A5022137950- Marine Invertebrate Physiology and Ecology
- Marine Biology and Ecology Research
- Marine and fisheries research
- Coral and Marine Ecosystems Studies
- Marine and environmental studies
- Marine Ecology and Invasive Species
- Fish Ecology and Management Studies
- Marine and coastal plant biology
- Marine Sponges and Natural Products
- Cephalopods and Marine Biology
- Fish Biology and Ecology Studies
- Aquatic Ecosystems and Phytoplankton Dynamics
- Genetic diversity and population structure
- Evolutionary Game Theory and Cooperation
- Marine Bivalve and Aquaculture Studies
- Ichthyology and Marine Biology
- Marine and coastal ecosystems
- Parasite Biology and Host Interactions
- Isotope Analysis in Ecology
- Fish biology, ecology, and behavior
- Genetics, Bioinformatics, and Biomedical Research
- Crustacean biology and ecology
- Species Distribution and Climate Change
- Identification and Quantification in Food
- Coastal and Marine Management
University of the Western Cape
2015-2025
Bell (Canada)
2025
City of Cape Town
2025
New Frontier
2000
University of Cape Town
1986-1997
Changes in two contrasting ecosystems of the Benguela upwelling region, one dominated at mid-trophic level by jellyfishes (Namibia, northern ecosystem, where small pelagic fish abundance has been severely depleted) and still fishes (South Africa, southern Benguela) were compared an effort to determine ecosystem trajectories under different exploitation regimes.The role (clupeoids) was highlighted context their importance maintaining interactions marine ecosystems.In particular, we examined...
Since the collapse of pelagic fisheries off southwest Africa in late 1960s, jellyfish biomass has increased and structure Benguelan fish community shifted, making bearded goby (Sufflogobius bibarbatus) new predominant prey species. Despite predation pressure a harsh environment, gobies are thriving. Here we show that physiological adaptations antipredator foraging behaviors underpin success these fish. In particular, body-tissue isotope signatures reveal consume sulphidic diatomaceous mud,...
S. dandelenae sp. nov. is described from the west coast of South Africa and occurs at depths 80-500 m among unconsolidated sediments. Specimens can reach 40 cm in length some areas off Africa, up to 18 tons/km2 be collected a single demersal trawl. Morphologically, sponge straw yellow, massive with rounded lobes has velvety surface: it characterized by subradiate, irregular reticulation bundles tylostyles tylostrongyles. have three size classes largest tylostyle lengths being 516 μm (441-614...
Abstract. Jellyfish are increasingly recognised as important components of the marine ecosystem, yet their specific role is poorly defined compared to that other zooplankton groups. This paper presents first global ocean biogeochemical model includes an explicit representation jellyfish and uses gain insight into influence on plankton community. The Plankton Type Ocean Model (PlankTOM11) groups organisms functional types (PFTs). PFT parameterised here based our synthesis observations growth,...
Tethya samaaii Ribeiro & Muricy, 2011 is a massive, irregularly globular or sub-spherical sponge with basal rooting processes disc-like attachment (Figure 1A). It was described from Oudekraal, on the west coast of South Africa as rubra Samaai Gibbons, 2005 based specimens collected during two surveys in 1996 (Samaai Gibbons 2005). This species later reported Algoa Bay, southeast by Waterworth et al. (2017).
Chrysaora (Pèron & Lesueur 1810) is the most diverse genus within Discomedusae, and 15 valid species are currently recognised, with many others not formally described. Since fulgida (Reynaud 1830) was first recognised as occurring off south west (SW) coast South Africa, has been variously synonymised hysoscella (Linnaeus 1767) africana (Vanhöffen 1902). Using DNA evidence alongside multivariate tools to analyse quantitative morphometric meristic data, well information from cnidome, we...
A new species of the cosmopolitan jellyfish genus Aurelia is described from coastal waters Mozambique using a combination morphological, meristic and genetic information (COI 18S). The can be separated congeners that have been recently by bell shape, number canal origins anastomoses, shape manubrium oral arms. Three types nematocysts are present in tissues both margin arms, this description cnidome will allow for future comparison. Pairwise comparisons showed mean COI divergence 4.8% within...
There has been debate in the literature recently about increases jellyfish populations response to anthropogenic change, and this attracted widespread media interest. Despite an international collaborative initiative [National Center for Ecological Analysis Synthesis (NCEAS) working group on blooms] investigate trends global numbers, interpretations from data remain ambiguous. Although is perhaps be expected given diversity of potential drivers, not helped by a general lack rigorous loose...
Sixteen species of Latrunculiidae Topsent, 1922, belonging to the genera Latrunculia du Bocage, 1869, Strongylodesma Lévi, 1969, Cyclacanthia Samaai & Kelly, 2004, 2002, are currently known from temperate waters South Africa. Extensive new sponge collections Amathole region Africa revealed existence three Tsitsikamma, T. amatholensis sp. nov., madiba and beukesi a endemic African genus Cyclacanthia, C. rethahofmeyri nov. With recent addition two Tsitsikamma Algoa Bay National Park (T....
Non-studied museum collections are hidden treasures-a source of information for various research fields. The novel taxa presented here were discovered during taxonomic examination the backlogs Bryozoa (Cheilostomata) from Iziko South African Museum. We describe one new genus, Khulisa n. gen., and nine species bryozoans Africa. are: Biflustra adenticulata sp., Aspidostoma sarcophagus ?Micropora erecta Trypostega richardi carolinae gen. et Adeonella assegai Hippomonavella lingulata Phidolopora...
Walters Shoal is a shallow seamount located on the South Madagascar Ridge, which situated approximately 833 km south of and 1,296 east Africa. Even though it penetrates euphotic zone (summit 15 m below sea surface) protected by Southern Indian Ocean Deep-Sea Fishers Association, there paucity biodiversity oceanographic data. Thus, multidisciplinary cruise was initiated in May 2014 FRS Algoa as component African Coelacanth Ecosystem Programme (III). This paper reports 11 new heteroscleromorph...
Abstract Acoustic target-strength (TS) measurements are presented for tethered and free-swimming individual Chrysaora hysoscella (Scyphozoa) Aequorea aequorea (Hydrozoa) medusae in Namibian waters. Tethered C. (17–54 cm total umbrella diameter) A. (19–28 were ensonified at 38 kHz using a portable echosounder. Mean TS values this frequency ranged from −67.3 to −52.8 dB −65.4 −50.1 aequorea. There was positive relationship between medusa diameter both species. of varied cyclically over time by...
Abstract Aim Using the genus as unit of analysis, we examine relationship between richness, distribution and life cycle strategy for all currently recognized marine Hydrozoa. Location The global environment. Methods A dataset detailing number species per mean date first description (as a proxy geographic range size) was assembled Differences in means were examined by dominant (holoplanktic, meroplanktic benthic) using nonparametric ANOVA resampling methods. Results By comparison with benthic...
Abstract Whether jellyfish are increasing or not in the global ocean is a subject of some debate, but fact remains that when they bloom, can negatively affect local economies. Despite this, there has been no robust debate about idea deliberately removing as means population control. Here, we discuss effects fishing for jellyfish, either sustainable resource and/or way to simply reduce their nuisance value, on both individual populations and ecosystem. Given drivers influencing each bloom...
Current knowledge of the community structure, life history strategies and trophodynamics euphausiids in Benguela ecosystem is synthesized. Three species dominate, Euphausia lucens over shelf region southern Benguela, hanseni outer off Namibia Nyctiphanes capensis neritic regions northern Benguela. Various models interactions between biological processes physical features are considered to explain likely mechanisms whereby these can remain spatially segregated. All three breed throughout...
AbstractRecent changes have been observed in South African marine ecosystems. The main pressures on these ecosystems are fishing, climate change, pollution, ocean acidification and mining. best long-term datasets for trends fishing but there many gaps, especially non-commercial species. Fishing varied over time, depending the species being caught. Little information exists other anthropogenic pressures. Field observations of environmental variables limited time space. Remotely sensed...
Ocean acidification may negatively affect calcifying plankton, opening ecological space for noncalcifying species. Recently, a study of climate‐forcing jellyfish reported the first analysis suggesting that there were more (generally considered group) when conditions acidic (lower pH) from one area within North Sea. We examine this suggestion number areas in Sea and beyond Northeast Atlantic using coelenterate records Continuous Plankton Recorder pH data International Council Exploration...