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A comparison of condition factor and gonadosomatic index of sardine Sardinops sagax stocks in the northern and southern Benguela upwelling ecosystems, 1984–1999

Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: A. Kreiner C. D. van der Lingen P. Fréon

Time-series of condition factor (CF) and gonadosomatic index (GSI) were generated using general linear models (GLM) for sardine Sardinops sagax stocks in the northern and southern Benguela ecosystems over the period 1984–1999. During this period the biomass of sardine in...

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Influence of buoyancy and vertical distribution of sardine Sardinops sagax eggs and larvae on their transport in the northern Benguela ecosystem

Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: E. K. Stenevik S. Sundby R. Cloete

In recent years, sardine Sardinops sagax spawning has been recorded inshore off central Namibia. Field observations on eggs and laboratory measurements show that spawning, demonstrated by the distribution of newly spawned eggs, takes place just below the upper mixed layer...

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Changes in abundance of the northern Benguela sardine stock during the decade 1990–2000, with comments on the relative importance of fishing and the environment

Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: D. C. Boyer H. J. Boyer I. Fossen A. Kreiner

The northern Benguela stock of sardine Sardinops sagax used to be considered one of the major clupeoid stocks of the world; it supported an average annual catch of >700 000 tons throughout the 1960s. The stock has been in a...

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Identification and classification of vertical chlorophyll patterns in the Benguela upwelling system and Angola-Benguela front using an artificial neural network

Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: N. F. Silulwane A. J. Richardson F. A. Shillington B. A. Mitchell-Innes

Information on the vertical chlorophyll structure in the ocean is important for estimating integrated chlorophyll a and primary production from satellite. For this study, vertical chlorophyll profiles from the Benguela upwelling system and the Angola-Benguela front were collected in winter...

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Changes in some key biological parameters of the northern Benguela sardine stock

Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: I. Fossen D. C. Boyer H. Plarre

During the past 50 years, more than 15 million tons of sardine have been harvested from the northern Benguela ecosystem. The sardine population has undergone changes in abundance estimated to range over more than two orders of magnitude, but for...

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An overview of the living marine resources of Namibia

Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: D. C. Boyer I. Hampton

This paper gives an overview of the main living marine resources of Namibia. It focuses on the scientific research conducted during the past decade as input to the management of these resources. The distribution and habitats of the most important...

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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. Gibbons

Genetic 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...

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Diet of sardine Sardinops sagax in the southern Benguela upwelling ecosystem

Item type: Journal Article • Journal: South African Journal of Marine Science • Authors: C. D. Van Der Lingen

The diet of sardine Sardinops sagax in the southern Benguela was investigated by microscopic examination of stomach contents. The relative dietary importance of prey size and prey type was assessed by calculating the carbon content of prey items. Sardine is...

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Drift Patterns of Anchovy Engraulis Capensis Larvae in The Southern Benguela, and Their Possible Importance for Recruitment

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M. D. Skogen L. J. Shannon J. E. Stiansen

In the southern Benguela, successful recruitment of Cape anchovy Engraulis capensis is highly variable and seems to be dependent on the spawning biomass only to a small extent. This paper investigates how the variations in the drift patterns of larvae...

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Observations on the Diel Vertical Distribution of Hydromedusae in the Southern Benguela

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: E. Buecher M. J. Gibbons

Diel vertical migration (DVM) of six common species of hydromedusae was investigated during two drogue studies conducted in St Helena Bay on the west coast of South Africa in February 1995. Clytia spp., Obelia spp. and Bougainvillia macloviana, were largely...

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In Situ Measurements of the Acoustic Target Strength of Cape Horse Mackerel Trachurus Trachurus Capensis Off Namibia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: B. E. Axelsen G. Bauleth-D'Almeida A. Kanandjembo

The acoustic target strength (TS) of Cape horse mackerel Trachurus trachurus capensis was measured in situ at 38 kHz during two surveys over the Namibian continental shelf in 1998 and 1999 using a SIMRAD EK500 echosounder/ES38D submersible split-beam transducer. Scattered...

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Hydromedusae Off the Orange River Mouth, Southern Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C. Sparks M. J. Gibbons

A total of 242 zooplankton samples from the upper 100 m of the water column was collected discontinuously from March 1997 to January 1999 off the Orange River mouth on the west coast of southern Africa. Six species of hydromedusae...

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Ecosystem approach to fisheries management in the southern Benguela: a workshop overview

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. J. Shannon K. L. Cochrane C. L. Moloney P. Fréon

A workshop was held in Cape Town in December 2002 to introduce the concept of an ecosystem approach to fisheries (EAF) management in the southern Benguela, and to examine the options for implementing an EAF in South Africa. The workshop...

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An ecosystem approach to fisheries in the southern Benguela context

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K. L. Cochrane C. J. Augustyn A. C. Cockcroft J. H. M. David M. H. Griffiths J. C. Groeneveld M. R. Lipińnski M. J. Smale C. D. Smith R. J. Q. Tarr

The 2001 Reykjavík Declaration on Responsible Fisheries in the Marine Ecosystem and the Plan of Implementation of the 2002 World Summit on Sustainable Development highlighted the need in fisheries to look beyond considering only the target species and to consider...

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Contributions of the Benguela ecology programme to pelagic fisheries management in South Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C. L. Moloney C. D. Van Der Lingen L. Hutchings J. G. Field

In 1982, the Benguela Ecology Programme (BEP) created a formal, multi-institutional research partnership in South Africa. During the next two decades, the BEP directed many aspects of pelagic ecosystem research in the southern Benguela upwelling region, aiming to improve fisheries...

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An ecosystem framework for fisheries management in the southern Benguela upwelling system

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. J. Shannon C. L. Moloney

A "four-step framework" for applying ecosystem approaches to fisheries management in the southern Benguela is proposed. First, static ecosystem models can be used to highlight important interactions by assessing the net trophic impacts of each species on all the others...

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Ecosystem approach to fisheries management in the northern Benguela: the Namibian experience

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J-P. Roux L. J. Shannon

The northern Benguela marine resources have a long history of questionable management primarily because of the limitations of management measures under the political framework of the time (either free access or under an international authority with no national representation, authority...

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Quantification and representation of potential spatial interactions in the southern Benguela ecosystem

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. Drapeau L. Pecquerie P. Fréon L. J. Shannon

This work explores the potential spatial interactions between 13 key commercial species of the southern Benguela ecosystem: sardine Sardinops sagax, anchovy Engraulis encrasicolus, round herring Etrumeus whiteheadi, horse mackerel Trachurus trachurus capensis, chub mackerel Scomber japonicus, chokka squid Loligo vulgaris...

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Modelling stock dynamics in the southern Benguela ecosystem for the period 1978–2002

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L. J. Shannon V. Christensen C. J. Walters

An ecosystem model of the southern Benguela was fitted to available time-series data for the period 1978–2002, to explore how changes in target fish populations in this ecosystem can be attributed to feeding interaction terms and population control patterns, the...

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Seasonal and spatial variability of dominant copepods along a transect off Walvis Bay (23°S), Namibia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: FC Hansen RR Cloete HM Verheye

The study provides the first quantitative analysis of changes in zooplankton abundance and community structure in the Walvis Bay area, off Namibia, over a full seasonal cycle (February–December 2000). Zooplankton was collected monthly along a 90-nautical-mile transect. Calanoid copepods were...

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Distribution of nutrients, chlorophyll and phytoplankton primary production in relation to hydrographic structures bordering the Benguela-Angolan frontal region

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N Wasmund H-U Lass G Nausch

The aim of this study was to determine the characteristic rates of phytoplankton production in water bodies bordering the Benguela-Angolan frontal region and differing in their hydrographic, hydrochemical and biological properties. Two cruises were undertaken in the vicinity of the...

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Preliminary documentation and assessment of fish diversity in sub-Saharan African estuaries

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK Whitfield

Lists of indigenous fish species sampled in cool-temperate, warm-temperate, subtropical and tropical estuaries in sub-Saharan Africa were compiled from both published and unpublished data. Comparisons were conducted at the species and family level between the fish assemblages recorded in the...

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Vertical migration, catchability and acoustic assessment of semi-pelagic Cape horse mackerel Trachurus trachurus capensis in the southern Benguela

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Barange SC Pillar I Huse L Hutchings

The vertical distribution and migration of the Cape horse mackerel Trachurus trachurus capensis were investigated on the basis of midwater and bottom trawl collections taken over diel cycles at two sites on South Africa's south coast. Attempts were also made...

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Characterising and comparing the spawning habitats of anchovy Engraulis encrasicolus and sardine Sardinops sagax in the southern Benguela upwelling ecosystem

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: NM Twatwa CD van der Lingen L Drapeau CL Moloney JG Field

The spawning habitats of anchovy Engraulis encrasicolus and sardine Sardinops sagax in the southern Benguela upwelling ecosystem were characterised by comparing their egg abundances with environmental variables measured concomitantly during two different survey programmes: the South African Sardine and Anchovy...

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Water-body preferences of dominant calanoid copepod species in the Angola-Benguela frontal zone

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N Loick W Ekau HM Verheye

The distribution of five dominant calanoid copepods was related to different water masses in the Angola-Benguela Front system. Five water bodies were identified by principal component analysis, on the basis of abiotic parameter such as temperature, salinity, dissolved oxygen, phosphate,...

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Maintenance mechanisms of plankton populations in frontal zones in the Benguela and Angola Current systems: a preface

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HM Verheye W Ekau

This preface provides the background to, and synthesis of research findings from, a set of environmental research-driven cruises off southern Angola, Namibia and South Africa during February–March 2002, under the auspices the BENguela Environment Fisheries Interaction and Training (BENEFIT) Programme...

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A demonstration of the hydrographic partition of the Benguela upwelling ecosystem at 26°40'S

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CM Duncombe Rae

Continuous CTD data from a series of recent cruises show that the distribution of the water mass characteristics in the central Benguela region from the Orange River mouth (28°38'S) to alvis Bay (22°57'S) is discontinuous in the central and intermediate...

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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 Verheye

The 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...

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Life strategies, energetics and growth characteristics of Calanoides carinatus (Copepoda) in the Angola-Benguela frontal region

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: HM Verheye W Hagen H Auel W Ekau N Loick I Rheenen P Wencke S Jones

Rates of daily egg production, moulting and egg hatching success, as well as total lipid content and composition of Calanoides carinatus, were measured in the region of the southern Angola Curre nt SAC), the Angola-Benguela Front (ABF) and the coastal...

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Tropical South-East Atlantic response to ENSO as an ecosystem indicator for the southern Benguela

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: MR Jury

The response of the tropical South-East Atlantic Ocean to the El Niño Southern Oscillation (ENSO) was studied for the period 1950–1999. Interaction between the ocean thermocline 'see-saw' and the overlying zonal wind circulation was examined. The two are closely linked...

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How can science contribute to an ecosystem approach to pelagic, demersal and rock lobster fisheries in South Africa?

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LJ Shannon PM Cury D Nel CD Van Der Lingen RW Leslie SL Brouwer AC Cockcroft L Hutchings

South Africa is committed to moving towards an Ecosystem Approach to Fisheries (EAF) and has laid the foundations for this using a three-pronged approach: through a project (EAF Feasibility Study) under the Benguela Current Large Marine Ecosystem Programme; through a...

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Real-time monitoring of harmful algal blooms in the southern Benguela

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Fawcett S Bernard GC Pitcher TA Probyn A du Randt

The southern Benguela Current region off South Africa is subject to frequent harmful algal blooms (HABs), which can have serious impacts — both through the introduction of toxins into the ecosystem and the collapse of high-biomass blooms leading to anoxia...

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Cysts of Alexandrium catenella on the west coast of South Africa: distribution and characteristics of germination

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LB Joyce GC Pitcher

Cysts of the toxic dinoflagellate Alexandrium catenella (Whedon and Kofoid) Balech were found in the sediments of the southern Namaqua shelf, on the west coast of South Africa, with a maximum recorded abundance of 238 cysts ml−1 wet sediment. Experimental...

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Comparative trophodynamics of anchovy Engraulis encrasicolus and sardine Sardinops sagax in the southern Benguela: are species alternations between small pelagic fish trophodynamically mediated?

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CD van der Lingen L Hutchings JG Field

The results of detailed morphological, experimental, field and modelling studies on various aspects of the trophic ecology of sardine Sardinops sagax and anchovy Engraulis encrasicolus in the Benguela ecosystem are synthesised, and differences in the trophodynamics of these two species...

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Remotely sensed variability of temperature and chlorophyll in the southern Benguela: upwelling frequency and phytoplankton response

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SJ Weeks R Barlow C Roy FA Shillington

High-resolution (1km) satellite data from the NOAA AVHRR (Advanced Very High Resolution Radiometer) and OrbView-2 SeaWiFS (Sea-viewing Wide Field-of-view Sensor) are used to investigate the upper layer dynamics of the southern Benguela ecosystem in more detailed space and time scales...

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Comparison of assemblages and some life-history traits of seabirds in the Humboldt and Benguela systems

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RJM Crawford E Goya J-P Roux CB Zavalaga

There are 21 and 15 species of seabirds that breed in the Humboldt and Benguela upwelling systems respectively. Only two species of gull are common to both systems, one as an endemic subspecies to the Benguela system. Eleven species and...

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Density-dependent changes in reproductive parameters and condition of southern Benguela sardine Sardinops sagax

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CD van der Lingen P Fréon TP Fairweather JJ van der Westhuizen

The sardine Sardinops sagax population in the southern Benguela has undergone substantial fluctuations in size over the past 50 years, collapsing from an apparently large population in the 1950s to low levels in the mid-1960s, remaining low for the next...

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Migration redefined? Seasonality, movements and group composition of humpback whales Megaptera novaeangliae off the west coast of South Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: J Barendse --- , South Africa PB Best --- , South Africa M Thornton --- , South Africa C Pomilla --- , USA I Carvalho --- , USA HC Rosenbaum --- , USA

The migration of Southern Hemisphere humpback whales Megaptera novaeangliae between their feeding and breeding areas has thus far been considered a highly predictable and seasonal event. However, previous observations on the humpbacks that pass through the nearshore waters of the...

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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 --- , France

Changes 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...

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Surviving off junk: low-energy prey dominates the diet of African penguins Spheniscus demersus at Mercury Island, Namibia, between 1996 and 2009

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Ludynia --- Animal Demography Unit, Department of Zoology, South Africa J-P Roux --- Animal Demography Unit, Department of Zoology, South Africa R Jones --- Ministry of Fisheries and Marine Resources, Namibia J Kemper --- Ministry of Fisheries and Marine Resources, Namibia LG Underhill --- Animal Demography Unit, Department of Zoology, South Africa

The diet of African penguins Spheniscus demersus in Namibia consisted mainly of sardine Sardinops sagax in the 1950s. Since the collapse of pelagic fish stocks in the 1970s, birds fed mainly on bearded (pelagic) goby Sufflogobius bibarbatus, a low-energy prey...

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Cross-shelf observations of diet and diel feeding behaviour of the bearded goby Sufflogobius bibarbatus off Namibia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Hundt --- Department of Biology, Norway AC Utne-Palm --- Department of Biology, Norway MJ Gibbons --- Department of Biodiversity and Conservation Biology, South Africa

The diet of the bearded goby Sufflogobius bibarbatus was studied at two 48 h stations off the Namibian coast. The inner station (120 m) was characterised by a deep layer of low-oxygen bottom water (<0.5 ml DO l−1 or <10%...

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Accumulation of diarrhetic shellfish poisoning toxins in the oyster Crassostrea gigas and the mussel Choromytilus meridionalis in the southern Benguela ecosystem

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GC Pitcher --- Branch: Fisheries Management, Department of Agriculture, South Africa B Krock --- , Germany AD Cembella --- , Germany

Diarrhetic shellfish poisoning (DSP) poses a significant threat to the safe consumption of shellfish in the southern Benguela ecosystem. The accumulation of DSP toxins was investigated in two cultivated bivalve species, the Pacific oyster Crassostrea gigas and the mussel Choromytilus...

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Investigations into the diet and feeding ecology of the bearded goby Sufflogobius bibarbatus off Namibia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RB Cedras --- Department of Biodiversity and Conservation Biology, South Africa A-GV Salvanes --- Department of Biology, Norway MJ Gibbons --- Department of Biodiversity and Conservation Biology, South Africa

The bearded goby Sufflogobius bibarbatus has come to replace sardine Sardinops sagax in the diets of many top predators within the marine environment off Namibia, and it is playing a key role within the region's foodweb. Previously published information on...

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Prioritising range-wide scientific monitoring of the Cape fur seal in southern Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: SP Kirkman --- Department of Environmental Affairs, South Africa WH Oosthuizen --- Department of Environmental Affairs, South Africa MA Meÿer --- Department of Environmental Affairs, South Africa SM Seakamela --- Department of Environmental Affairs, South Africa LG Underhill --- Department of Zoology, South Africa

The range of the Cape fur seal Arctocephalus pusillus pusillus population largely coincides with the region of the cold, nutrient-rich Benguela Current Large Marine Ecosystem (BCLME) adjoining the west coast of South Africa, Namibia and Angola. Range-wide scientific monitoring of...

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The seaweeds of Angola: the transition between tropical and temperate marine floras on the west coast of southern Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RJ Anderson --- Branch: Fisheries, Department of Agriculture, Forestry and Fisheries, South Africa JJ Bolton --- Botany Department and Marine Research Institute, South Africa AJ Smit --- School of Biological and Conservation Sciences, South Africa D da Silva Neto --- Departamento de Ambiente do Instituto Nacional de Investigação Pesqueira (INIP), Angola

The seaweed flora of Angola is relatively poorly known. Most of the 124 records listed for the country come from a 1974 British Natural History Museum expedition to the central and southern parts of that country. Previous biogeographic studies treated...

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Spawning strategies and transport of early stages of the two Cape hake species, Merluccius paradoxus and M. capensis, in the southern Benguela upwelling system

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: B Grote --- , Germany EK Stenevik --- , Norway W Ekau --- , Germany HM Verheye --- Oceans and Coasts Research, Department of Environmental Affairs, South Africa MR Lipiński --- Branch: Fisheries, Department of Agriculture, South Africa W Hagen --- Marine Zoology, Germany

Seasonal and short-term variability of environmental parameters influence the spawning strategies of fish species. In this study, the spawning strategies and the transport of early stages of the two Cape hake species off South Africa were investigated. Distribution of eggs...

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St Helena Bay (southern Benguela) then and now: muted climate signals, large human impact

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Hutchings --- Department of Environmental Affairs, South Africa A Jarre --- Marine Research (MA-RE) Institute, South Africa T Lamont --- Department of Environmental Affairs, South Africa M van den Berg --- Department of Environmental Affairs, South Africa SP Kirkman --- Department of Environmental Affairs, South Africa

The development of suitable reference states for ecosystem-based management requires documentation of changes in structure and functioning of marine ecosystems, including assessment of the relative importance of bottom-up and top-down processes as drivers of change. We used monitoring data available...

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Pygmy right whale Caperea marginata records from Namibia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RH Leeney --- Namibian Dolphin Project, Namibia K Post --- Natural History Museum, The Netherlands PB Best --- Mammal Research Institute, South Africa CJ Hazevoet --- Unidade de Zoologia, Rua da Junqueira, Portugal SH Elwen --- Namibian Dolphin Project, Namibia

All known records of pygmy right whales Caperea marginata in Namibia since 1978 are summarised for the first time, including 12 strandings (live and recently dead animals) and skeletal remains from at least eight more individuals. The majority of strandings...

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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 Cloete

The 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...

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Evidence of carbon transport between shelf and slope waters in the Benguela upwelling system

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Swart HN Waldron L Hutchings

The world ocean is pivotal in the global carbon cycle and, subsequent to anthropogenic loading of the atmosphere with CO2, its ability to sequestrate photosynthetically-fixed carbon is important with respect to our ability to predict climate change. A study of...

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Cross-shelf biogeochemical characteristics of sediments in the central Benguela and their relationship to overlying water column hypoxia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK van der Plas PMS Monteiro A Pascall

Data from two cross-shelf sediment sampling cruises were used to explain reasons for the sediment biogeochemical variability in respect of carbon, nitrogen and sulphur, and how the cycling of these elements governs the biogeochemistry of the overlying water through their...

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Application of a chlorophyll index derived from satellite data to investigate the variability of phytoplankton in the Benguela ecosystem

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: H Demarcq R Barlow L Hutchings

The spatial and temporal variability in phytoplankton biomass in the Benguela ecosystem was investigated over an 8-year period using a chlorophyll index (Chl Index) derived from low resolution SeaWiFS ocean colour data. Monthly composite images revealed that the surface chlorophyll...

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A note on the diet and feeding of Chrysaora hysoscella in Walvis Bay Lagoon, Namibia, during September 2003

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BA Flynn MJ Gibbons

The diet of Chrysaora hysoscella was investigated from 55 specimens caught near the surface throughout 24h in Walvis Bay Lagoon, Namibia, during September 2003. The diet was diverse, ranging from dinoflagellates to carideans, and included abundant benthic species (adults and...

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Escapement of Cape hakes under the fishing line of the Namibian demersal sampling trawl

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: T Jørgensen A Engås E Johnsen T Iilende P Kainge P Schneider

Swept area surveys in Namibian waters provide input data to the stock assessment model. To evaluate the model's predictions, it is important to understand the catch efficiency of sampling trawls. The objective of this study was to establish whether Cape...

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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 Lutjeharms

Cape 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...

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Application of the sequential t-test algorithm for analysing regime shifts to the southern Benguela ecosystem

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JAE Howard A Jarre AE Clark CL Moloney

Long-term ecosystem changes, such as regime shifts, have occurred in several marine ecosystems world-wide. Multivariate statistical methods have been used to detect such changes. A new method known as the sequential t-test algorithm for analysing regime shifts (STARS) is applied...

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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 Field

Hypotheses 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...

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Comparing internal and external drivers in the southern Benguela and the southern and northern Humboldt upwelling ecosystems

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: LJ Shannon S Neira M Taylor

Trophic models of three upwelling ecosystems, the southern Benguela (South African), southern Humboldt (Chilean) and northern Humboldt (Peruvian) systems, have been fitted to catch, abundance and fishing mortality time-series. Three drivers were considered during the model fitting: internal forcing by...

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Changes in the trophic structure of the southern Benguela before and after the onset of industrial fishing

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KE Watermeyer LJ Shannon CL Griffiths

Despite a human presence in the Benguela region for at least one million years, exploitation of marine resources by European seafarers only began in earnest in the 1400s. Ecopath with Ecosim was used to construct and compare mass-balanced foodweb models...

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Changes in the trophic structure of the northern Benguela before and after the onset of industrial fishing

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KE Watermeyer LJ Shannon J-P Roux CL Griffiths

Exploitation of marine resources has been occurring in the northern Benguela ecosystem for centuries. Understanding the cumulative long-term effects of this exploitation is important toward effective management of the modern system. Retrospective mass-balanced models of the ecosystem have been constructed,...

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Does vertical migratory behaviour retain fish larvae onshore in upwelling ecosystems? A modelling study of anchovy in the southern Benguela

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: C Parada C Mullon C Roy P Fréon L Hutchings CD van der Lingen

A spatially explicit individual-based model (IBM) forced by 3D temperature and current fields simulated by a hydrodynamic model of the southern Benguela upwelling region was used to test two hypotheses concerning the role of diel vertical migration (DVM) by Cape...

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Confirmed identification of gymnodimine in oysters from the west coast of South Africa by liquid chromatography–tandem mass spectrometry

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: B Krock GC Pitcher J Ntuli AD Cembella

Mussels Choromytilus meridionalis and oysters Crassostrea gigas were suspended from a mooring off Lambert's Bay, South Africa, to study the kinetics of lipophilic phycotoxin accumulation and detoxification. The shellfish were subsequently harvested daily over approximately three weeks and analysed for...

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Extension of PIRATA in the tropical South-East Atlantic: an initial one-year experiment

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Rouault J Servain CJC Reason B Bourlès MJ Rouault N Fauchereau

The Pilot (later termed Prediction) and Research Moored Array in the Tropical Atlantic (PIRATA) programme, developed as a multinational network by Brazil, France and the USA, has deployed and maintained an array of 17 Autonomous Temperature Line Acquisition Systems (ATLAS)...

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Use of environmental parameters to explain the variability in spawnerrecruitment relationships of Namibian sardine Sardinops sagax

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: CH Kirchner --- National Marine Information and Research Centre, Namibia CH Bartholomae --- National Marine Information and Research Centre, Namibia A Kreiner --- National Marine Information and Research Centre, Namibia

This study attempts to explain the variability in recruitment of sardine in the northern Benguela and to develop potential models by including environmental information to predict recruitment. Two different recruitment and spawner number datasets were available: a VPA-developed dataset, for...

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Ontogenetic and seasonal shifts in the diet of Diplodus cervinus hottentotus (Pisces: Sparidae) in southern Angola

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AC Winkler --- Department of Ichthyology and Fisheries Science, South Africa CV Santos --- Faculdade Ciências da, Angola WM Potts --- Department of Ichthyology and Fisheries Science, South Africa

Dietary information on the zebra seabream Diplodus cervinus hottentotus was collected between March 2011 and February 2012 in southern Angola. Invertebrates dominated the diet of D. c. hottentotus (61.08% ranking index [RI]) and comprised Polychaeta (38.9% RI), Amphipoda (13.2% RI),...

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A preliminary molecular phylogeny of the Namib Desert darkling beetles (Tenebrionidae)

Item type: Journal Article • Journal: African Zoology • Authors: J. Steckel --- Department of Ecology, Germany M.L. Penrith --- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, South Africa J. Henschel --- Gobabeb Training and Research Centre, Namibia R. Brandl --- Department of Ecology, Germany J. Meyer --- Department of Ecology, Germany

A systematic classification of Namib Desert darkling beetles (Coleoptera: Tenebrionidae) based on morphological characters is complicated as strong selection pressures exerted by desert conditions have led to a suite of convergent morphological characteristics. Here we present a first and preliminary...

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Diel effects on bottom-trawl survey catch rates of shallow- and deep-water Cape hakes Merluccius capensis and M. paradoxus off Namibia, using solar zenith angle

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: P Kainge --- National Marine Information and Research Centre (NatMIRC), Namibia K Wieland --- Section for Monitoring and Data, Institute of Aquatic Resources, Denmark J Feekings --- Section for Ecosystem based Marine Management, Denmark

Diel patterns in survey trawl catches for the Cape hakes Merluccius capensis and M. paradoxus off Namibia were studied in order to examine the effect of diel bias on catchability, and its implication for survey abundance estimation and the consistency...

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First account of the metazoan parasite fauna of oilfish Ruvettus pretiosus Cocco, 1829 (Perciformes: Gempylidae) in South African waters

Item type: Journal Article • Journal: African Zoology • Authors: Irfan Nunkoo --- Department of Biological Sciences, South Africa Mark J Weston --- Department of Biological Sciences, South Africa Cecile C Reed --- Department of Biological Sciences, South Africa Carl D van der Lingen --- Marine Research Institute and Department of Biological Sciences, South Africa Sven Kerwath --- Department of Biological Sciences, South Africa

Parasites are an important but neglected component of ecosystems that can be used as indicators of host biology and ecology. In the present study, the metazoan parasite assemblage of Ruvettus pretiosus, an understudied but widely distributed predatory gempylid, caught off...

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Population connectivity of an overexploited coastal fish, Argyrosomus coronus (Sciaenidae), in an ocean-warming hotspot

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Henriques --- Evolutionary Genomics Group, Department of Botany and Zoology, South Africa WM Potts --- Department of Ichthyology and Fisheries Science, South Africa CV Santos --- Faculdade de Ciências da Universidade Agostinho Neto (FCUAN), Angola WHH Sauer --- Department of Ichthyology and Fisheries Science, South Africa PW Shaw --- Department of Ichthyology and Fisheries Science, South Africa

The West Coast dusky kob Argyrosomus coronus is a commercially exploited fish with a distribution confined to the Angola–Benguela Frontal Zone (ABFZ) of the southeastern Atlantic Ocean. A previous study revealed that during a recent period of local warming the...

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The bivalve Lembulus bicuspidatus may enhance denitrification in shelf sediment at the Angola–Benguela Frontal Zone

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Neumann --- University of Hamburg, Institute for Geology, Germany A Flohr --- Leibniz Center for Tropical Marine Ecology, Germany

We collected living individuals of the bivalve Lembulus bicuspidatus, which shows an unusual preference for the oxygen-deficient habitat found at the Angola–Benguela Frontal Zone of the southeastern Atlantic. With a series of incubation experiments with 15N-labelled nitrate as a tracer...

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Environmental responses of jellyfish polyps as drivers of medusa populations off the coast of Namibia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Ziegler --- Department of Biodiversity and Conservation Biology, South Africa MJ Gibbons --- Department of Biodiversity and Conservation Biology, South Africa

Jellyfish populations in the southeastern Atlantic off the coast of Namibia have increased subsequent to the decline of small pelagic fisheries at the end of the 1960s, although the environment there has also become warmer and the waters off Walvis...

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Environmental influence on phytoplankton communities in the northern Benguela ecosystem

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Barlow --- , South Africa T Lamont --- , South Africa D Louw --- , Namibia M-J Gibberd --- , South Africa R Airs --- , United Kingdom A van der Plas --- , Namibia

An investigation of surface phytoplankton communities was undertaken on the shelf of the northern Benguela upwelling ecosystem during austral autumn (May) and spring (September), along latitudinal transects at 20° S and 23° S, from 2 to 70 nautical miles offshore,...

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Describing gonad development and gametogenesis in southern Africa’s endemic box jellyfish Carybdea branchi (Cubozoa, Carybdeidae)

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Mohamed --- Department of Biodiversity and Conservation Biology, South Africa H Skrypzeck --- Department of Biodiversity and Conservation Biology, South Africa MJ Gibbons --- Department of Biodiversity and Conservation Biology, South Africa

Information on the reproductive development of species of box jellyfish (class Cubozoa) is poor globally, despite their significance as potent stingers and worrying projections about range expansions. While most species are confined to tropical and subtropical waters, the South African...

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A snapshot assessment of the diet of Cape fur seals Arctocephalus pusillus pusillus at Ilha dos Tigres, Angola

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Winkler --- Department of Ichthyology and Fisheries Science, South Africa S Mannheim --- Department of Ichthyology and Fisheries Science, South Africa A-R Childs --- Department of Ichthyology and Fisheries Science, South Africa C Santos --- Biologia Faculdade de Ciências, Angola C de Beer --- Department of Ichthyology and Fisheries Science, South Africa MJ Smale --- Department of Zoology and Institute for Coastal and Marine Research, South Africa WM Potts --- Department of Ichthyology and Fisheries Science, South Africa

The population of Cape fur seal Arctocephalus pusillus pusillus at Ilha dos Tigres off the coast of southern Angola is expanding. Until now the only available biological information on the population has been its demographic parameters, and this insufficiency has...

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The status and conservation of the Cape Gannet Morus capensis

Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Richard B Sherley --- Environment and Sustainability Institute/Centre for Ecology and Conservation, United Kingdom Robert JM Crawford --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Bruce M Dyer --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Jessica Kemper --- African Penguin Conservation Project, Namibia Azwianewi B Makhado --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Makhudu Masotla --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Lorien Pichegru --- DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, Department of Biological Sciences, South Africa Pierre A Pistorius --- DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, Department of Biological Sciences, South Africa Jean-Paul Roux --- Ministry of Fisheries and Marine Resources, Namibia Peter G Ryan --- DST-NRF Centre of Excellence at the FitzPatrick Institute of African Ornithology, Department of Biological Sciences, South Africa Desmond Tom --- Ministry of Fisheries and Marine Resources, Namibia Leshia Upfold --- Department of Environment, Forestry and Fisheries (DEFF), South Africa Henning Winker --- Department of Environment, Forestry and Fisheries (DEFF), South Africa

The Cape Gannet Morus capensis is one of several seabird species endemic to the Benguela upwelling ecosystem (BUS) but whose population has recently decreased, leading to an unfavourable IUCN Red List assessment. Application of ‘JARA’ (‘Just Another Red-List Assessment,’ a...

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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 Africa

The 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...

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Application of a general methodology to understand vulnerability and adaptability of the fisheries for small pelagic species in the Benguela countries: Angola, Namibia and South Africa

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: KL Cochrane --- , South Africa K Ortega-Cisneros --- , South Africa JA Iitembu --- , Namibia CI dos Santos --- , Angola WHH Sauer --- , South Africa

The fisheries for small pelagic species in Angola, Namibia and South Africa fulfil important social and economic roles but have undergone substantial changes in recent years, some of which are likely to be related to climate change. This assessment of...

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Comparison of the particle size distributions of sediment collected from sandy seafloor using a Van Veen grab and cone dredge

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: GM van der Heever --- , South Africa LJ Atkinson --- , South Africa CEO von der Meden --- , South Africa

Sediment particle size is an important environmental parameter that influences benthic species composition and is frequently used in habitat and ecosystem classification systems. In South Africa, benthic grabs are regularly used to collect seafloor sediment samples for particle size analysis...

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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 Africa

A 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...

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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 Africa

The 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...

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Geographical and seasonal patterns in the diet of Cape fur seals Arctocephalus pusillus pusillus in Namibia, based on extensive scat analyses

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: DN Mwaala --- University of Namibia, Namibia MR Wilhelm --- University of Namibia, Namibia SP Kirkman --- Fisheries and the Environment (DFFE): Branch Oceans and Coasts, South Africa J-P Roux --- Ministry of Fisheries and Marine Resources, Namibia

Namibia's population of Cape fur seals Arctocephalus pusillus pusillus is a major constituent of top predator biomass in the northern Benguela upwelling system. Understanding their diet is key to comprehending their role in the ecosystem and potential drivers of recent...

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Predation on the St Joseph Callorhinchus capensis by Cape fur seals Arctocephalus pusillus pusillus in Namibia

Item type: Journal Article • Journal: African Journal of Marine Science • Authors: RH Leeney --- Namibia Nature Foundation, Namibia N Dreyer --- Ocean Conservation Namibia, Namibia

Chondrichthyans form an important part of marine food webs as top predators and mesopredators. However, little is known about chondrichthyans in Namibian waters and the roles they play in ecosystem function. During efforts to disentangle Cape fur seals Arctocephalus pusillus...

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Diversity, distribution and knowledge gaps of Polychaeta on the continental shelf of southern Namibia

Item type: Journal Article • Journal: African Zoology • Authors: Amoré Malan --- , South Africa Aiden Biccard --- , South Africa Jessica Dawson --- , South Africa Robyn Payne --- , South Africa Kevin Schmidt --- , South Africa Kirti N Gihwala --- , South Africa Ken Hutchings --- , South Africa Deon Louw --- , Namibia Josef Shikeva --- , Namibia Blessing Kamwi --- , Namibia Lapaka Kaimbi --- , Namibia Julien Vumazonke --- , Namibia Megameno Mutaleni --- , Namibia Thomas Shannon --- , United Kingdom Sarah Chordekar --- , United Kingdom Vere Ross-Gillespie --- , United Kingdom

This study investigated the diversity, composition and distribution patterns of polychaete macrofauna inhabiting unconsolidated sediments on the continental shelf of southern Namibia. During the austral summer of 2021, 910 Van Veen grab samples were collected from 91 sites in water...

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High adult mortality of African Penguins Spheniscus demersus in South Africa after 2004 was likely caused by starvation

Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Robert JM Crawford --- Fisheries and the Environment, South Africa Richard B Sherley --- Environment and Sustainability Institute/Centre for Ecology and Conservation, University of Exeter, United Kingdom Lynne J Shannon --- University of Cape Town, South Africa Alistair M McInnes --- BirdLife South Africa, South Africa Tegan Carpenter-Kling --- Institute for Coastal and Marine Research, Nelson Mandela University, South Africa Azwianewi B Makhado --- Fisheries and the Environment, South Africa

From 2004–2011, following the collapse of sardine Sardinops sagax, a main food for African Penguins Spheniscus demersus, to < 25% of its maximum recorded abundance, survival of penguins breeding at Dassen and Robben islands, north of Cape Town, South Africa...

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