA Strydom TH WooldridgeDiel and tidal variations in density of larval fishes were monitored over one neap and one spring tidal cycle in the mouth region of the warm temperate Gamtoos Estuary, South Africa. Data were collected over two 24h periods, using mixed... -
Primary habitats of the St Lucia Estuarine System, South Africa, and their responses to mouth management
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Ricky Taylor JanineB Adams Sylvi HaldorsenFour primary habitats have been identified in the St Lucia estuarine system, each having a suite of characteristic vegetation types. These can be described as follows: (1) open water; (2) intertidal shoreline; (3) 'dry' shoreline and island (i.e. those habitats... -
The sublethal effects of copper and lead on the haematology and acid-base balance of the groovy mullet, Liza dumerili
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HM Mzimela --- Coastal Research Unit of Zululand, Department of Zoology, South Africa V Wepener --- Coastal Research Unit of Zululand, Department of Zoology, South Africa DP Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaToxicity bioassays were conducted on groovy mullet, Liza dumerili, using copper and lead, in order to assess how these metals affected their blood haematology and acid-base balance. Short-term (96 hours) exposure to lead caused significantly more haematological response [PCO2] than... -
A century of fish research in South African estuaries
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AK Whitfield --- , South AfricaThe history of South African estuarine ichthyology from 1910–2010 is reviewed. The first survey of fishes in a South African estuary was undertaken by Gilchrist in the early 1900s, followed by an extended period between the two world wars when... -
Use of a small, intermittently-open estuary by waterbirds: a case study of the East Kleinemonde Estuary, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: AI Terörde --- Percy FitzPatrick Institute of African Ornithology, South Africa JK Turpie --- , South AfricaLittle is known of the use and importance of South African small, intermittently-open estuaries to waterbirds. Waterbird activities were monitored in a section of the East Kleinemonde Estuary on the south-east coast of South Africa from June 2004 to May... -
ZOOPLANKTON AND ESTUARINE RELICT (BENTHIC) FAUNA IN LAKE MZINGAZI, A FRESHWATER COASTAL LAKE OF NATAL
Item type: Journal Article • Journal: Southern African Journal of Child and Adolescent Mental Health • Authors: B.K. Fowles --- , South Africa C. G.M. Archibald --- , South AfricaLake Mzingazi, a natural, undisturbed freshwater coastal lake in the heart of the Richards Bay municipal area, is threatened by rapid urban and industrial growth. The previously unrecorded composition and distribution of zooplankton in the lake was studied during 1979... -
The Role of Estuaries in South African Fisheries: Economic Importance and Management Implications
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S. J. Lamberth J. K. TurpieExisting catch data for 129 of 255 functional estuaries on the South African coastline were reviewed and the relationships between fish catch and estuary size, type and biogeographical region analysed using simple and multivariate models. The best predictive models were... -
A test of an autonomous underwater vehicle as a monitoring tool in shallow water
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: PA Tester SR Kibler B Hobson RW LitakerThe utility of micro-autonomous underwater vehicles (AUVs) to detect hydrographic features that concentrate phytoplankton cells was evaluated during a study in a shallow tidal estuary. This study represented the first field test of Ranger™, a micro-AUV adapted for environmental applications... -
Impact of tropical storms and drought on the dinoflagellates Karlodinium micrum and Prorocentrum minimum in estuarine rivers of North Carolina, USA
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: EE FensinThe dinoflagellates Karlodinium micrum and Prorocentrum minimum are harmful algal bloom taxa from different parts of the world. They are routinely documented in estuarine rivers in North Carolina, but there have been no known toxic outbreaks of these taxa in... -
Area-use patterns and diel movements of white steenbras Lithognathus lithognathus in a temporarily open/closed South African estuary, inferred from acoustic telemetry and long-term seine-netting data
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RH Bennett --- Department of Ichthyology and Fisheries Science, South Africa PD Cowley --- , South Africa A-R Childs --- Department of Ichthyology and Fisheries Science, South Africa AK Whitfield --- , South AfricaAcoustic telemetry and long-term seine-netting data were used to assess distribution, area use, home range dynamics and movement patterns of estuarine-dependent juvenile white steenbras Lithognathus lithognathus in the temporarily open/closed East Kleinemonde Estuary. Using 15 years of biannual seine-netting data,... -
A review of the ecology and management of temporarily open/closed estuaries in South Africa, with particular emphasis on river flow and mouth state as primary drivers of these systems
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK Whitfield --- , South Africa GC Bate --- Department of Botany, South Africa JB Adams --- Department of Botany, South Africa PD Cowley --- , South Africa PW Froneman --- Department of Zoology and Entomology, South Africa PT Gama --- Department of Botany, South Africa NA Strydom --- Department of Zoology, South Africa S Taljaard --- , South Africa AK Theron --- , South Africa JK Turpie --- , South Africa L van Niekerk --- , South Africa TH Wooldridge --- Department of Zoology, South AfricaResearch in South African temporarily open/closed estuaries that includes studies on the hydrodynamics, sediment dynamics, macronutrients, microalgae, macrophytes, zoobenthos, hyperbenthos, zooplankton, ichthyoplankton, fishes and birds is used as a basis to review the ecology and management of this estuary type... -
Myosotella myosotis (Mollusca: Ellobiidae) — an overlooked, but well-established introduced species in South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: DG Herbert --- , South AfricaMyosotella myosotis is shown to be a well-established alien species in South Africa. Discovered in Port Elizabeth more than 100 years ago, it was initially thought to be indigenous and was described under two different names, but subsequent taxonomic work... -
Thirty years of monitoring traditional fish trap catches at Kosi Bay, KwaZulu-Natal, South Africa, and management implications
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Kyle --- , South AfricaThe catches of the traditional fish traps in the Kosi Bay estuarine lakes were monitored over a 30-year period from 1981 to 2010. Monitoring data were used to provide estimates of, and insights into, catch size and species composition as... -
The trouble with estuarine fisheries in temperate South Africa, illustrated by a case study on the Sundays Estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: PD Cowley --- South African Institute for Aquatic Biodiversity, South Africa A-R Childs --- South African Institute for Aquatic Biodiversity, South Africa RH Bennett --- South African Institute for Aquatic Biodiversity, South AfricaThis study provides empirical data on the exploitation of fishery resources on the Sundays Estuary on the south-east coast of South Africa. Total annual effort was estimated at 63 785 angler-hours, which accounted for an annual yield of 16 214... -
Declining catch per unit effort of an estuarine-dependent fish, Rhabdosargus sarba (Teleostei: Sparidae), in the marine environment following closure of the St Lucia Estuarine System, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: BruceQ Mann Pierre PradervandMonitoring of catch per unit effort of the tropical stumpnose Rhabdosargus sarba in the St Lucia Marine Reserve between 2001 and 2005 revealed a significant decline. A similar decline was evident from shore patrol data collected by Ezemvelo KwaZulu-Natal Wildlife... -
The role of macroinvertebrates in the diets of the dominant fish species in Lake Nokoué, Benin
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: P Gnohossou --- Laboratoire d'Hydrobiologie et d'Aquaculture, P Laleye --- Laboratoire d'Hydrobiologie et d'Aquaculture, P Atachi --- Laboratoire d'Hydrobiologie et d'Aquaculture, J Moreau --- Laboratoire d’Agronomie, Environnement et Écotoxicologie, FranceBetween 2003 and 2006 the diets of 22 fish species, comprising approximately 90% of the Lake Nokoué fish biomass, were analysed. Macroinvertebrates dominated the diet of ten species, fishes were the preferential prey of six fish species, and detritus and... -
Ecological integrity assessment of the fish assemblages of the Matigulu/Nyoni and Umvoti estuaries, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GC O'Brien --- Centre for Aquatic Research, Zoology Department, South Africa R Swemmer --- Centre for Aquatic Research, Zoology Department, South Africa V Wepener --- Centre for Aquatic Research, Zoology Department, South AfricaThe estuarine fish community index (EFCI) and an estuarine fish guild assessment (EFGA) were used in 2004 and 2008 to determine the ecological state and effects of selected ecosystem variables on the Umvoti and Matigulu/Nyoni estuaries. The EFCI indicated that... -
Estuarine use by spotted grunter Pomadasys commersonnii in a South African estuary, as determined by acoustic telemetry
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A-R Childs PD Cowley TF Næsje AJ Booth WM Potts EB Thorstad F ØklandFactors influencing estuarine use and marine excursions by spotted grunter Pomadasys commersonnii in the Great Fish Estuary, South Africa, were studied using manual and automated telemetry methods. In all, 20 individuals, ranging from 362 mm to 698 mm total length... -
Comparison of, and the effects of altered freshwater inflow on, fish assemblages of two contrasting South African estuaries: the cool-temperate Olifants and the warm-temperate Breede
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SJ Lamberth L van Niekerk K HutchingsThis study compares the fish assemblages of the permanently open cool-temperate Olifants and warm-temperate Breede estuaries on the west and south coasts of South Africa respectively, and their responses to altered freshwater flows. Both estuaries have experienced a >35% reduction... -
A multidisciplinary study of a small, temporarily open/closed South African estuary, with particular emphasis on the influence of mouth state on the ecology of the system
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK Whitfield JB Adams GC Bate K Bezuidenhout TG Bornman PD Cowley PW Froneman PT Gama NC James B Mackenzie T Riddin GC Snow NA Strydom S Taljaard AI Terörde AK Theron JK Turpie L van Niekerk PD Vorwerk TH WooldridgeIn 2005/2006 a multidisciplinary research programme that included studies on the hydrodynamics, sediment dynamics, macronutrients, microalgae, macrophytes, zoobenthos, hyperbenthos, zooplankton, ichthyoplankton, fish and birds of the temporarily open/closed East Kleinemonde Estuary was conducted. Particular attention was given to the responses... -
Nitrogen uptake dynamics of a persistent cyanobacterium Cyanothece sp. bloom in Lake St Lucia, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SJ du Plooy --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa AJ Smit --- School of Life Sciences, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa DG Muir --- Department of Biology, Medgar Evers College, USAWorldwide, persistent cyanobacterial blooms are becoming more frequent and are often associated with effects of global climate change. In June 2009, a widespread bloom of the unicellular cyanobacterium, Cyanothece sp., appeared in North Lake and False Bay of Lake St... -
Reproductive biology and distribution of Syngnathus temminckii and S. watermeyeri (Pisces: Syngnathidae) in southern Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Mwale --- South African Institute for Aquatic Biodiversity, South Africa H Kaiser --- Department of Ichthyology and Fisheries Science, South Africa PC Heemstra --- South African Institute for Aquatic Biodiversity, South AfricaThe reproductive biology and distribution of two species of Syngnathus (S. temminckii and S. watermeyeri) were investigated using information from museum specimens, published data, survey data and samples collected during mouth-breaching events of temporarily open/closed estuaries over the period 1950–2011... -
Nutritional condition of fish larvae in South African estuaries: an appraisal of three biochemical methods
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D Costalago --- Department of Zoology, South Africa N Strydom --- Department of Zoology, South Africa C Frost --- Department of Biochemistry and Microbiology, South AfricaEstuaries are exposed to a number of threats and many South African estuarine systems are functionally and structurally altered. The extent to which fish are affected by these alterations is not fully understood. The estuarine round herring Gilchristella aestuaria is... -
Does estuarine health relate to catchment land-cover in the East Kleinemonde system, South Africa?
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: VA Masefield --- Department of Geography, South Africa GK McGregor --- Department of Geography, South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaTemporarily open/closed estuaries in South Africa are being subjected to varying degrees of catchment land-cover transformation. Natural landscapes and hydrological functions are integral to the functioning of estuaries. The relationship between catchment land-cover and the health of the East Kleinemonde... -
Decline of Terebralia palustris in South African mangroves
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JL Raw --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa RH Taylor --- School of Hydrology, South Africa NAF Miranda --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa N Peer --- DST/NRF Research Chair in Shallow Water Ecosystems, South AfricaTerebralia palustris (Linnaeus, 1767), the giant mangrove whelk, is a prominent component of mangrove ecosystem malacofauna in the Indo-West-Pacific region. On the east coast of Africa, the range of T. palustris extends from Kenya to the south-eastern region of South... -
The effect of temperature and salinity on oxygen consumption in the brachyuran crab Cyclograpsus punctatus (Crustacea: Decapoda: Grapsidae)
Item type: Journal Article • Journal: African Zoology • Authors: James J. W. W. Winch --- Department of Zoology and Entomology, South Africa Alan N. Hodgson --- Department of Zoology and Entomology, South AfricaThe aquatic oxygen consumption of the estuarine brachyuran crab, Cyclograpsus punctatus, was investigated after a 24-hour acclimation period at different temperature (12.5, 20, 30°C) and salinity (9, 17.5, 35, and 44°) combinations . Salinity had no significant effect on oxygen... -
First assessment of estuarine space use and home range of juvenile white steenbras, Lithognathus lithognathus
Item type: Journal Article • Journal: African Zoology • Authors: R. H. Bennett --- Department of Ichthyology and Fisheries Science, South Africa A. R. Childs --- Department of Ichthyology and Fisheries Science, South Africa P. D. Cowley --- South African Institute for Aquatic Biodiversity, South Africa T. F. Næsje --- Norwegian Institute for Nature Research, Norway E. B. Thorstad --- Norwegian Institute for Nature Research, Norway F. Økland --- Norwegian Institute for Nature Research, NorwayThe spatial dynamics and home range sizes of early juvenile white steenbras (Lithognathus lithognathus Cuvier, 1829) in the permanently open Great Fish Estuary, South Africa, were assessed using acoustic telemetry. Seven individuals (154–184 mm fork length) tagged with acoustic transmitters... -
Plankton dynamics associated with the convergence zone of a shear front in the permanently open Kowie Estuary, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: M. Kruger --- Department of Ichthyology and Fisheries Science, South Africa N. A. Strydom --- Department of Zoology, South AfricaEstuarine frontal systems are thought to play an important role in plankton accumulations in estuaries. However, knowledge surrounding these estuarine circulation patterns is not clear, and consensus regarding the importance of fronts has yet to be reached. A full appraisal... -
Diet of largemouth bass, Micropterus salmoides (Centrarchidae), an invasive alien in the lower reaches of an Eastern Cape river, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: R.J. Wasserman --- Department of Zoology, South Africa N.A. Strydom --- Department of Zoology, South Africa O.L.F Weyl --- South African Institute for Aquatic Biodiversity, South AfricaLargemouth bass (Micropterus salmoides) have been introduced to many South African river systems where they become invasive and pose a threat to native biota. The diets of small (32–138 mm TL) and large (192–448 mm TL) sized bass were analysed... -
A novel methodology for the rapid assessment of waterbird vulnerability to disturbance
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Kate JH England --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South Africa Colin Jackson --- A Rocha Kenya, Mwamba Bird Observatory and Field Study Centre, Kenya Philip AR Hockey --- Percy FitzPatrick Institute of African Ornithology, DST–NRF Centre of Excellence, South AfricaA methodology for rapidly assessing the vulnerability of waterbirds to disturbance was tested at Sabaki estuary, Kenya. Three variables were employed to measure the responses of 15 species: (1) bird density, (2) minimum distance of birds from a stationary disturbance... -
Impact of marine inundation after a period of drought on the lakeshore vegetation of Lake St Lucia, South Africa: resilience of estuarine vegetation
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: EJJ Sieben --- Department of Plant Sciences, South Africa WN Ellery --- Department of Geography, South Africa BW Dullo --- Center for Energy and Environmental studies, The Netherlands AP Grootjans --- Center for Energy and Environmental studies, The NetherlandsThe shore of Lake St Lucia in the vicinity of Catalina Bay, in the southern part of the lake, receives freshwater input as surface and groundwater seepage from the adjacent elevated coastal plain. Vegetation, water quality and landform were recorded... -
Affinities of some common estuarine macroinvertebrates to salinity and sediment type: empirical data from Eastern Cape estuaries, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Peter R. Teske --- Department of Zoology, South Africa Tris H. Wooldridge --- Department of Zoology, South AfricaFourteen species of subtidal macrobenthos present in thirteen Eastern Cape estuaries, South Africa, were compared with regard to correlations with two important environmental variables (salinity and sediment mud content). Species were divided into five different faunal components based on their... -
Growth and longevity of Exosphaeroma hylocoetes (Isopoda) under varying conditions of salinity and temperature
Item type: Journal Article • Journal: African Zoology • Authors: T.O. Henninger --- Department of Zoology and Entomology, South Africa P.W. Froneman --- Department of Zoology and Entomology, South Africa A.J. Booth --- Department of Ichthyology and Fisheries Science, South Africa A.N. Hodgson --- Department of Zoology and Entomology, South AfricaThe effect of temperature (15 and 25°C) and salinity (15 and 35 practical salinity units) combinations on the growth and longevity of the South African estuarine isopod Exosphaeroma hylocoetes was investigated and data analysed using the logistic growth model. No... -
Movement behaviour of alien largemouth bass Micropterus salmoides in the estuarine headwater region of the Kowie River, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Taryn S Murray --- South African Institute for Aquatic Biodiversity, South Africa Mandla L Magoro --- South African Institute for Aquatic Biodiversity, South Africa Alan K Whitfield --- South African Institute for Aquatic Biodiversity, South Africa Paul D Cowley --- South African Institute for Aquatic Biodiversity, South AfricaThe movement behaviour of largemouth bass Micropterus salmoides in the estuarine headwater region of the Kowie River, South Africa, was investigated using passive acoustic telemetry. Ten adult fish were tagged and released in four discrete pools below a weir that... -
Age and growth of Cape stumpnose Rhabdosargus holubi (Pisces: Sparidae) in the Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MW Farthing --- Department of Ichthyology and Fisheries Science, South Africa NC James --- South African Institute for Aquatic Biodiversity, South Africa WM Potts --- Department of Ichthyology and Fisheries Science, South AfricaRhabdosargus holubi is a small (maximum weight=2.4 kg) yet important fishery species in the estuaries of the south-east coast of South Africa. Little is known of its biology and specifically its growth rate, which is essential for sustainable management of the... -
Past and present fish species recorded in the estuarine Lake Ichkeul, northern Tunisia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Shaiek --- Research Unit Ecosystems and Aquatic Resources (UR13AGRO1), National Agronomy Institute of Tunisia (INAT), Tunisia C Fassatoui --- Research Unit Ecosystems and Aquatic Resources (UR13AGRO1), National Agronomy Institute of Tunisia (INAT), Tunisia MS Romdhane --- Research Unit Ecosystems and Aquatic Resources (UR13AGRO1), National Agronomy Institute of Tunisia (INAT), TunisiaLake Ichkeul in northern Tunisia is a Ramsar site, a MAB Biosphere Reserve and a UNESCO World Heritage Site. The system is one of the most important coastal wetlands in North Africa, especially as an over-wintering area for migratory birds,... -
Influence of prey abundance and abiotic factors on the long-term home-range and movement dynamics of spotted grunter Pomadasys commersonnii in an intermittently open estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BA Maree --- Department of Ichthyology and Fisheries Science, South Africa PD Cowley --- Department of Ichthyology and Fisheries Science, South Africa TF Næsje --- South African Institute for Aquatic Biodiversity, South Africa A-R Childs --- Department of Ichthyology and Fisheries Science, South Africa AI Terörde --- Arcus Consulting, South Africa EB Thorstad --- Norwegian Institute for Nature Research, NorwayLong-term home-range and movement dynamics of spotted grunter Pomadasys commersonnii and the distribution of their dominant prey, the sandprawn Callichirus kraussi, were investigated in the intermittently open East Kleinemonde Estuary, South Africa. In addition, the effects of fish length, diel... -
Ingestion rates and grazing impact of the brackwater mussel Brachidontes virgiliae in Lake St Lucia, iSimangaliso Wetland Park, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HA Nel --- School of Life Sciences, South Africa R Perissinotto --- School of Life Sciences, South Africa NK Carrasco --- School of Life Sciences, South AfricaBivalves feed on a combination of phytoplankton and zooplankton and have the potential to impact considerably the planktonic biomass, especially when they occur in high densities, such as in oyster and mussel beds. The brackwater mussel Brachidontes virgiliae is numerically... -
Stable isotope analysis of consumer food webs indicates ecosystem recovery following prolonged drought in a subtropical estuarine lake
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MS Bird --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa NAF Miranda --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa N Peer --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa JL Raw --- DST/NRF Research Chair in Shallow Water Ecosystems, South AfricaAssessing changes in food-web structure provides a useful monitoring tool for gauging the resilience of ecosystems in the face of climatic impacts. We consider the ecological resilience of a large estuarine lake (St Lucia Estuary, South Africa) in the wake... -
Using stable isotope analysis to study the diet of Gilchristella aestuaria larvae: preliminary insights into the foodwebs of six South African estuaries
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: D Costalago --- Department of Ecology, Environment and Plant Sciences, Sweden NAF Miranda --- DST/NRF Research Chair in Shallow Water Ecosystems, Department of Zoology, South Africa NA Strydom --- Department of Zoology, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, Department of Zoology, South AfricaSouth African estuarine systems are becoming increasingly altered by anthropogenic and environmental factors, but the consequences of such changes for these systems are still not fully understood. The most common approach for evaluating the ecological status of aquatic systems is... -
Estuarine and coastal connectivity of an estuarine-dependent fishery species, Pomadasys commersonnii (Haemulidae)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MH Dames --- Department of Ichthyology and Fisheries Science, South Africa PD Cowley --- South African Institute for Aquatic Biodiversity, South Africa A-R Childs --- Department of Ichthyology and Fisheries Science, South Africa RH Bennett --- South African Institute for Aquatic Biodiversity, South Africa EB Thorstad --- Norwegian Institute for Nature Research, Norway TF Næsje --- Norwegian Institute for Nature Research, NorwayUnderstanding the level of connectivity between estuarine and coastal waters is essential for appropriate management of estuarine-associated taxa. Most studies have focused on the role of a single estuary, while limited research exists on the importance of multiple estuaries to... -
Evaluating the effects of catch-and-release angling on Cape stumpnose Rhabdosargus holubi in a South African estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: NK Arkert --- Department of Ichthyology and Fisheries Science, South Africa A-R Childs --- Department of Ichthyology and Fisheries Science, South Africa MC Parkinson --- Department of Ichthyology and Fisheries Science, South Africa AC Winkler --- Department of Ichthyology and Fisheries Science, South Africa E Butler --- Department of Ichthyology and Fisheries Science, South Africa S Mannheim --- Department of Ichthyology and Fisheries Science, South Africa WM Potts --- Department of Ichthyology and Fisheries Science, South AfricaFisheries managers are increasingly promoting catch-and-release (C&R) to manage recreationally angled fish stocks. Despite this, there is a scarcity of information on the effects of C&R on estuarine-dependent species. Cape stumpnose Rhabdosargus holubi dominates the recreational fisheries catch and provides... -
A comparison between the morphological and molecular approach to identify the benthic diatom community in the St Lucia Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Nunes --- Botany Department and Institute for Coastal and Marine Research, South Africa JB Adams --- Botany Department and Institute for Coastal and Marine Research, South Africa S Van Aswegen --- Department of Biochemistry and Microbiology, South Africa GF Matcher --- Department of Biochemistry and Microbiology, South AfricaThe use of diatoms as bioindicators to detect human-induced change is a globally accepted monitoring tool. DNA metabarcoding is an effective complementary tool to standard microscopic methods for species identification, providing reliable and timeous diatom assessments in a range of... -
An Estuary Ecosystem Classification that encompasses biogeography and a high diversity of types in support of protection and management
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L van Niekerk --- Council for Scientific and Industrial Research (CSIR), South Africa JB Adams --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa NC James --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa SJ Lamberth --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa CF MacKay --- Oceanographic Research Institute, SAAMBR, South Africa JK Turpie --- South African Institute for Aquatic Biodiversity, South Africa A Rajkaran --- Biodiversity and Conservation Biology, South Africa SP Weerts --- Council for Scientific and Industrial Research (CSIR), South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity, South AfricaFor nearly three decades, the Whitfield (1992) characterisation scheme served as a reference framework to type South African estuaries. We outline a revised ecosystem classification scheme that incorporates biogeographical zonation and introduces new types. Coastal outlets were re-categorised as estuaries... -
Restoration of Lake St Lucia, the largest estuary in South Africa: historical perceptions, exploitation, management and recent policies
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NT Forbes --- Marine and Estuarine Research, Hyper-by-the-Sea, South Africa AT Forbes --- Marine and Estuarine Research, Hyper-by-the-Sea, South Africa B James --- iSimangaliso Wetland Park Authority, Dredger Harbour, South AfricaRestoration of estuarine function to the Lake St Lucia system, the largest estuary in South Africa, was initiated in 2010. Significant change began with the reversal of a mouth management policy that was adopted in 1952 and maintained for the... -
Multiscale drivers of hippopotamus distribution in the St Lucia Estuary, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Alexa S Prinsloo --- , South Africa Deena Pillay --- , South Africa M Justin O'Riain --- , South AfricaThis study provides preliminary data on predictors of Hippopotamus amphibius (Linnaeus, 1758; hippo) distribution in St Lucia Estuary, the largest estuarine system in Africa and a key habitat for one of South Africa’s largest hippo populations. We use binary logistic... -
Strengthening the DNA barcode reference library for South African estuarine macrofauna
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Fagg --- , South Africa NL Phair --- , South Africa L Claassens --- , South Africa RSK Barnes --- , South Africa S von der Heyden --- , South AfricaSeagrass ecosystems face many anthropogenic pressures, yet globally there is a lack of knowledge of their associated biodiversity. Molecular barcoding can aid in biomonitoring efforts, but few South African invertebrates are accounted for. We provide 48 new sequences for 15... -
Bull shark Carcharhinus leucas recruitment into the St Lucia Estuary, South Africa, after prolonged mouth closure, and the first observation of a neonate bull shark preyed on by a Nile crocodile Crocodylus niloticus
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Daly --- , South Africa P Le Noury --- , United Kingdom TN Hempson --- , Mozambique M Ziembicki --- , Mozambique JM Olbers --- , South Africa GM Brokensha --- , South Africa BQ Mann --- , South AfricaEstuaries provide critical nursery habitat for juvenile bull sharks Carcharhinus leucas, as they have the ability to withstand a wide range of salinities. St Lucia is the largest estuarine lake in Africa and was once a key nursery for bull... -
Spawning observations of Pomadasys commersonnii in the marine section of the Knysna estuarine bay, Western Cape, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: EC Butler --- , South Africa A-R Childs --- , South Africa MKS Smith --- , South Africa RM Foster --- , South Africa WM Potts --- , South AfricaKnowledge of the location and timing of spawning events is critical for fisheries management. As is the case for many southern African fishes, the spotted grunter Pomadasys commersonnii was historically thought to reproduce in the coastal waters off KwaZulu-Natal Province... -
The changing status of important marine fishery species in selected South African estuaries
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa BQ Mann --- Rhodes University, South AfricaThis review examines the changing status of 10 estuary-dependent marine fish species in 10 South African estuarine systems, ranging from the Kosi Estuary in the northeast to the Berg Estuary in the southwest. In all of these systems, the selected... -
South African coastal outlets and estuaries: what defines an estuary versus an outlet?
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Alan K Whitfield --- South African Institute for Aquatic Biodiversity, South AfricaThis review examines the transition of coastal micro-outlets to micro-estuaries, to fully functional and species rich estuaries of various types. The definitions of the different types of microsystems are reviewed and it is apparent that an estuary is not simply... -
Zooplankton composition following an artificial mouth breaching event in Lake St Lucia, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NK Carrasco --- University of KwaZulu-Natal, South Africa S Ramdass --- University of KwaZulu-Natal, South AfricaLake St Lucia is one of the most important estuarine systems in South Africa, but the long history of anthropogenic intervention has threatened its integrity. With the exception of sporadic overtopping events and periodic marine connectivity via the uMfolozi River,... -
Future of the IUCN Endangered white steenbras Lithognathus lithognathus (Sparidae) – a tale of two estuaries
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa MKS Smith --- Rhodes University, South AfricaThis review draws on a long history of ichthyological and fisheries research to examine the changing stock status of the estuary-dependent white steenbras Lithognathus lithognathus in the South African Swartkops and Knysna estuaries. The available evidence points to a major... -
A new species of Malacoceros (Annelida, Polychaeta, Canalipalpata, Spionidae) from urban waters in Gabon
Item type: Journal Article • Journal: African Zoology • Authors: Nicolas Lavesque --- Université de Bordeaux, CNRS, Bordeaux INP, EPOC, France Aimé Roger Nzigou --- Université des Sciences et Techniques de Makusu (USTM), Gabon Guillemine Daffe --- Université de Bordeaux, Observatoire Aquitain des Sciences de l’Univers, France Johann Ludovic Martial Happi --- Université des Sciences et Techniques de Makusu (USTM), Gabon Geon Hyeok Lee --- National Institute of Biological Resources, Seo-gu, Korea Karin Meißner --- Senckenberg am Meer, Deutsches Zentrum für Marine Biodiversitätsforschung (DZMB), GermanyA new species of Malacoceros is described from estuarine equatorial waters in Libreville (Gabon, West Africa). During a recent environmental study aimed to assess the urban impact on an estuarine ecosystem near Libreville, the collection of sediment samples from the... -
Spatio-temporal dynamics of anthropogenic land-use pressures on temporarily closed estuaries in South Africa: a four-decade remote sensing analysis
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B McKelvey --- Oceanographic Research Institute, South African Association for Marine Biological Research, South Africa CF MacKay --- Oceanographic Research Institute, South African Association for Marine Biological Research, South AfricaLand-cover change is the leading cause of habitat loss globally. The extent of estuarine habitat loss and land-use pressures are understudied in South Africa, particularly in the numerically dominant temporarily closed estuaries. Remote sensing techniques are effective tools for monitoring...