A5019835913- Marine and fisheries research
- Marine animal studies overview
- Coral and Marine Ecosystems Studies
- Fish Ecology and Management Studies
- Marine Bivalve and Aquaculture Studies
- Avian ecology and behavior
- Fish Biology and Ecology Studies
- Underwater Acoustics Research
- Ichthyology and Marine Biology
- Marine and coastal plant biology
- Coastal and Marine Management
- Marine and environmental studies
- Marine Invertebrate Physiology and Ecology
- Genetic and phenotypic traits in livestock
- Oceanographic and Atmospheric Processes
- Marine Biology and Ecology Research
- Aquatic Ecosystems and Biodiversity
- Maritime Security and History
- Food Industry and Aquatic Biology
- Marine and coastal ecosystems
- Remote Sensing and LiDAR Applications
- Isotope Analysis in Ecology
- Evolutionary Game Theory and Cooperation
- Image Processing and 3D Reconstruction
- Identification and Quantification in Food
University of the Western Cape
2024
Department of Agriculture, Land Reform and Rural Development
2013
University of Cape Town
2006
Port Elizabeth Provincial Hospital
1996
Summary Remote‐sensing measurements of marine primary productivity are widely used to predict the distribution and movements top predators, despite fact that predators do not feed directly on phytoplankton but several trophic levels higher up food chain. To test for potential links between top‐predator feeding hotspots, we assessed spatial match–mismatch across four Benguela upwelling zone (south‐east Atlantic). The chain studied consisted phytoplankton, zooplankton (copepods), pelagic fish...
Abstract Coetzee, J. C., van der Lingen, C. D., Hutchings, L., and Fairweather, T. P. 2008. Has the fishery contributed to a major shift in distribution of South African sardine? – ICES Journal Marine Science, 65: 1676–1688. A sardine (Sardinops sagax) has resulted significant spatial mismatch fishing effort vs. fish abundance recent years. The started on west coast during 1940s, processing capacity there increased rapidly. This trend together with increases annual landings continued up...
Abstract Cape anchovy Engraulis encrasicolus spawners in the southern Benguela showed an eastward shift their distribution on Agulhas Bank that occurred abruptly 1996 and has since persisted. We assessed whether this was environmentally mediated by examining sea surface temperature data from different regions of Bank, which inner shelf to east became 0.5°C colder than previous years remained way. In addition, signals, coherent with recorded temperatures, were also found atmospheric pressure...
Abstract The N ans C lim project (2010–2013) represented a regional collaboration to assess the effects of climate on B enguela dynamics. Based in situ (since 1960s amibia and S outh A frica 1985 ngola) satellite 1980s) observations, focussed four subsystems, namely ngola subtropical, northern upwelling, southern upwelling gulhas ank. This contribution summarizes findings for selected key questions, ranging from changes physico‐chemical habitats, plankton, pelagic demersal fish communities,...
The use of a shoal analysis and patch estimation system (SHAPES) to analyse hydro-acoustic data is discussed. SHAPES was used detect characterise sardine schools from four echo integration surveys off the coast South Africa. Methods school detection characterisation, assumptions made corrections applied variables are presented. Measurements morphology internal features discussed compared other relevant works. Significant relationships were established, both between measures density...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 350:127-136 (2007) - DOI: https://doi.org/10.3354/meps07128 Foraging behaviour and energetics of Cape gannets Morus capensis feeding on live prey fishery discards in Benguela upwelling system Lorien Pichegru1,2,*, Peter G. Ryan2, Carl D. van der Lingen3, Janet Coetzee3, Yan Ropert-Coudert4, David Grémillet1,2...
Pelagic ecosystems support a significant and vital component of the ocean's productivity biodiversity. They are also heavily exploited and, as result, focus numerous spatial planning initiatives. Over past decade, there has been increasing enthusiasm for protected areas tool pelagic conservation, however, few have implemented. Here we demonstrate an approach to plan that address physical biological dynamics typical realm. Specifically, provide example integrates benthic conservation in...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 473:291-301 (2013) - DOI: https://doi.org/10.3354/meps10070 Influence of local and regional prey availability on breeding performance African penguins Spheniscus demersus Richard B. Sherley1,3,9,*, Les G. Underhill1,2, Barbara J. Barham4, Peter Barham2,5, Janet C. Coetzee6, Robert M. Crawford2,7, Bruce Dyer7,...
Abstract This paper provides an introduction to, and overview of, the natural phenomenon known as KwaZulu-Natal sardine run. Previous literature on this topic hypotheses about reasons why, mechanisms how, run occurs are briefly synthesised described. Papers contributing to suite that detail more recent work a variety of aspects run, ranging from physical oceanography through biology ecology socio-economic ecological consequences, outlined. Such studies will lead improved understanding...
Summary Climate change and fishing impact marine ecosystems, potentially modifying the availability of small pelagic fish to top predators. Some seabirds that primarily rely upon these resources have switched feeding on fishery waste. It has therefore been argued might become dependent this artificial resource. To test hypothesis, we studied foraging behaviour Cape gannets M orus capensis breeding off coast South Africa using high‐resolution Global Positioning System‐tracking in relation...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 505:281-293 (2014) - DOI: https://doi.org/10.3354/meps10762 Changes in prey availability impact foraging behaviour and fitness of Cape gannets over a decade Lea A. Cohen1,*, Lorien Pichegru2,3, David Grémillet1,4, Janet Coetzee5, Leshia Upfold6, Peter G. Ryan1 1DST/NRF Centre Excellence at Percy FitzPatrick...
Abstract Seabirds are upper trophic level predators, and often highly sensitive to changes in the availability of their prey. Altered prey assemblages resulting from fluctuations oceanographic conditions may be mirrored by shifts seabird diet. Long-term studies dietary change seabirds therefore provide valuable insight into nature environmental within systems which they forage. In recent decades, Agulhas region South Africa has undergone significant related warming intensification current....
Abstract Understanding the functional relationship between marine predators and their prey is vital to inform ecosystem‐based management. However, collecting concurrent data on predator behaviour at relevant scales challenging. Moreover, opportunities study these relationships in absence of industrial fishing are extremely rare. We took advantage an experimental fisheries closure how local abundance influences foraging success chick condition Endangered African penguins Spheniscus demersus...
Abstract Off South Africa, anchovy Engraulis encrasicolus and sardine Sardinops sagax are the main prey of African penguins Spheniscus demersus. The combined spawner biomass these fish increased from less than one million t in 1996 to more nine 2001 then decreased four 2005. young-of-the-year species 0.2 3.2 before falling 0.4 There was a large eastward shift distribution between 1999 number breeding Western Cape Province 18 000 pairs 30 2005 21 2006, as availability near localities. Numbers...
Abstract The biomass of small pelagic fish species off the coast South Africa has been monitored since 1984 using hydro-acoustic survey techniques. These time-series spawner and recruitment estimates form basis for management both African sardine Sardinops sagax anchovy Engraulis encrasicolus resources are central to setting annual total allowable catch levels. However, these have, most part, treated as relative indices there several biases inherent in acoustic methodology that remain...
Abstract Strategies of space occupation by anchovy and sardine populations in the southern Benguela during cruises 1994 (low biomass) 2001 (high are investigated using geostatistical tools. The spatial expansion high-density year resulted an increase number density hotspots and, case anchovy, a relative contribution mid- to intervals overall survey biomass. Variogram autocorrelation ranges were larger high-biomass year. Otherwise, similarities differences strategies between consistent years...
Abstract Hydro-acoustic surveys have been used to provide annual estimates of May recruitment and November spawner biomass the South African sardine Sardinops sagax anchovy Engraulis encrasicolus resources since 1984. These time-series abundance form backbone assessment these resources, consequently management is critically dependent on them. Upgrades survey equipment over time resulted in recent providing more accurate abundance, yet order maintain comparability across full time-series,...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 596:155-164 (2018) - DOI: https://doi.org/10.3354/meps12567 Non-stationary responses in anchovy (Engraulis encrasicolus) recruitment coastal upwelling Southern Benguela Peter van der Sleen1,2,*, Ryan R. Rykaczewski3, Brendan D. Turley3, William J. Sydeman4, Marisol García-Reyes4, Steven Bograd5, Carl...