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Assessment of the recreational linefishery in selected Eastern Cape estuaries: trends in catches and effort
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: P. Pradervand D. BairdBoat-based creel surveys were used to collect catch and effort data on the shore- and boat-based linefisheries of the Kromme, Gamtoos, Swartkops, Sundays, Bushmans, Kariega, Kowie and Great Fish estuaries in the Eastern Cape, South Africa, from January 1996 to... -
NUTRIENTS IN AQUATIC ECOSYSTEMS: AN INTRODUCTION TO SIMILARITIES BETWEEN FRESHWATER AND MARINE ECOSYSTEMS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: P Chapman --- , South Africa JA Thornton --- , South Africa -
NUTRIENTS AND THE PRODUCTIVITY OF ESTUARINE AND COASTAL MARINE ECOSYSTEMS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: S.W. Nixon --- Marine Ecosystems Research Laboratory, United States of America C.A. Oviatt --- Marine Ecosystems Research Laboratory, United States of America J. Frithsen --- Marine Ecosystems Research Laboratory, United States of America B. Sullivan --- Marine Ecosystems Research Laboratory, United States of AmericaRecent research on estuarine and coastal marine systems has revealed two particularly interesting things about nutrients and productivity. First is the observation that these areas are among the most intensively fertilized environments on earth. Second is the common finding that... -
TURBIDITY AND OTHER PHYSICAL FACTORS IN NATAL ESTUARINE SYSTEMS PART 1: SELECTED ESTUARIES
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: D.P. Cyrus --- Department of Zoology, South AfricaData on turbidity and the factors influencing it, such as wind and substratum, were collected from eight representative estuaries along the Natal Coast. The results showed that Natal Estuaries can be divided into one of four groups, according to the... -
TURBIDITY GRADIENTS IN TWO INDO-PACIFIC ESTUARIES AND THEIR INFLUENCE ON FISH DISTRIBUTION
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D.P. Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaResearch undertaken in two widely separated estuaries in the Indo-Pacific, showed that both have distinct turbidity gradients. In the turbid St Lucia System, on the South East Coast of Africa (range 2 to 568 Nephelometric Turbidity Units (NTU)), different turbidity... -
FLUX OF INORGANIC NUTRIENTS AND PARTICULATE CARBON BETWEEN A SPARTINA MARITIMA SALT MARSH AND THE SWARTKOPS ESTUARY, EASTERN CAPE
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D. Baird --- Department of Zoology, South Africa P. E.D. Winter --- Department of Zoology, South AfricaThe flux of dissolved inorganic nutrients (NH4-N, NO2-N, NO3-N, SRP) and suspended particulates (particulate organic carbon POC, and particulate inorganic carbon PIC) was measured across the mouth of a small creek draining a portion of the intertidal Spartina salt marsh... -
FURTHER COMMENT ON THE RESPONSE OF EASTERN CAPE PROVINCE ESTUARIES TO VARIABLE FRESHWATER INFLOWS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: B.R. Allanson --- , South Africa G. H.L. Read --- , South AfricaRiver flow patterns in the Kariega, Great Fish and Keiskamma estuaries, South Africa are examined to assess the impact variation in flow has upon the delivery of inorganic nutrients, total organic carbon, primary productivity and the heterotrophic components, bacteria and... -
Preliminary study on the food web structure of two contrasting estuaries along the Eastern Cape coast, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW FronemanWater column profiles, surface macronutrient concentrations, size fractionated primary production and grazing by protozooplankton were investigated at 8 stations in the Kariega and Great Fish River estuaries in autumn (May) 1999. As a result of the low freshwater influx, the... -
Influence of salinity and temperature on the larval development of the crown crab, Hymenosoma orbiculare (Crustacea: Brachyura: Hymenosomatidae)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Isabelle Papadopoulos BrentK Newman DaveS Schoeman TrisH WooldridgeAlthough the crab Hymenosoma orbiculare appears to complete its entire life cycle within estuaries, the salinity and temperature requirements for its successful larval development are not known. The present study therefore evaluated larval response to salinity and temperature in combination... -
Population demographics of Palaemon peringueyi (Macpherson 1990) (Decapoda: Palaemonidae) in a small intermittently open Eastern Cape estuary
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW FronemanThe population demographics of the caridean shrimp Palaemon peringueyi was investigated monthly at four sites over a period of one year in the small, intermittently-open Grants River Estuary situated on the south-east coastline of southern Africa. Mean total abundance and... -
Food web structure in three contrasting estuaries determined using stable isotope (∂13C) analysis
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW Froneman --- Department of Zoology and Entomology, South AfricaFood web structure in three contrasting estuaries, the freshwater-deprived Kariega, the freshwater-dominated Great Fish River and the temporarily open/closed Kasouga estuary, along the south-east coast of southern Africa was investigated in summer (1–4 November) 2000 by employing stable carbon (∂13C)... -
Fish sampling in the marine-dominated Kariega Estuary, South Africa, using a demersal otter trawl: day/night effects
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SE Bailey --- , South Africa NC James --- , South AfricaVery few demersal fish assemblage studies using otter trawls in estuaries have been done in South Africa and none of these have tested for the effects of diel period. This study aimed to test whether diel period affects otter trawl... -
Preliminary documentation and assessment of fish diversity in sub-Saharan African estuaries
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK WhitfieldLists of indigenous fish species sampled in cool-temperate, warm-temperate, subtropical and tropical estuaries in sub-Saharan Africa were compiled from both published and unpublished data. Comparisons were conducted at the species and family level between the fish assemblages recorded in the... -
Interactions between Zostera capensis, Callianassa kraussi and Upogebia africana: deductions from field surveys in Langebaan Lagoon, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Siebert GM BranchCallianassid sandprawns and eelgrasses have been postulated to have mutually negative effects on each other. The relationship between Callianassa kraussi and Zostera capensis was investigated in Langebaan Lagoon on the west coast of South Africa by correlative field surveys. Seven... -
Spatial and seasonal distribution patterns of the ragged-tooth shark Carcharias taurus along the coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ML Dicken MJ Smale AJ BoothCatches from competitive shore-anglers, inshore boat-based anglers and sightings by spearfishers and divers were used to infer the spatial and seasonal movement patterns of young-of-the-year (<1.2m TL), juvenile (1.2–1.8m TL), sub-adult (1.8–2.4m TL) and adult (>2.4m TL) ragged-tooth sharks Carcharias... -
Assessment of the abundance and distribution of burrowing sandprawns and mudprawns (Callichirus and Upogebia species) in Langebaan Lagoon, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P Nel --- West Coast National Park, South Africa GM Branch --- Marine Biology Research Centre, Zoology Department, South AfricaA survey of sandprawns and mudprawns was undertaken in intertidal and subtidal zones in Langebaan Lagoon, West Coast National Park, South Africa, to determine their stock status and to gain an understanding of the spatio-temporal patterns in abundance and distribution... -
Water quality in South African temporarily open/closed estuaries: a conceptual model
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GavinC Snow Susan TaljaardOf the five types of estuaries found in South Africa, temporarily open/closed estuaries comprise approximately 70% of the total. This paper provides an overview and a simple conceptual model of the water quality features and characteristics of temporarily open/closed estuaries... -
A preliminary investigation of winter daily food intake by four small teleost fish species from the Igoda Estuary, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LukhanyisoU Vumazonke TebelloS Mainoane Tembela Bushula EvgenyA PakhomovThe winter diet and daily ration of four small size classes of estuary-associated fishes, Rhabdosargus holubi, Gilchristella aestuaria, Glossogobius callidus and Monodactylus falciformis, from the temporarily open/closed Igoda Estuary were investigated. The diet of G. callidus was dominated by gammarid... -
The importance of estuarine-derived carbon for the nearshore marine environment: studies on two contrasting South African estuaries
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PD Vorwerk --- Department of Zoology and Entomology, South Africa PW Froneman --- Department of Zoology and Entomology, South AfricaThe food web structure within and adjacent to two permanently open estuaries with contrasting flow regimes along the south-eastern coast of South Africa was investigated employing stable isotope analysis. The Kariega Estuary is considered a freshwater-deprived system, while the Great... -
Assessment of recreational boat-angling in a large estuarine embayment in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BI Everett ST FennessyAn access point study was conducted from June 2002 to May 2003 to collect fishing effort, catch, catch composition and socio-economic information from the recreational estuarine boat-fishery in Richards Bay Harbour on the east coast of South Africa. An estimated... -
Few fish but many fishers: a case study of shore-based recreational angling in a major South African estuarine port
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LE Beckley ST Fennessy BI EverettRichards Bay is a subtropical estuary that has been extensively dredged to accommodate one of Africa's largest commercial ports. In the non-commercial areas of the harbour, shore-based angling is a popular recreational activity, but little is known about the anglers... -
Diurnal and water salinity-dependent metabolic activity of juvenile white steenbras Lithognathus lithognathus
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: K Kandjou --- Department of Ichthyology and Fisheries Science, South Africa H Kaiser --- Department of Ichthyology and Fisheries Science, South AfricaThe euryhaline white steenbras Lithognathus lithognathus is an important estuarine-dependent fish species in the South African marine and estuarine environment. Its tolerance to water quality fluctuations, in particular its metabolic rate responses to salinity changes, has not been studied. In... -
The influence of selected environmental parameters on the distribution of the dominant demersal fishes in the Kariega Estuary channel, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Naomi Richardson --- Department of Ichthyology and Fisheries Science, South Africa Alan K. Whitfield --- South African Institute for Aquatic Biodiversity, South Africa Angus W. Paterson --- South African Institute for Aquatic Biodiversity, South AfricaThe Kariega Estuary channel was sampled using an otter trawl and the demersal fish catch analysed using the PRIMER statistical package. A biological-environmental (BIOENV) analysis was undertaken using the catch per unit effort ichthyofaunal data from the spring/summer period of... -
Description and ecology of larvae of Glossogobius callidus and Redigobius dewaali (Gobiidae) from temperate South African estuaries
Item type: Journal Article • Journal: African Zoology • Authors: Nadine A. Strydom --- South African Institute for Aquatic Biodiversity, South Africa Francisco J. Neira --- Marine Research Laboratories, Tasmanian Aquaculture and Fisheries Institute (TAFI), University of Tasmania, AustraliaThis paper describes the morphology and ecology of the larvae and early juveniles of two common gobiids in warm temperate South African estuaries. The early developmental stages of Glossogobius callidus and Redigobius dewaali were collected during plankton surveys in seven... -
Marine connectivity and fish length frequencies of selected species in two adjacent temporarily open/closed estuaries in the Eastern Cape Province, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Poogendri Reddy --- South African Institute for Aquatic Biodiversity, South Africa Nicola C. James --- 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 effects of timing, frequency and duration of mouth opening and marine overwash events on fish assemblages in two, adjacent temporarily open/closed estuaries were investigated. Sampling was conducted biannually over two years during summer and winter, using selective sampling gear... -
Disentangling the identities and distribution patterns of the introduced beachfleas Orchestia gammarellus and Platorchestia platensis (Crustacea: Amphipoda: Talitridae) in South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Natalie Diemer --- Department of Biological Sciences and Centre for Invasion Biology, South Africa Charles L Griffiths --- Department of Biological Sciences and Centre for Invasion Biology, South Africa Alan Hodgson --- Department of Zoology and Entomology, South AfricaTwo introduced beachfleas, Orchestia gammarellus and Platorchestia platensis, have been recorded from South Africa, but have been misidentified by some earlier researchers and, prior to this study, each was also known from just a few, scattered observations, such that their... -
Overview and status of estuarine microphytobenthos ecological research in South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Dalu --- Department of Ecology and Resource Management, South Africa JB Adams --- Department of Botany, South Africa JC Taylor --- South African Institute for Aquatic Biodiversity, South Africa GC Bate --- Department of Botany, South Africa M Nunes --- Department of Botany, South Africa PW Froneman --- Department of Ecology and Resource Management, South Africa RJ Wasserman --- South African Institute for Aquatic Biodiversity, South AfricaThis article presents a historical overview of estuarine microphytobenthos (MPB) research in South Africa published over the period 1950 to the present, highlighting major milestones, challenges and estuarine management problems, as well as future research needs within the South African... -
Mesozooplankton of the Kosi Bay lakes, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HL Jerling --- Department of Zoology and Coastal Research Unit of Zululand, South Africa SP Weerts --- Department of Zoology and Coastal Research Unit of Zululand, South AfricaThe Kosi coastal lake system, a chain of four interconnected basins, is located in the subtropical north-eastern corner of South Africa. Little information is available on zooplankton of the system and the main aim of this study is to report... -
Review of progress with integrated coastal management in South Africa since the advent of democracy
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Sowman --- Environmental and Geographical Science Department, South Africa N Malan --- Branch: Oceans and Coasts, Department of Environmental Affairs (DEA), South AfricaWorldwide, coastal environments are recognised as complex systems of immense biophysical, socioeconomic and cultural value. In South Africa, the promulgation of the Coastal White Paper in 2000, and the Integrated Coastal Management (ICM) Act of 2008, signalled a significant paradigm... -
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... -
Counting waterbirds on holiday: a snapshot for one Eastern Cape estuary
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: RLG Mullins --- , South Africa AJFK Craig --- , South AfricaOver a ten-year period, each December the same observer counted waterbirds on the same stretch of the Kariega River in the Eastern Cape, South Africa. The site surveyed is dominated by waders, with variable numbers of other feeding guilds. Piscivorous... -
The ecology of coastal wetland ponds created by diamond mining in southern Namibia. 2. Saltmarsh vegetation
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Maritz --- , South Africa D Pillay --- , South Africa GM Branch --- , South AfricaDiamond mining on the southern Namibian coastline has created multiple large coastal ponds of up to 380 000 m2 adjacent to the coastline, as the sea overtops erected seawalls or seeps into excavated areas. These ponds span ages of 1–38... -
The ecology of coastal wetland ponds created by diamond mining in southern Namibia. 3. Fish
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Maritz --- University of Cape Town, South Africa CG Attwood --- University of Cape Town, South Africa D Pillay --- University of Cape Town, South Africa GM Branch --- University of Cape Town, South AfricaDiamond mining in southern Namibia creates seawalls that hold the ocean at bay, yet seawater overwashes or seeps through to fill landward excavated areas, forming numerous coastal ponds that reach 380 000 m2. These ponds span ages of 1–40 years,... -
Spatial patterns and environmental drivers of demersal fish assemblages in the Swartkops and Sundays estuarine to marine seascapes, South Africa
Item type: Journal Article • Journal: Anthropology Southern Africa • Authors: P Nodo --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AR Childs --- Rhodes University, South Africa P Pattrick --- Nelson Mandela University, South Africa NC James --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaEstuaries are often observed as the boundary between the ocean and the river, separating coastal environments, rather than being seen as a continuum. Owing to insufficient research on demersal fish communities across nearshore marine to estuarine habitats, particularly in South...