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Interaction between Cape hake spawning and the circulation in the northern Benguela upwelling ecosystem
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: S. Sundby A. J. Boyd L. Hutchings M. J. O'Toole K. Thorisson A. ThorsenCape hake in Namibian waters are demersal and mesopelagic spawners, spawning peaking offshore between 100 and 400 m deep, depending on local environmental conditions. The cross-shelf circulation, low-oxygen layers and mesoscale gyres are three important environmental factors influencing hake spawning... -
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... -
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... -
Validation of the periodicity of growth increment deposition in otoliths from the larval and early juvenile stages of two cyprinids from the Orange–Vaal river system, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: BR Paxton --- Water Research Group (Ecology), School of Environmental Sciences and Development, Potchefstroom Campus, South Africa GC O'Brien --- Water Research Group (Ecology), School of Environmental Sciences and Development, Potchefstroom Campus, South Africa JA Slingsby --- South African Environmental Observatory Network, South Africa R Copin --- Zoology Department, South AfricaThis study tested the hypothesis that growth increments in larval largemouth yellowfish Labeobarbus kimberleyensis and smallmouth yellowfish L. aeneus from the Orange–Vaal river system, South Africa, are deposited daily. The periodicity of increment formation was determined by regular sampling and... -
Adult Movement and Larval Dispersal of Argyrozona Argyrozona (Pisces: Sparidae) from a Temperate Marine Protected Area
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S. L. Brouwer M. H. Griffiths M. J. RobertsAdult emigration and larval dispersal of carpenter Argyrozona argyrozona from the Tsitsikamma National Park (TNP), South Africa, were investigated using mark-recapture data and Acoustic Doppler Current Profiler measurements of currents. Tagging data showed that adult carpenter were mainly resident, with... -
Currents along the Tsitsikamma coast, South Africa, and potential transport of squid paralarvae and ichthyoplankton
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts M van den BergIn July 1998, a bottom-mounted Acoustic Doppler Current Profiler was deployed at 36m depth in the centre of the Tsitsikamma National Park on the eastern Agulhas Bank, South Africa. The purpose was to investigate transport of chokka squid Loligo vulgaris... -
Influence of oceanographic fronts and low oxygen on the distribution of ichthyoplankton in the Benguela and southern Angola currents
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: W Ekau HM VerheyeThe study focuses on ichthyoplankton populations in the southern Angola Current, the Angola-Benguela Front and the coastal upwelling area of the northern and central Benguela Current. The horizontal and vertical distributions of eggs and larvae of sardine Sardinops sagax, anchovy... -
First Lagrangian ROMS–IBM simulations indicate large losses of chokka squid Loligo reynaudii paralarvae from South Africa's Agulhas Bank
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Department of Environmental Affairs, South Africa C Mullon --- , FrancePresent knowledge of ocean currents based on in situ observation and models suggests that passive biological material such as eggs and larvae can be advected offshore away from the Agulhas Bank, South Africa, and hence removed from the ecosystem on... -
Vertical distribution of small pelagic fish eggs and larvae on the eastern Agulhas Bank, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: W Osman --- Department of Zoology and Marine Research Institute, South Africa CL Moloney --- Department of Zoology and Marine Research Institute, South Africa CD van der Lingen --- Department of Agriculture, South AfricaVertical distributions of anchovy Engraulis encrasicolus and sardine Sardinops sagax eggs and larvae within the upper 50 m of the water column on the eastern Agulhas Bank, South Africa, were examined using discrete depth samples collected with a multiple, opening/closing... -
Cyclonic eddies reveal Oegopsida squid egg balloon masses in the Agulhas Current, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Oceans and Coasts, Department of Environmental Affairs, South Africa T Zemlak --- Department of Integrative Biology, Canada A Connell --- , South AfricaIn 2005, 2006, 2007 and 2011, distinct Oegopsida squid egg masses were observed by scuba divers on the narrow southern KwaZulu-Natal (KZN) shelf in depths of 35–50 m off the coastal resorts of Park Rynie, Pumula and Port Edward, South... -
Diet and prey selection in late-stage larvae of five species of fish in a temperate estuarine nursery
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: NA Strydom --- Department of Zoology, South Africa K Sutherland --- Department of Zoology, South Africa TH Wooldridge --- Department of Zoology, South AfricaThe plankton assemblage of the permanently open Sundays Estuary in South Africa was sampled seasonally to provide further information on the feeding ecology of the larval stages of fishes in temperate estuaries. Collections were made between winter 2007 and autumn... -
Diel vertical migration of anchovy Engraulis encrasicolus larvae in the northern Benguela
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: EK Stenevik S Sundby R CloeteThe diel vertical migration of anchovy Engraulis encrasicolus larvae was studied in the northern Benguela during a survey in April 2001. The diel pattern is described in relation to the degree of swimbladder inflation and the vertical structure of temperature... -
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... -
Preliminary examination of hatching season and growth of Engraulicypris sardella (Pisces: Cyprinidae) larvae and juveniles in Lake Malawi
Item type: Journal Article • Journal: African Zoology • Authors: Shinsuke Morioka --- Department of Aquaculture and Fisheries Science, Bunda College of Agriculture, Malawi Emmanuel Kaunda --- Department of Aquaculture and Fisheries Science, Bunda College of Agriculture, MalawiThe hatching period and the growth of Malawian cyprinid Engraulicypris sardella larvae and juveniles collected from two sites along the southwestern shoreline of Lake Malawi were investigated using otolith increment information. The lapillus was used to determine the age in... -
Pycnoclavella (Tunicata: Ascidiacea) species from the West Indian Ocean
Item type: Journal Article • Journal: African Zoology • Authors: Patricia Kott --- Queensland Museum, AustraliaThree new Pycnoclavella species, recorded from a number of locations in Algoa and Plettenberg bays, suggest an unusual diversity for this genus in South African waters and indicate the extent to which the fauna of this part of the world... -
Cercariae shed by Bulinus tropicus (Krauss, 1848) in the Free State, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: P.H. King --- Department of Biology, South Africa J.G. van As --- Department of Zoology and Entomology, South AfricaThe present study forms part of a survey of the snail-borne trematode parasites in the Free State Province, South Africa. The planorbid mollusc Bulinus tropicus (Krauss, 1848) is the most abundant and widespread freshwater snail in this area. Parasitological studies... -
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... -
Biophysical models of larval dispersal in the Benguela Current ecosystem
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Lett --- UMI IRD 209 UPMC UMMISCO, Centre de Recherche Halieutique Méditerranéenne et Tropicale, France CD van der Lingen --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries, South Africa BR Loveday --- Remote Sensing Group, Plymouth Marine Laboratory, UK CL Moloney --- Marine Research Institute and Department of Biological Sciences, South AfricaWe synthesise and update results from the suite of biophysical, larval-dispersal models developed in the Benguela Current ecosystem. Biophysical models of larval dispersal use outputs of physical hydrodynamic models as inputs to individual-based models in which biological processes acting during... -
Life cycle of chokka-squid Loligo reynaudii in South African waters
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MR Lipiński --- Department of Ichthyology and Fisheries Science, South Africa JSF van der Vyver --- Department of Ichthyology and Fisheries Science, South Africa P Shaw --- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University Penglais, UK WHH Sauer --- Department of Ichthyology and Fisheries Science, South AfricaThis short note summarises past and current knowledge of the life cycle of chokka-squid Loligo reynaudii d’Orbigny, 1845, in South African waters. Prior to approximately 2010, the chokka-squid stock was considered simple and uniform, with one paralarval pool, the drift... -
The ‘suitcase hypothesis’: Can entrainment of meroplankton by eddies provide a pathway for gene flow between Madagascar and KwaZulu-Natal, South Africa?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Ockhuis --- Cape Peninsula University of Technology, South Africa JA Huggett --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa G Gouws --- African Coelacanth Ecosystem Programme (ACEP), South Africa C Sparks --- Cape Peninsula University of Technology, South AfricaSimilarities in the marine fauna found off the coasts of southern Madagascar and KwaZulu-Natal Province (KZN), South Africa, led to the development of the ‘suitcase project,’ with the aim of establishing whether eddies that form off southern Madagascar may package... -
Metabolic activity throughout early development of dusky kob Argyrosomus japonicus (Sciaenidae)
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Edworthy --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa NC James --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa B Erasmus --- Department of Ichthyology and Fisheries Science, South Africa JOG Kemp --- Department of Ichthyology and Fisheries Science, South Africa H Kaiser --- Department of Ichthyology and Fisheries Science, South Africa WM Potts --- Department of Ichthyology and Fisheries Science, South AfricaThe physiology of fishes in the early stages of development remains poorly assessed despite the importance of identifying energy bottlenecks in organisms faced with changing environmental conditions. This study describes the metabolic activity of dusky kob Argyrosomus japonicus throughout its... -
The bionomics of whitegrub species (Coleoptera: Scarabaeidae) affecting commercial forestry re-establishment in representative areas of the South African summer-rainfall region
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Derian Echeverri-Molina --- Department of Biology, School of Science and Technology, Sefako Makgatho Health Sciences University, South Africa Prem Govender --- Research and Postgraduate Studies Directorate, Sefako Makgatho Health Sciences University, South AfricaSouth African commercial forestry plants mainly Eucalyptus, Pinus and Acacia species. Invertebrate pests play a significant role in the establishment phase of these exotic trees. Whitegrubs, in particular, are known to affect seedling survival during this period. Their pest status... -
Review of fish life history strategies associated with warm temperate South African estuaries and a call for effective integrated management
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NA Strydom --- Department of Zoology, South Africa Y Kisten --- Department of Zoology, South AfricaRefuge and feeding areas for young fish in estuaries are important for the survival of fish and replenishment of coastal fish stocks, particularly in the temperate south east coast of southern Africa. Larvae and juveniles of important fishery species recruit... -
Is the largest African penguin colony in South Africa influencing local ocean productivity?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: G Passuni --- , South Africa LRD Human --- , South Africa SN Riddick --- , United States P Pattrick --- , South Africa M Bizani --- , South Africa SHP Deyzel --- , South Africa NA Strydom --- , South Africa TG Bornman --- , South Africa L Pichegru --- , South AfricaIn coastal waters, nutrient supplies originate principally from allochthonous sources, such as inputs from rivers, estuaries or oceanic waters. Recently, it has been suggested that marine life contributes to the nutrient load, with penguin colonies being the largest contributor worldwide... -
Endohelminth parasites of male and female tigerfish, Hydrocynus vittatus (Castelnau, 1861), from the Sanyati basin in Lake Kariba
Item type: Journal Article • Journal: African Zoology • Authors: Nyasha Mabika --- University of Johannesburg, South Africa Maxwell Barson --- University of Botswana, Botswana Cobus Van Dyk --- University of Johannesburg, South Africa Annemariè Avenant-Oldewage --- University of Johannesburg, South AfricaTigerfish (Hydrocynus vittatus Castelnau, 1861) is of considerable importance in both the commercial and recreational fishery activities of Lake Kariba. In our previous paper (Mabika et al. 2019) we provided information on the seasonal occurrence of metazoan parasites of H... -
Description of the tadpoles of two Cameroonian frogs, Leptodactylodon axillaris and L. perreti (Anura: Arthroleptidae)
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Deise Cruz --- California Academy of Sciences, USA AnneliseL. Dawson --- Harvard University, USA DavidC. Blackburn --- California Academy of Sciences, USAWe describe the tadpoles of two closely related frog species of the genus Leptodactylodon (family Arthroleptidae), L. axillaris and L. perreti, that are restricted to the mountains of Cameroon. Tadpoles were collected from near the type locality of each species... -
Contrast in larval sensitivity to low pH in sea urchins from neighbouring seagrass meadows at Inhaca Island, Mozambique
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JA Duvane --- Eduardo Mondlane University, Mozambique D Cossa --- Eduardo Mondlane University, Mozambique DC de Abreu --- Eduardo Mondlane University, Mozambique M Mafambissa --- Eduardo Mondlane University, Mozambique MP Scarlet --- Eduardo Mondlane University, Mozambique A Macia --- Eduardo Mondlane University, Mozambique S Dupont --- University of Gothenburg, SwedenOcean acidification presents a major threat to marine life, and a large body of evidence has documented its negative effects on various marine species and ecosystems. Recent meta-analyses highlight the key role of local adaptation and have linked species’ sensitivity...