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Genetic and morphological variation of the lanternfish Lampanyctodes hectoris (Myctophiformes: Myctophidae) off southern Africa
Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: W. K. Florence P. A. Hulley B. A. Stewart M. J. GibbonsGenetic and morphological variation within the southern African population of Lampanyctodes hectoris was analysed. A total of 15 enzymes, encoding 22 isozyme loci, was examined (n = 327); seven were polymorphic. The percentage of polymorphic loci ranged from 13.6 to... -
Living on the bare edge: fitness consequences for Cape Gannets Morus capensis at Bird Island, Algoa Bay
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: David Green --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology, South Africa Pierre Pistorius --- DST/NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology, South AfricaAvian breeding colonies often suffer high levels of predation along their margins. Nest predation is a major fitness concern for parents and therefore nests inside of the colony edge might be at a premium. This was tested through studying the... -
Oceanic variability in the western sector of Algoa Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: EH Schumann JRS Churchill HJ ZaaymanThe city of Port Elizabeth lies in the western sector of Algoa Bay, and a number of projects have investigated the oceanic temperature, salinity and current structures in the vicinity. This paper analyses past results, and then incorporates measurements of... -
Epipelagic siphonophores off the east coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: D Thibault-Botha MJ GibbonsThis work represents the first systematic analysis of the common Siphonophora from the Agulhas Current (South-West Indian Ocean). A total of 56 species of siphonophores was collected from a series of three largely epipelagic cruises between Algoa Bay and the... -
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... -
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... -
Coastal oceanic climate change and variability from 1982 to 2009 around South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Rouault --- Department of Oceanography, Marine Research Institute, South Africa B Pohl --- Centre de Recherches de Climatologie, France P Penven --- , FranceChanges and fluctuations in sea surface temperature (SST) around the South African coast are analysed at a monthly scale from 1982 to 2009. There is a statistically significant negative trend of up to 0.5 °C per decade in the southern... -
Shelf currents, lee-trapped and transient eddies on the inshore boundary of the Agulhas Current, South Africa: their relevance to the KwaZulu-Natal sardine run
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Oceans and Coasts, Department of Environmental Affairs, South Africa CD van der Lingen --- Branch Fisheries, Department of Agriculture, South Africa C Whittle --- Department of Oceanography, South Africa M van den Berg --- Oceans and Coasts, Department of Environmental Affairs, South AfricaThe existence and strength of the annual KwaZulu-Natal (KZN) sardine run has long been a conundrum to fishers and scientists alike ― particularly that the sardine Sardinops sagax migrate along the narrow Transkei shelf against the powerful, warm Agulhas Current... -
Movement patterns of coastal bottlenose dolphins in the presence of a fast-flowing, prevailing current: shore-based observations at Cape Vidal, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Photopoulou --- Sea Mammal Research Unit, UK PB Best --- , South Africa PS Hammond --- Sea Mammal Research Unit, UK KP Findlay --- Department of Oceanography, University of Cape Town, South AfricaThe presence and movement of Indo-Pacific bottlenose dolphins Tursiops aduncus were investigated using shore-based observations made during a humpback whale Megaptera novaeangliae migration survey at Cape Vidal, South Africa, undertaken between June and October 1988–1991. Occurrence was analysed as counts... -
Abrupt environmental shift associated with changes in the distribution of Cape anchovy Engraulis encrasicolus spawners in the southern Benguela
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Roy CD van der Lingen JC Coetzee JRE LutjeharmsCape anchovy Engraulis encrasicolus spawners in the southern Benguela showed an eastward shift in their distribution on the Agulhas Bank that occurred abruptly in 1996 and has since persisted. We assessed whether this shift was environmentally mediated by examining sea... -
Comparative ecology of the copepods Calanoides carinatus and Calanus agulhensis — the influence of temperature and food
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JA Huggett AJ Richardson JG FieldHypotheses regarding temperature, food abundance and food size were tested to explore niche separation between Calanoides carinatus, an abundant copepod in the cool and food-rich southern Benguela upwelling system, and Calanus agulhensis, the dominant copepod on the warmer, relatively food-poor... -
Trophic investigations of Cape fur seals at the easternmost extreme of their distribution
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Connan --- Department of Zoology, South Africa GJG Hofmeyr --- Department of Zoology, South Africa MJ Smale --- Department of Zoology, South Africa PA Pistorius --- Department of Zoology, South AfricaThe diet of Cape fur seals Arctocephalus pusillus pusillus in the eastern portion of their distribution has received little attention previously, and was studied using traditional methods only. In 2013 we therefore assessed the diet of seals at the easternmost... -
Spatial and seasonal patterns in sighting rate and life-history composition of the white shark Carcharodon carcharias at Mossel Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Ryklief --- Department of Zoology, South Africa PA Pistorius --- Department of Zoology, South Africa R Johnson --- Oceans Research, South AfricaWhite sharks Carcharodon carcharias aggregate at specific times of the year at localities along the South African coast. At Mossel Bay, on the southern Cape coast, four sites were sampled (Seal Island, Hartenbos, Kleinbrak and Grootbrak) to investigate spatial and... -
A comparison of genetic structure in two low-dispersal crabs from the Wild Coast, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: Y Qhaji --- Molecular Zoology Laboratory (Aquatic Division), Department of Zoology, South Africa B Jansen van Vuuren --- Molecular Zoology Laboratory (Aquatic Division), Department of Zoology, South Africa I Papadopoulos --- Molecular Zoology Laboratory (Aquatic Division), Department of Zoology, South Africa CD McQuaid --- Department of Zoology and Entomology, South Africa PR Teske --- Molecular Zoology Laboratory (Aquatic Division), Department of Zoology, South AfricaThe Wild Coast in south-eastern South Africa is strongly influenced by the warm, southward-flowing Agulhas Current. This current has a significant impact on dispersal in the coastal biota of the region, and facilitates high levels of connectivity among populations. However,... -
Distribution of calcareous nannoplankton in surface sediments along the northern KwaZulu-Natal Bight, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MN Ovechkina --- Geological Sciences, School of Agricultural, Earth and Environmental Sciences, South Africa MB Mostovski --- School of Life Sciences, South Africa R Uken --- Geological Sciences, School of Agricultural, Earth and Environmental Sciences, South AfricaThe coccolith assemblages from seafloor sediments over the inner shelf in the northern region of the KwaZulu- Natal Bight on the east coast of South Africa were identified and their distribution determined. In all, 29 Recent species and taxonomic groups,... -
Species composition, abundance and biomass of microphytoplankton in the KwaZulu-Natal Bight on the east coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JS van der Molen --- Council for Scientific and Industrial Research, South Africa UM Scharler --- School of Life Sciences, South Africa D Muir --- Medgar Evers College, City University of New York, USANearshore marine environments are influenced by an array of variables that can either be land-derived or of marine origin, and nearshore phytoplankton communities may differ in their taxonomic composition and biomass in response to such variables. The KwaZulu-Natal Bight (hereafter... -
Riverine influence determines nearshore heterogeneity of nutrient (C, N, P) content and stoichiometry in the KwaZulu-Natal Bight, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: UM Scharler --- School of Life Sciences, South Africa MJ Ayers --- School of Life Sciences, South Africa AM de Lecea --- School of Life Sciences, South Africa M Pretorius --- Department of Biodiversity and Conservation Biology, South Africa ST Fennessy --- Oceanographic Research Institute, South Africa JA Huggett --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa CF MacKay --- Oceanographic Research Institute, South Africa D Muir --- Medgar Evers College, USARiverine influences on nearshore oceanic habitats often have detrimental consequences leading to algal blooms and hypoxia. In oligo- to mesotrophic systems, however, nutrient delivery via rivers may stimulate production and even be a vital source of nutrients, as may nutrient... -
A system-level modelling perspective of the KwaZulu-Natal Bight ecosystem, eastern South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: UM Scharler --- School of Life Sciences, South Africa RC van Ballegooyen --- Coastal Systems Research Group, South Africa MJ Ayers --- School of Life Sciences, South AfricaThe KwaZulu-Natal Bight comprises the only sizeable shelf region on the eastern coast of South Africa, and is influenced by both the Agulhas Current on its seaward side and rivers and estuaries on its landward side. Established knowledge of the... -
Dynamics and role of the Durban cyclonic eddy in the KwaZulu-Natal Bight ecosystem
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LA Guastella --- Bayworld Centre for Research and Education, South Africa MJ Roberts --- Ocean Sciences and Marine Food Security, South AfricaThe semi-permanent Durban Eddy is a mesoscale, lee-trapped, cold-core cyclonic circulation that occurs off the east coast of South Africa between Durban in the north and Sezela, some 70 km to the south. When present, strong north-eastward countercurrents reaching 100... -
Circulation of shelf waters in the KwaZulu-Natal Bight, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Ocean Sciences and Marine Food Security, South Africa C Nieuwenhuys --- Bayworld Centre for Research and Education, South Africa LA Guastella --- Bayworld Centre for Research and Education, South AfricaShip-based acoustic Doppler current profiler (S-ADCP) technology, used in survey mode, has enabled near- synoptic views of the in situ 3-D current field in the KwaZulu-Natal (KZN) Bight to be elucidated for the first time. Data acquired by the research... -
Observations and mechanisms of upwelling in the northern KwaZulu-Natal Bight, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MJ Roberts --- Ocean Sciences and Marine Food Security, South Africa C Nieuwenhuys --- Bayworld Centre for Research and Education, South AfricaNew in situ time-series data were acquired by two ADCP moorings placed on the shelf off Richards Bay on the east coast of South Africa at depths of 25 m and 582 m between October 2009 and August 2010. The... -
Analysis of bycatch in the South African midwater trawl fishery for horse mackerel Trachurus capensis based on observer data
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JR Reed --- Marine Research Institute, Department of Biological Sciences, South Africa SE Kerwath --- Marine Research Institute, Department of Biological Sciences, South Africa CG Attwood --- Marine Research Institute, Department of Biological Sciences, South AfricaThe South African midwater trawl fishery targets adult horse mackerel Trachurus capensis. The bulk of the catch is taken by a single freezer-trawler, the biggest fishing vessel operating in South African waters. As fishing takes place off the south coast... -
Life history, distribution and seasonal movements of a threatened South African endemic seabream, Chrysoblephus gibbiceps
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CG Attwood --- Department of Biological Sciences and the Marine Research Institute, South Africa ME Dawson --- Department of Biological Sciences and the Marine Research Institute, South Africa SE Kerwath --- Department of Biological Sciences and the Marine Research Institute, South Africa C Wilke --- Branch: Fisheries Management, Department of Agriculture, Forestry and Fisheries (DAFF), South AfricaThe red stumpnose Chrysoblephus gibbiceps (Sparidae) is a South African endemic seabream that has been severely depleted by fishing. A total of 678 C. gibbiceps were sampled by line and trawl fishing for a study of their morphology, age, growth,... -
Zoogeography of marine Bryozoa around South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MK Boonzaaier-Davids --- , South Africa WK Florence --- , South Africa MJ Gibbons --- , South AfricaThe zoogeography of marine Bryozoa around South Africa was investigated using published distribution records, museum catalogues, and an examination of previously unworked bryozoan material in (mostly) museum collections. Although a total of 276 valid species are recognised, it was not... -
Distribution patterns of intertidal oribatid mites (Acari, Oribatida) from South African shores and their relationship to temperature
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Pfingstl --- , Austria J Baumann --- , Austria J-A Neethling --- , South Africa I Bardel-Kahr --- , Austria EA Hugo-Coetzee --- , South AfricaA faunistic study of the intertidal oribatid mite fauna of South Africa’s coastline revealed the presence of four species from three families, showing specific biogeographic patterns. Their occurrences show a clear east–west divide, with a small gap near East London... -
Ectoparasites infecting the heads and gills of commercially valuable marine fishes in South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Mark Weston --- , South Africa Irfan Nunkoo --- , South Africa Cecile Reed --- , South Africa Carl D van der Lingen --- , South AfricaThe South African marine environment is highly diverse, containing >12 000 species of flora and fauna. However, the state of knowledge of marine fish parasites in South African waters is still relatively poor. This study used opportunistic sampling to examine... -
Long-term interannual temperature variability across the KwaZulu-Natal Bight as a technique for monitoring the complex uThukela Marine Protected Area, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N Ramsarup --- University of Cape Town, South Africa T Morris --- , South Africa J Hermes --- University of Cape Town, South Africa M Dicken --- Institution for Coastal and Marine Research, Ocean Sciences Campus, Nelson Mandela University, South AfricaThe uThukela Marine Protected Area (MPA), situated on the continental shelf of the KwaZulu-Natal (KZN) Bight on the northeastern coast of South Africa, has been identified as a vital ecological region. Knowledge of the oceanographic dynamics in the region is... -
Spatial and temporal distribution of shallow-water hake Merluccius capensis off the south coast of South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LCJ Nomxego --- Fisheries and the Environment (DFFE), South Africa OS Kjesbu --- Institute of Marine Research, Norway WHH Sauer --- Rhodes University, South Africa MR Lipinski --- Rhodes University, South AfricaThis study investigated the spatial and temporal distribution of shallow-water hake Merluccius capensis off the south coast of South Africa, using 1 807 females collected by bottom trawling during industry and research surveys between 2014 and 2016. Mean body size... -
Comparison of light trap designs for assessments of positively phototactic invertebrate and larval assemblages in urbanised coastal systems
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: NP Mpanza --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa P Pattrick --- South African Environmental Observation Network (SAEON), Elwandle Coastal Node, South Africa F Porri --- South African Institute for Aquatic Biodiversity (SAIAB), South AfricaThe construction of seawalls is increasing the extent of artificial infrastructure along coastlines globally. Such development compromises substrate complexity of the natural environment which is crucial for major life functions of larvae (invertebrates and fish). Understanding the physical and biological...