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Marine alien species of South Africa — status and impacts
Only one species, the Mediterranean mussel Mytilus galloprovincialis, has spread extensively along the coast and caused significant ecological impacts and substantial economic benefits have also resulted from this invasion. Expand
Phytoplankton production and biomass at frontal zones in the Atlantic sector of the Southern Ocean
A high resolution study of chlorophyll a and primary production distribution was carried out in the Atlantic sector of the Southern Ocean during the austral summer of 1990–91, suggesting that the increase in biomass was probably the result of an enhancement of in situ production by selected components of the phytoplankton assemblage, rather than accumulation of cells through hydrographic forces. Expand
A review of marine phylogeography in southern Africa
This review describes the state of marine phylogeography in southern Africa, that is, the study of evolutionary relationships at the species level, or amongst closely related species, in relation to the region’s marine environment, and focuses particularly on coastal phylegeography. Expand
Zooplankton structure and grazing in the Atlantic sector of the Southern Ocean in late austral summer 1993 Part 2. Biochemical zonation
The composition, biomass, distribution and grazing impact of dominant components of the meso- and macrozooplankton community were investigated along a transect occupied in the Atlantic sector of theExpand
Gradients of intertidal primary productivity around the coast of South Africa and their relationships with consumer biomass
The large-scale gradient in intertidal productivity around the coast is strongly linked with grazer biomass and individual body size, but any effect it has on filter-feeder biomass seems subsidiary to the local effects of wave action. Expand
Trophic structure of the marine food web at the Prince Edward Islands (Southern Ocean) determined by δ13C and δ15N analysis
Findings of the present study indicate for the first time that autochthonous sources of organic matter, e.g. kelp-derived and microphytoplankton blooms, are important components of the diets of all but the zooplankon community at the sub-Antarctic Prince Edward Islands. Expand
Land-based predator impact on vertically migrating zooplankton and micronekton advected to a Southern Ocean archipelago
Combined acoustic (12 and 120 kHz) and trawling (RMT-2 and Bongo net) surveys in offshore waters of the Prince Edward Archipelago revealed diurnal vertical migration of major prey species (theExpand
Distribution of surface zooplankton and seabirds across the Southern Ocean
It is suggested that appropriate food availability rather than water temperature is important for the determination of seabird distribution and the ecological importance of the recently described frontal zone associated with the northern boundary of the maximum winter expansion of sea ice is confirmed. Expand
Biogeographic and nearshore-offshore trends in isotope ratios of intertidal mussels and their food sources around the coast of southern Africa
There are broad differences in oceanography and primary production around the south- ern African coast that are likely to give rise to major differences in trophic pathways. Stable isotope ratiosExpand