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HETEROTROPHIC UTILIZATION OF ACETATE AND GLUCOSE IN SWARTVLEI, SOUTH AFRICA
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: RichardD. Robarts --- , South AfricaThe utilization of dissolved organic compounds in Swartvlei was measured by the addition of single concentrations of 14C-labelled acetate and glucose to water samples, The results indicated acetate uptake was greatest in the aerobic zone while glucose was predominantly utilized... -
DECOMPOSITION IN ESTUARINE ECOSYSTEMS
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: MH Schleyer --- , South AfricaThe varied sources of estuarine plant detritus and the processes and organisms involved in its decomposition are discussed in this review. In the case of emergent and peripheral vegetation, microbial decomposition commences in the phylloplane, with fairly rapid leaching of... -
THE LAKE ST. LUCIA SYSTEM—A RESEARCH ASSESSMENT
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D.P. Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaThis paper assesses the research undertaken at Lake St. Lucia over the past 25 years based on over 300 documents from that period. Trends related to both time and subject matter are evident, and these are considered in relation to... -
Covariance Analysis of Chlorophyll Distribution in the Sundays River Estuary, Eastern Cape
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: T. Hilmer --- Department of Botany, South Africa G.C. Bate --- Department of Botany, South AfricaAn analysis of covariance performed on chlorophyll a distribution data from the Sundays River estuary identified five persistent water masses with significantly different chlorophyll a contents. These corresponded to different hydrodynamic regions within the estuary. The relationship between salinity and... -
The Evolution of Thermohaline Structure in a Closed Estuary
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: J.H. Slinger --- , South Africa J.L. Largier --- , U.S.A.Following the closure of the mouth of the Palmiet estuary in February 1988, the thermohaline structure was recorded at approximate weekly intervals. The evolution of the two-layer structure was studied and the mixing processes causing the changes were determined. Vertical... -
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,... -
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... -
RELATIVELY NEGATIVE δ13C RATIOS OF MESOZOOPLANKTON IN THE SUNDAYS RIVER ESTUARY, COMMENTS ON POTENTIAL CARBON SOURCES
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: H.L. Jerling --- Department of Zoology, South Africa T.H. Wooldridge --- Department of Zoology, South AfricaMesozooplankton, submergent and fringing macrophytes and particles suspended in the water column in the Sundays River estuary South Africa were analyzed for δ13C isotope ratios. Highly negative values (−28.3‰ to −32.0‰) for the mesozooplankton species suggest the possibility of phytoplankton... -
SALINITY, FLOODS AND THE INFAUNAL MACROBENTHIC COMMUNITY OF THE ST LUCIA ESTUARY, KWAZULU-NATAL, SOUTH AFRICA
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: R. K. Owen --- , , South Africa A. T. Forbes --- , , South AfricaThe St Lucia estuary and lake comprise some 80 % of the estuarine area of KwaZulu-Natal. The system is subject to floods and hypersaline conditions, the latter twice exceeding 100 since 1970. The lake is connected to the sea by... -
DUNE MINING AND THE NHLABANE SYSTEM: CAN BIODIVERSITY AND THE NURSERY FUNCTION BE MAINTAINED?
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D. P. Cyrus --- , , South Africa V. Wepener --- , , South AfricaA four year study of the Nhlabane Estuary and Lake System was undertaken over the period 1992 to 1995. Data gathered clearly showed that in terms of ichthyofauna, the estuary plays an important role as a nursery ground for juveniles... -
MANAGING THE ST. LUCIA ESTUARY—MESSAGES FROM THE MUD
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: R. K. Owen --- , , South Africa A. T. Forbes --- , , South AfricaThe infaunal macrobenthic community of the St Lucia estuary has been exposed to natural disturbance in the form of salinity fluctuations arising from floods and hypersaline conditions, and human-induced interference arising from dredging and beam trawling. The responses of the... -
COMMENTS ON THE WATER QUALITY OF THE MHLATHUZE ESTUARY IN RELATION TO DETERMINING THE ECOLOGICAL INTEGRITY CLASS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: V. Wepener --- , , South Africa L. A. Vermeulen --- , , South AfricaWater quality forms an integral component of the determination of the Ecological Reserve of a water resource. This paper presents the available historical and current information on the water quality of the Mhlathuze estuary, The data were assessed in order... -
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. -
A REVIEW OF THE MACROBENTHIC FAUNA OF THE MHLATHUZE ESTUARY: SETTING THE ECOLOGICAL RESERVE
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: C. F. Mackay --- , , South Africa D. P. Cyrus --- , , South AfricaThis paper reviews historical and current ecological information on macrobenthos from the Mhlathuze Estuary before and after development of the Richards Bay Harbour. The fauna is described in terms of the potential influence of a change in freshwater inflow to... -
A REVIEW OF THE AQUATIC AVIFAUNA OF THE MHLATHUZE ESTUARY
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D. P. Cyrus --- , , South AfricaThis paper is the first published review of the aquatic avifauna of the Mhlathuze Estuary. It also uses a regional approach in order to determine the potential for certain hitherto unrecorded species to occur there. The study shows that there... -
ZOOPLANKTON OF THE MHLATHUZE (RICHARDS BAY) ESTUARY: AN OVERVIEW, WITH COMMENTS ON FRESHWATER REQUIREMENTS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: H. L. Jerling --- , , South AfricaThe Mhlathuze estuary in its present form was established during construction of the Richards Bay harbour during the early 1970s. This paper summarises available data on the zooplankton community as part of a study on the freshwater requirements of the... -
Physical determinants of the distribution and abundance of the burrowing ocypodid crab Paratylodiplax blephariskios Stebbing in the St. Lucia and Mhlathuze estuaries, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RK Owen AT Forbes DP Cyrus SE PiperThe burrowing ocypodid crab, Paratylodiplax blephariskios, is endemic to the southeast coast of southern Africa where it forms an important component of the estuarine benthic fauna in muddy substrata. Two estuaries in KwaZulu-Natal, namely St. Lucia and the Mhlathuze, were... -
Phytoplankton/protozoan dynamics in the Nyara Estuary, a small temporarily open system in the Eastern Cape (South Africa)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DR Walker R Perissinotto RPA BallyMost estuarine studies in South Africa have focused on larger estuaries, while numerous, smaller, temporarily open estuaries have received little research attention. This study examines the phytoplankton distribution in relation to physical and chemical variables through a quasi-seasonal cycle (from... -
Stable isotope (∂13C) composition of the food web of the temperate Kariega estuary (Eastern Cape)
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW FronemanStable isotope (∂13C) composition of the food web in the temperate Kariega estuary in summer and winter was analysed to determine the trophic relationships between 19 taxa. There was no seasonality in the stable isotope ratios of the dominant producers... -
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... -
Changes in the distribution of emergent aquatic plants in a brackish South African estuarine-lake system
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: IA RussellVegetation mapping in the Wilderness Lakes indicated that, between 1975 and 1997, prominent increases occurred in the distribution of the mapping units Phragmites australis (53.9ha; +53%), grass or fields (23.1ha; +35%) and scrub or trees (12.2ha; +45%). Over the same... -
The distribution and habitat in the Knysna Estuary of the endemic South African mudsnail Hydrobia knysnaensis and the influence of intraspecific competition and ambient salinity on its abundance
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Rsk BarnesThe typical habitat of the rare, endemic South African mudsnail Hydrobia knysnaensis is the leaves of upper-shore Zostera capensis within high-salinity salt-marsh pools and channels. In the Knysna estuarine system, it is the numerically dominant member of a guild of... -
Zooplankton community changes in Nhlabane estuary, South Africa, induced by man-made structures and drought
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HL JerlingThe Nhlabane estuary and coastal lake system has suffered a number of man-made impacts since 1977, when the lake and estuary were separated by the construction of a barrage. More recent man-made events included the construction of temporary sand walls,... -
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... -
Status of the estuarine fish fauna in the St Lucia Estuarine System, South Africa, after 30 months of mouth closure
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Digby Cyrus Leon VivierThe Lake St Lucia Estuarine System, South Africa, has been under pressure due to recent drought conditions, which led to extreme low lake levels, hypersaline conditions and closure of the mouth. The estuary mouth closed in June 2002 and has... -
Fish breeding in, and juvenile recruitment to, the St Lucia Estuarine System under conditions of extended mouth closure and low lake levels
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Digby Cyrus Leon VivierOngoing drought conditions along the northern coast of KwaZulu-Natal resulted in the St Lucia Estuary mouth closing, and to evaporation leading to extremely low lake levels and the development of hypersaline conditions in most parts of the system. The mouth... -
The distribution and abundance of the endangered Knysna seahorse Hippocampus capensis (Pisces: Syngnathidae) in South African estuaries
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JacquelineF Lockyear Thomas Hecht Horst Kaiser PeterR TeskeThe occurrence, distribution and abundance of the endangered Knysna seahorse Hippocampus capensis in 10 estuaries on South Africa's warm temperate south coast, were investigated. Seahorses were found only in the Knysna, Swartvlei and Keurbooms estuaries. Sex ratios were even and,... -
Salinity tolerance of the burrowing ocypodid crab, Paratylodiplax blephariskios, in the St. Lucia and Mhlathuze estuaries, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RK Owen --- Department of Zoology, South Africa AT Forbes --- , South AfricaThe ocypodid crab, Paratylodiplax blephariskios, is endemic to the southeast coast of southern Africa where it forms an important component of the estuarine benthic fauna in muddy substrata. The St. Lucia and Mhlathuze estuaries are two of the largest estuaries... -
Seasonal changes in selected physico-chemical and biological variables in the temporarily open/closed Kasouga estuary, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW Froneman --- Coastal Research Unit, Department of Zoology and Entomology, South AfricaSeasonal changes in selected physico-chemical (temperature, salinity and turbidity) and biological (chlorophyll-a (chl-a), microphytobenthos and microheterotrophs) variables were measured at 7–9 day intervals for a period of 14 months in the temporarily open/closed Kasouga estuary. In addition, zooplankton biomass was... -
Initial characterisation of the mesozooplankton community of the Mfolozi– Msunduzi estuarine system, KwaZulu-Natal, South Africa, during a low-flow period
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HL Jerling --- Coastal Research Unit of Zululand, Department of Zoology, South Africa L Vivier --- Coastal Research Unit of Zululand, Department of Zoology, South Africa DP Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa RK Owen --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaThe mesozooplankton of the Mfolozi and Msunduzi estuaries, which share a combined mouth, was sampled twice per year during a two-year period of relatively low river flow. Samples were collected during March, after the rainy season when the estuary mouth... -
Characterisation of the mesozooplankton community in response to contrasting estuarine salinity gradients in the Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: TH Wooldridge --- Department of Zoology, South AfricaStructure and pattern of mesozooplankton in three tidal estuaries experiencing contrasting salinity gradients were investigated. In the Kariega Estuary, where freshwater inflow was persistently low with little variation in flow, salinity values exceeded 28–30 for long periods (years) throughout the... -
Ecological status and role of the Mfolozi–Msunduzi estuarine system within the iSimangaliso Wetland Park, a World Heritage Site on the south-east coast of South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DP Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa L Vivier --- Coastal Research Unit of Zululand, Department of Zoology, South Africa RK Owen --- Coastal Research Unit of Zululand, Department of Zoology, South Africa HL Jerling --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaThe original structure and functioning of the historical Mfolozi–St Lucia estuarine system are described and anthropogenic impacts, which resulted in the Mfolozi and Msunduzi rivers being separated from the St Lucia Estuary and having their own combined mouth to the... -
Aspects of population dynamics and feeding by piscivorous birds in the intermittently open Riet River estuary, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PW Froneman --- Department of Zoology and Entomology, South Africa JD Blake --- Department of Zoology and Entomology, South Africa P Hulley --- Department of Zoology and Entomology, South AfricaAspects of the population dynamics and feeding activity of piscivorous birds in the small (c. 5 ha) intermittently open Riet River estuary, on the south-eastern coastline of South Africa, were investigated monthly from August 2005 to July 2006. A total... -
Reeds as indicators of nutrient enrichment in a small temporarily open/ closed South African estuary
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: LRD Human --- Department of Botany, South Africa JB AdamsThis study investigated the use of δ15N levels in Phragmites australis reeds as an indicator of nutrient input into the small temporarily open/closed East Kleinemonde Estuary, Eastern Cape, South Africa. Nutrient (NH4 and SRP) concentrations decreased from the bank towards... -
Diet of the demersal feeding Leiognathus equula in the Mfolozi–Msunduzi estuarine system, South Africa, in response to an impoverished macrobenthic invertebrate community
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JBB Nhleko --- Coastal Research Unit of Zululand, Department of Zoology, South Africa DP Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South Africa L Vivier --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaLeiognathus equula, a species generally regarded as a zoobenthic feeder, was the most abundant fish species sampled in the Mfolozi–Msunduzi estuarine system in 2008–2010, despite the zoobenthos in this system being impoverished. Four dietary assessment methods all confirmed that its... -
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... -
Activity and feeding of Dotilla fenestrata (Brachyura: Ocypodidae) in a warm, temperate South African estuary
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: C Bulcao --- Department of Zoology and Entomology, South Africa AN Hodgson --- Department of Zoology and Entomology, South AfricaThe activity of and consumption of organic material by the sand-bubbler crab Dotilla fenestrata was studied over neap and spring tides on a sheltered sand bank close to the mouth of the warm, temperate Kowie Estuary, South Africa. Crabs emerged... -
Spatio-temporal variability of surface water quality parameters in a South African estuarine lake system
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: IA Russell --- , South AfricaLong-term (20+ years) water quality datasets for estuaries are rare, especially for smaller systems. Monitoring of salinity, temperature, pH, dissolved oxygen and turbidity has been undertaken since 1991 in the intensively utilised, modified, and managed temporarily open/closed Touw Estuary and... -
Response of mangroves to drought and non-tidal conditions in St Lucia Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SCL Hoppe-Speer --- Botany Department, South Africa JB Adams --- Botany Department, South Africa A Rajkaran --- Botany Department, South AfricaThe effect of a prolonged closed-mouth state on the condition of mangrove habitats was studied in May 2010 at St Lucia Estuary, KwaZulu-Natal. The mouth had been closed to the sea since 2002 as a result of artificial mouth closure... -
Dissolved Oxygen Characteristics of the Gamtoos Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M. W. Pearce E. H. SchumannThe fall and recovery of dissolved oxygen (DO) is documented throughout the Gamtoos Estuary, South Africa during dry conditions and following light and heavy rainfall over a 13-month period from November 1992 to November 1993. Hypoxic conditions generally occurred in... -
Assessment of the Linefishery in Two Urban Estuarine Systems In Kwazulu-natal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P. Pradervand L. E. Beckley B. Q. Mann P. V. RadebeThe recreational linefisheries in Durban Harbour and the Mgeni Estuary were surveyed using roving creel and access-point surveys during the period January–December 2000. In total, 3 351 shore-anglers and 652 boat-anglers were checked for catch-and-effort information, and 432 shore-anglers were... -
Physical Factors Regulating Macrobenthic Community Structure on a South African Estuarine Flood-tidal Delta
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M. L. Bursey T. H. WooldridgeMultivariate techniques were used to identify environmental parameters affecting macrobenthic communities on the flood-tidal delta of the Nahoon Estuary and adjacent beach near East London on the south-east coast of South Africa. Water content of sediments, temperature and exposure were... -
The Zooplankton Community of the Mhlathuze (Richards Bay) Estuary: Two Decades After Construction of the Harbour
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: H. L. JerlingThe Mhlathuze (Richards Bay) Estuary on the KwaZulu-Natal coast, South Africa, was substantially altered during the early 1970s, when it was divided into two separate systems. The northern section was developed into a deep-water harbour, whereas the southern part was... -
A telemetry experiment on spotted grunter Pomadasys commersonnii in an African estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SE Kerwath A Götz PD Cowley WHH Sauer C AttwoodThe feasibility of using telemetry equipment to study the movements of estuarine-associated fish in South Africa was investigated by conducting a tracking experiment on spotted grunter Pomadasys commersonnii in the East Kleinemonde Estuary. The telemetry equipment comprised two VEMCO V8... -
Geomorphological and managerial implications of fish trapping in the Kosi Bay Estuary, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AN Green GG Garland R UkenThe tidal basin of the Kosi Bay lagoonal-lacustrine complex is dominated by fish traps that line the intertidal and subtidal environments. These have been considered significant sediment sinks, responsible for transformation of parts of the system from subtidal and intertidal... -
Variability in estuarine water temperature gradients and influence on the distribution of zooplankton: a biogeographical perspective
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: TH Wooldridge --- Department of Zoology, South Africa SHP Deyzel --- , South AfricaStructure and variability of water temperature gradients and potential influence on distribution of two tropical zooplankters (the mysid Mesopodopsis africana and the copepod Acartia natalensis) and their temperate congenerics (M. wooldridgei and A. longipatella) was investigated over a 10-year period... -
Plant traits and spread of the invasive salt marsh grass, Spartina alterniflora Loisel., in the Great Brak Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JB Adams --- Department of Botany, South Africa A Grobler --- Department of Botany, South Africa C Rowe --- Department of Botany, South Africa T Riddin --- Department of Botany, South Africa TG Bornman --- , South Africa DR Ayres --- Evolution and Ecology, USASpartina alterniflora Loisel., widely recognised as an aggressive invader of estuaries and salt marshes around the world, was discovered growing in the temporarily open/closed Great Brak Estuary on the southern Cape coast of South Africa in 2004. This is the... -
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... -
Composition, abundance, distribution and seasonality of larval fishes in the Mngazi Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: P Pattrick NA Strydom TH WooldridgeWe investigated the larval fish assemblage in the intermittently-open Mngazi Estuary, in the subtropical/warm-temperate biogeographic boundary region of South Africa. Larvae were collected by means of boat-based plankton tows in summer and winter for a period of three years between... -
Trophic interactions amongst the plankton in the temporarily open/closed East Kleinemonde Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: EL Allan PW FronemanThe trophic interactions between bacteria, phytoplankton, nanoflagellates (2–20 μm), microzooplankton (20–200 μm) and mesozooplankton (200–2 000 μm) were investigated in winter and summer in the temporarily open/closed East Kleinemonde Estuary, Eastern Cape. During winter the phytoplankton community was dominated by... -
Bioaccumulation of platinum group metals in dolphins, Stenella sp., caught off Ghana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: DK EssumangPlatinum group metals (PGMs) concentrations were measured in the tissues= of dolphins (Stenella sp.) caught along the Ghanaian coastline. Tissues from specimens caught by fishermen from Dixcove, western Ghana, were analysed in 2006 for palladium (Pd), platinum (Pt) and rhodium... -
Zooplankton composition, abundance and distribution in selected south and west coast estuaries in South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PH Montoya-Maya --- Department of Ichthyology and Fisheries Science, South Africa NA Strydom --- , South AfricaIn order to contribute to the understanding of estuarine zooplankton dynamics in cool-temperate systems, zooplankton samples were collected by plankton tows, using two modified WP2 nets, in nine estuaries on the south and west coasts of South Africa, seasonally between... -
Abundance, recruitment and residency of two sparids in an intermittently open estuary in South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: NC James PD Cowley AK WhitfieldThe recruitment of distinct year-class cohorts in two sparid species, Rhabdosargus holubi and Lithognathus lithognathus, were linked to records of daily mouth state in the intermittently open East Kleinemonde Estuary, South Africa, between 1995 and 2006. L. lithognathus only recruited... -
The zooplankton community of Richards Bay Harbour and adjacent Mhlathuze Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HL JerlingDuring construction of the current Richards Bay Harbour in the early 1970s, the original shallow Mhlathuze Estuary was divided into two separate systems: a new estuary and a deep-water harbour. This study compares the zooplankton communities of the current systems... -
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... -
Evidence of recovery of the linefishery in the Berg River Estuary, Western Cape, South Africa, subsequent to closure of commercial gillnetting
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Hutchings BM Clark LJ Atkinson CG AttwoodA total of 248 roving creel surveys along the length of the Berg River Estuary, in the Western Cape, South Africa, recorded 626 shore-angler and 88 boat-angler outings over the period December 2002–November 2005. Catch-and-effort information was obtained from catch... -
Catching and tracking the world's largest Zambezi (bull) shark Carcharhinus leucas in the Breede Estuary, South Africa: the first 43 hours
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: ME McCord SJ LamberthThe Zambezi or bull shark Carcharhinus leucas is a large, predatory shark that occurs in warm-temperate, tropical and subtropical coastal and estuarine systems worldwide. To confirm reports of Zambezi sharks in the Breede Estuary on the south-west coast of South... -
Prawn community structure in the subtropical Mfolozi–Msunduzi estuarine system, KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: SJ Collocott --- Coastal Research Unit of Zululand, Department of Zoology, South Africa L Vivier --- Coastal Research Unit of Zululand, Department of Zoology, South Africa DP Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaThe life cycles of many marine and freshwater prawn species are closely associated with estuarine habitat. Here, the prawn community of the Mfolozi–Msunduzi estuarine system is described and the system's potential as an alternative nursery for prawns during prolonged closure... -
Potential impacts of alternative regulatory interventions on the recreational value of angling on the Breede River estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JK Turpie --- Environmental-Economics Policy Research Unit, South Africa JR Goss --- Anchor Environmental Consultants, Silverwood Close, South AfricaThis study investigated the support for, and potential impacts of, alternative management measures to address declining fish stocks in the Breede River estuary. A survey of residents and visitors was carried out during 2011–2012. Angling was the most important attraction... -
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... -
Predation by introduced largemouth bass Micropterus salmoides on indigenous marine fish in the lower Kowie River, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: ML Magoro --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa L Carassou --- Department of Zoology and Entomology, South AfricaThe predatory impact of introduced largemouth bass Micropterus salmoides on the juveniles of estuary-associated indigenous marine fish species in the lower Kowie River and estuary headwaters was investigated in 2012–2013. Stomach contents and stable isotope analyses were employed to assess... -
Description of larval fish composition, abundance and distribution in nine south and west coast estuaries of South Africa
Item type: Journal Article • Journal: African Zoology • Authors: P. H. Montoya-Maya --- Department of Ichthyology and Fisheries Science, South Africa N. A. Strydom --- South African Institute for Aquatic Biodiversity, South AfricaThe composition, abundance and distribution of larval fishes from nine south and west coast estuaries from South Africa was investigated by plankton tow once per season between June 2003 and March 2004. A total of 49 274 early stage fishes... -
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... -
Invasive alien freshwater fishes in the Wilderness Lakes System, a wetland of international importance in the Western Cape Province, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: A. A. Olds --- Department of Ichthyology and Fisheries Science, South Africa M. K. S. Smith --- South African National Parks, Scientific Services, South Africa O. L. F. Weyl --- South African Institute for Aquatic Biodiversity, South Africa I. A. Russell --- South African National Parks, Scientific Services, South AfricaThe Wilderness Lakes System incorporates a RAMSAR listed wetland. Previous ichthyological surveys reported three invasive freshwater fishes; Oreochromis mossambicus (Mozambique tilapia), Gambusia affinis (mosquitofish) and Micropterus salmoides (largemouth bass) from this system. To assess the status of these alien fishes,... -
Macrofaunal community structure in the littoral zone of a freshwater-deprived, permanently open Eastern Cape estuary
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 AfricaSpatial patterns in the macrofauna community structure within four distinct zones of the permanently open, freshwater-deprived Kariega Estuary on the southeastern coastline of southern Africa were investigated in March–May 2010. The zones within the littoral zone comprised a band of... -
Composition, abundance, distribution and seasonality of larval fishes in the Sundays Estuary, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: K. Sutherland --- Department of Zoology, South Africa N.A. Strydom --- Department of Zoology, South Africa T.H. Wooldridge --- Department of Zoology, South AfricaThe larval fish assemblage was studied in the permanently open Sundays Estuary on the southeast coast of South Africa. Seasonal samples were collected between winter 2007 and autumn 2009 at eight sites along the estuary by means of boat-based plankton... -
Influence of mouth status on population structure of southern African endemic estuarine-spawning ichthyofauna in a temperate, temporarily open/closed estuary
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GP Tweddle --- Coastal Research Unit of Zululand, Department of Zoology, South Africa PW Froneman --- Department of Zoology and Entomology, South AfricaThe effect of mouth status on the population structure of three endemic estuarine-spawning fish species was assessed using seine nets from November 2005 to October 2007 in the temporarily open/closed Mpekweni Estuary, Eastern Cape, South Africa. Collectively, these three species... -
Characteristics and landcover of estuarine boundaries: implications for the delineation of the South African estuarine functional zone
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: DA Veldkornet --- Department of Botany, South Africa JB Adams --- Department of Botany, South Africa L van Niekerk --- Department of Botany, South AfricaThis study investigated whether the current lateral boundary for estuaries in South Africa, i.e. the estuarine functional zone (EFZ), includes all estuarine habitats. The EFZ covers 173 930 ha in 304 estuaries/outlets nationally. Field surveys and analysis of available aerial... -
Diversity of benthic macrofauna of the flood-tidal delta of the Nahoon Estuary and adjacent beach,South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Mary Bursey --- East London Museum, South Africa Tris Wooldridge --- Zoology Department, South AfricaMacrobenthos of the Nahoon estuarine flood-tidal delta was surveyed to determine species composition, distribution and abundance; establish possible patterns in community structure and compare assemblages with those of adjacent sandy beach and lower estuary. Macrozoobenthos retained by a 1 mm... -
The role of estuarine type in characterizing early stage fish assemblages in warm temperate estuaries, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: N.A. Strydom --- Department of Ichthyology and Fisheries Science, South Africa A.K. Whitfield --- South African Institute for Aquatic Biodiversity, South Africa T.H. Wooldridge --- Department of Zoology, South AfricaAssemblages of early stage fishes (larval and early juvenile stages) were investigated and compared in seven permanently open and five intermittently open estuarine systems on the warm temperate Eastern Cape coast of South Africa. Estuarine type, by virtue of mouth... -
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... -
Larval fish dynamics in the Nxaxo-Ngqusi Estuary Complex in the warm temperate–subtropical transition zone of South Africa
Item type: Journal Article • Journal: African Zoology • Authors: R.J. Wasserman --- Department of Zoology, U.S.A N.A. Strydom --- Department of Zoology, U.S.A T.H. Wooldridge --- Department of Zoology, U.S.AThe larval fish assemblage was investigated in the permanently open Nxaxo-Ngqusi Estuary Complex, situated in the subtropical–warm temperate biogeographic boundary zone of South Africa. Larval and early juvenile fishes were collected in summer and winter of 2007 and 2008 using... -
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... -
In vitro screening for endocrine disruptive activity in selected South African harbours and river mouths
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JC Truter --- Department of Botany and Zoology, South Africa JH van Wyk --- Department of Botany and Zoology, South Africa BK Newman --- Coastal Systems Research Group, Natural Resources and the Environment, South AfricaVarious waterborne anthropogenic contaminants disrupt the endocrine systems of wildlife and humans, targeting reproductive pathways, among others. Very little is known, however, regarding the occurrence of endocrine disruptive activity in South African freshwater ecosystems, and coastal ecosystems have not been... -
Mytilus galloprovincialis (Mollusca: Bivalvia) in a warm-temperate South African estuarine embayment
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Pollard --- Department of Zoology and Entomology, Knysna Basin Project, South Africa AN Hodgson --- Department of Zoology and Entomology, Knysna Basin Project, South AfricaThe distribution, population structure, condition and gonad indices, and the attachment strengths of the invasive Mediterranean mussel Mytilus galloprovincialis are described from the Knysna Estuary, South Africa. Mussels were found in the rocky intertidal at the mouth of the estuary... -
Long-term physical, chemical and biological changes in a small, urban estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Viskich --- Department of Biological Sciences and Centre for Invasion Biology, South Africa CL Griffiths --- Department of Biological Sciences and Centre for Invasion Biology, South Africa C Erasmus --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, South Africa S Lamberth --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, South AfricaThe Diep River estuary, a small estuary in suburban Cape Town, South Africa, has been subject to disturbance for centuries. Several earlier studies have documented conditions in the system, providing baselines against which to measure more recent changes. This study:... -
Suspended silt and salinity tolerances of the first zoeal stage of the fiddler crab Uca annulipes (Decapoda: Brachyura) and why marine connectivity is essential to the survival of the species
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N Peer --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa NAF Miranda --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, South AfricaFiddler crabs (Uca spp.) undergo the zoeal stage of development in open-ocean waters, where they experience stable salinity levels, low turbidity and reduced predation. The St Lucia estuarine system has undergone many geomorphological changes, both natural and anthropogenic, and the... -
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... -
Mesozooplankton community structure changes in the Mfolozi–Msunduzi estuarine system, South Africa, during contrasting river flow conditions
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: HL Jerling --- Coastal Research Unit of Zululand, Department of Zoology, South Africa DP Cyrus --- Coastal Research Unit of Zululand, Department of Zoology, South AfricaThe Mfolozi–Msunduzi estuarine system is subject to periodic dry and wet cycles, with subsequent changes in the abiotic and biotic characteristics of the system. The aim of the current study was to compare its mesozooplankton composition during relatively dry and... -
Seasonal population dynamics and energy consumption by waterbirds in a small temperate estuary
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Jeffrey W Hean --- Department of Zoology and Entomology, South Africa Adrian JFK Craig --- Department of Zoology and Entomology, South Africa Nicole B Richoux --- Department of Zoology and Entomology, South AfricaSimple measures of population dynamics and energy consumption can provide baseline information on the role of consumers in food webs, particularly for cryptic or highly-mobile species of waterbirds. We provide estimates of the seasonal population dynamics and energy consumption of... -
Philopatry and dispersal of juvenile leervis Lichia amia (Teleostei: Carangidae) tagged in a warm-temperate South African estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Murray --- South African Institute for Aquatic Biodiversity, South Africa P Cowley --- South African Institute for Aquatic Biodiversity, South Africa A-R Childs --- Department of Ichthyology and Fisheries Science, South Africa R Bennett --- South African Institute for Aquatic Biodiversity, South AfricaUnderstanding and characterising movement and area-use patterns of fishes within estuaries, as well as understanding the degree of connectivity between estuaries and the marine environment, can provide important insights into a species’ ecology, which is fundamental for effective management and... -
Space use by Rhabdosargus holubi in a southern African estuary, with emphasis on fish movements and ecosystem connectivity
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GN Grant --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa PD Cowley --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa RH Bennett --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa TS Murray --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaTwenty-one juvenile Cape stumpnose Rhabdosargus holubi (140–190 mm fork length) were tagged with internal acoustic transmitters in the lower, middle and upper reaches of the Kowie Estuary, South Africa. The movements of each fish were continually monitored from October 2014... -
Fish recruitment into a South African temporarily open/closed temperate estuary during three different hydrological mouth phases
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GP Tweddle --- Department of Zoology, South Africa PW Froneman --- Department of Zoology and Entomology, South AfricaQuantitative recruitment of ichthyofauna into a South African temporarily open/closed estuary (TOCE) was investigated during three distinct hydrological phases: closed overwash, open outflow and tidal mouth conditions. Maximum recruitment densities occurred during outflow conditions and declined when the system became... -
Eelgrass beds and bare substrata – sparid and mugilid composition in contrasting littoral estuarine habitats
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Pollard --- Department of Zoology and Entomology, South Africa AN Hodgson --- Department of Zoology and Entomology, South Africa HM Kok --- Port Elizabeth Museum, South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaSeagrass beds serve as nursery grounds for many fish species and often play an important role in the juvenile stages of economically and recreationally important fishes. The eelgrass Zostera capensis is the dominant submerged macrophyte in permanently open South African... -
Microfossils in surface sediments of brackish waters on the west coast of South Africa and their palaeoecological implications
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: S Fürstenberg --- Institute of Geosciences, Friedrich Schiller University Jena, Germany N Gründler --- Institute of Geosciences, Friedrich Schiller University Jena, Germany S Meschner --- Institute of Geosciences, Friedrich Schiller University Jena, Germany P Frenzel --- Institute of Geosciences, Friedrich Schiller University Jena, GermanyA faunistic survey covering 25 sites in estuaries, coastal lakes and ponds along the west coast of South Africa between the Cape of Good Hope in the south and the Olifants River in the north was carried out in May... -
Vertical distribution of living mangrove foraminifera from KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KL Strachan --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South Africa TR Hill --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South Africa JM Finch --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South AfricaModern foraminiferal assemblage zones can be used to reconstruct palaeo sea levels when applied to fossil foraminifera down a sediment core. Previous intertidal foraminiferal studies have predominantly focused on assemblages in surface sediments (0–1 cm), with the rationale that surface... -
A multimetric-index approach using fisheries data to assess fish assemblage structure in relation to salinity gradient in a tropical West African estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Kantoussan --- Université Gaston Berger de Saint-Louis, Senegal JM Ecoutin --- Institut de Recherche pour le Développement (IRD), France R Laë --- Institut de Recherche pour le Développement (IRD), France OT Thiaw --- Institut Universitaire de Pêche et d’Aquaculture (IUPA), Université Cheikh Anta Diop de Dakar, Senegal L Tito de Morais --- Institut de Recherche pour le Développement (IRD), FranceThis study examines the effects of increasing salinity on fish assemblage structure in the Casamance Estuary, Senegal, using a series of indices. The study data were derived from commercial fishery surveys conducted between April and July 2005. Analysis of within-trophic-group... -
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... -
Long-term physico-chemical and faunal changes in a small, rural South African estuary
Item type: Journal Article • Journal: African Zoology • Authors: M Kajee --- Department of Biological Sciences and Centre for Invasion Biology, South Africa CL Griffiths --- Department of Biological Sciences and Centre for Invasion Biology, South Africa SJ Lamberth --- Fisheries Management, Department of Agriculture, South AfricaThe Palmiet Estuary is a small, rural estuary in the Western Cape that only closes briefly during dry summers. The system was previously surveyed during 1979 to 1980 and we repeated the survey in April 2015 (mouth closed) and September... -
A tale of two habitats: preliminary comparison of fish abundance and diversity between saltmarsh- and mangrove-dominated creeks in the Nahoon Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Keur --- Department of Biodiversity and Conservation Biology, Faculty of Natural Science, South Africa N James --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa A Rajkaran --- Department of Biodiversity and Conservation Biology, Faculty of Natural Science, South AfricaA preliminary assessment of abundance and richness of fishes utilising saltmarsh and mangrove habitats in the Nahoon Estuary, situated on the eastern coast of South Africa, was undertaken during July 2017. The structural composition and complexity of the two habitats... -
The influence of prolonged drought and anthropogenic impact reversal on fish community structure and ecosystem state cycling of Lake St Lucia, Africa’s largest estuarine lake
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: D Cyrus --- Coastal Research Unit of Zululand, South Africa Q Schutte --- Coastal Research Unit of Zululand, South Africa L Vivier --- Coastal Research Unit of Zululand, South AfricaHistorically, the St Lucia Estuarine Lake System and uMfolozi River joined via an estuarine bay before exiting to the sea. In 1952, separate mouths were created, because of sediment problems originating from the uMfolozi River. During the 2004 drought, the... -
Abiotic and biotic responses to the 2016/2017 restoration project at the St Lucia Estuary mouth, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: S Jones --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa NK Carrasco --- School of Life Science, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa C Fox --- Ezemvelo KwaZulu-Natal Wildlife, St Lucia Estuary, South AfricaThe St Lucia Estuary is the largest estuarine lake in Africa and has been heavily impacted by anthropogenic activities, which include a history of human-induced sediment loading and separation in the 1950s of the originally common St Lucia Estuary-uMfolozi River... -
Mangrove colonisation of the Mlalazi Estuary, South Africa: a response to artificial breaching
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RH Taylor --- Hydrology Department, South AfricaThe Mlalazi Estuary has 40 ha of mangroves, but before the 1930s there were none. The purpose of this study is to understand why this change occurred, and how the understanding thus gained can provide ecological information that will help... -
A socio-ecological systems approach towards future research for the restoration, conservation and management of southern African estuaries
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: JB Adams --- DST/NRF Research Chair in Shallow Water Ecosystems, South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa L Van Niekerk --- DST/NRF Research Chair in Shallow Water Ecosystems, South AfricaThis Reflections article highlights the growing pressures that southern African estuaries are experiencing in the Anthropocene, as identified by the research presented in this Special Medal Issue. Estuaries are exposed to multiple stressors, and their responses to climate change are... -
Mapping subtidal estuarine habitats with a remotely operated underwater vehicle (ROV)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Wasserman --- Botany Department, DST/NRF Research Chair in Shallow Water Ecosystems, South Africa L Claassens --- Department of Zoology and Entomology, South Africa JB Adams --- Botany Department, DST/NRF Research Chair in Shallow Water Ecosystems, South AfricaSubtidal habitats have not yet been accounted for in habitat maps of South African estuaries. In this study, a novel method for mapping subtidal estuarine habitats, using a remotely operated underwater vehicle (ROV) piloted from a boat, was developed and... -
Spatial variation of nutrients and primary productivity in the Rufiji Delta mangroves, Tanzania
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Minu --- , Tanzania J Routh --- , Sweden JF Machiwa --- , Tanzania S Pamba --- , TanzaniaDeterminations of spatial and temporal variations in organic matter and nutrient dynamics in water and sediments are crucial for understanding changes in aquatic bodies. In this study, we (i) determine the spatial dynamics of dissolved inorganic nutrients, during the transition... -
Diel and tidal periodicity in the responses of early life stages of marine fishes to an estuary opening event in temperate South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Y Kisten --- , South Africa NA Strydom --- , South AfricaEarly life stages of fish were monitored in a breach channel during an opening event of the temporarily open/closed East Kleinemonde Estuary. For comparison, early life stages were also collected in the surf zone and estuary mouth region before, during... -
Settlement of the invasive mussel Mytilus galloprovincialis in a warm temperate estuarine embayment in South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: J Radloff --- , South Africa AN Hodgson --- , South Africa L Claassens --- , South AfricaMytilus galloprovincialis, a globally successful marine alien invasive species, occupies all artificial hard substrata in the embayment of the Knysna estuary, South Africa. The current study compared temporal and spatial settlement patterns of M. galloprovincialis within this environment. Settlement was... -
Salt marsh erosion in a microtidal estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Riddin --- , South Africa JB Adams --- , South AfricaSalt marshes protect estuary banks from erosion by acting as buffers between marine and terrestrial environments. Residents living near the Breede River estuary, Western Cape Province, South Africa, raised concerns about ongoing erosion evident at Groenpunt, the main salt marsh... -
Tidal influence on fish faunal occurrence and distribution in an estuarine mangrove system in Ghana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NK Asare --- , Ghana JL Javier --- , United StatesThis study assessed the effects of tidal stages and habitat conditions on nekton assemblage and distribution in the Kakum River estuarine mangrove system in the Central Region of Ghana. Teleosts and crustaceans were sampled using pole seine and cast net... -
Restoration of South African estuaries: successes, failures and the way forward
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Claassens --- Rhodes University, South Africa JB Adams --- Institute for Coastal & Marine Research, Nelson Mandela University, South Africa NM de Villiers --- Rhodes University, South Africa J Wasserman --- Institute for Coastal & Marine Research, Nelson Mandela University, South Africa AK Whitfield --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaMajor threats to South African estuaries include freshwater flow alterations, urbanisation, habitat transformation, deteriorating water quality, increased biological invasions and resource over-exploitation. Although South African estuary restoration is in its infancy, important lessons have been learnt through past efforts undertaken... -
Eelgrass Zostera capensis populations in KwaZulu-Natal, South Africa, harbour distinct genomic signals despite limited geographical distance
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SE Smit --- Stellenbosch University, South Africa R Henriques --- University of Pretoria, South Africa M Jackson --- Stellenbosch University, South Africa R Taylor --- , South Africa L Vivier --- University of Zululand, South Africa S von der Heyden --- Stellenbosch University, South AfricaSeagrasses are threatened by anthropogenic stressors and climate change, with numerous population declines reported. In South Africa, the eelgrass Zostera capensis is restricted to estuarine environments and has a disjunct distribution and declining status. With the majority of the distribution... -
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... -
Multi-method approach identifies a South African estuary as an important elasmobranch habitat and potential nursery ground
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Elston --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa TS Murray --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaElasmobranchs play important ecological roles but are highly threatened. Understanding their habitat use and abundance is crucial for the management and conservation of these species and their habitats. While some species are known to use estuaries as vital habitats (e.g... -
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... -
The use and protection of water resources in the uThukela River Catchment, South Africa: a review of its past, present and future
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: M Wade --- University of Mpumalanga, South Africa GC O’Brien --- Gulbali Institute, Charles Sturt University, Australia G Jewitt --- IHE Delft Institute for Water Education, the NetherlandsSouth Africa is a water-stressed country and therefore the quantity and quality of the water resources are very important. The uThukela River is one of South Africa’s largest rivers and is a critical component of water resource utilisation in South... -
Lumbrineris magalhaensis Kinberg, 1865 (Annelida: Lumbrineridae) revealed as two indigenous species in South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Adri van Niekerk --- Stellenbosch University, South Africa Jyothi Kara --- Iziko South African Museum, South Africa Arturo Alvarez-Aguilar --- Stellenbosch University, South Africa Carol A Simon --- Stellenbosch University, South AfricaLumbrineris magalhaensis Kinberg, 1865 (Annelida: Lumbrineridae) is a marine polychaete worm that was first described from the Magellan Strait, Chile; thereafter it was also reported in sub-Antarctic, temperate and tropical regions, where it was likely misidentified. In South African waters,... -
The movements of adult leerfish Lichia amia in the Breede Estuary, Western Cape, South Africa: insights from acoustic telemetry
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: WM Kilian --- Rhodes University, South Africa TS Murray --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa JD Filmalter --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa PD Cowley --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa TF Næsje --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa RJ Wasserman --- Rhodes University, South AfricaLeerfish Lichia amia inhabit estuaries as juveniles before moving between estuaries and the marine environment as sub-adults and adults. While adults remain mostly in the marine environment, philopatry has been observed, with individuals returning to areas previously used, including estuaries... -
Assessing the thermal tolerance of a cosmopolitan eurythermal species, the flathead mullet Mugil cephalus
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: DL Mukhari --- Rhodes University, South Africa A-R Childs --- Rhodes University, South Africa BA Ziko --- Rhodes University, South Africa TS Murray --- Rhodes University, South AfricaWater temperature is a key abiotic factor affecting fish physiology, behaviour and distribution, with fluctuations impacting species assemblages and habitat use. The flathead mullet Mugil cephalus is a eurythermal species with a cosmopolitan distribution across tropical, subtropical and temperate coastal... -
Individual variability in the thermal limits of juvenile dusky kob Argyrosomus japonicus from a permanently open estuary
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Frachet --- Rhodes University Department of Ichthyology and Fisheries Sciences, South Africa A-R Childs --- Rhodes University Department of Ichthyology and Fisheries Sciences, South Africa AC Winkler --- Rhodes University Department of Ichthyology and Fisheries Sciences, South Africa MW Farthing --- Rhodes University Department of Ichthyology and Fisheries Sciences, South Africa CD Hempel --- Rhodes University Department of Ichthyology and Fisheries Sciences, South Africa WM Potts --- Rhodes University Department of Ichthyology and Fisheries Sciences, South AfricaGlobally, fish are facing the pressure of increasing thermal variability, which challenges the physiological capacity and resilience of species at the level of the individual, population and community. As transition zones, estuarine ecosystems are becoming increasingly thermally dynamic, which affects... -
Spatiotemporal shape variation in sagittal otoliths of spotted grunter Pomadasys commersonnii in South African estuaries
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: V Coetzee --- Department of Biological Sciences, University of Cape Town, South Africa S Kerwath --- Department of Biological Sciences, University of Cape Town, South Africa S Lamberth --- Department of Forestry, Fisheries and the Environment (DFFE), South Africa D Parker --- Department of Biological Sciences, University of Cape Town, South AfricaThe morphological structure of fish otoliths is under dual regulation by genetic and environmental factors, and has been successfully used to aid stock delineation. This study examined whether differences in sagittal otolith shape outlines could be used to delineate potential... -
Will I survive? Assessing the thermal tolerance of an estuary-dependent mugilid, Chelon dumerili, in a changing climate
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BA Ziko --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa AR Childs --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa DL Mukhari --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa TS Murray --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaDetermining the thermal tolerance limits of fishes is crucial for understanding their persistence in the face of anthropogenic climate change. This study used dynamic critical thermal assays to determine the upper (CTmax) and lower (CTmin) critical thermal limits of an...