SBCTS-A: North West Coast
southern Benguela Current
Latitude:   -30.5759     Longitude:   16.5870

 Associated Investigators:
Jenny Huggett ,
Hans Verheye  

Related Time Series:
[ North West Coast SBCTS-A ]   [ Central West Coast SBCTS-B ]   [ South West Coast SBCTS-C ]   [ Western Agulhas Bank SBCTS-D ]   [ Agulhas Bank Copepod Time Series (ABCTS) ]  

The Benguela system is one of the four major eastern boundary upwelling systems of the world, characterised by high productivity and large pelagic fish populations. The Southern Benguela extends from the Orange River in the north (the boundary between South Africa and Namibia) to Cape Agulhas on the south coast of South Africa, the approximate longitude of the (warm) Agulhas Current retroflection. Upwelling-favourable, south-easterly winds reach a maximum during austral spring and summer, with the upwelling season extending from September to March. The system has been sub-divided into four areas for spatial analysis (Huggett et al. 2009). Three regions on the West Coast correspond to upwelling cells as defined by Shannon and Nelson (1996): the Namaqua (Hondeklipbaai) cell in the extreme north, designated the North West Coast (NWC), extending from the mouth of the Orange River to 31 S; the Columbine cell, designated the Central West Coast (CWC), extending from 31 S to Cape Columbine; and the Cape Peninsula cell in the south, called the South West Coast (SWC), extending from Cape Columbine to Cape Point. The fourth area, the Western Agulhas Bank (WAB), extends eastwards from Cape Point to Cape Agulhas on the South Coast. The West Coast is an important nursery area for pelagic fish in winter, whereas the adult fish spawn mainly in summer on the South Coast. Biannual monitoring of zooplankton, with a focus on copepods as important prey items for pelagic fish, was initiated in 1988. Vertical bongo net (200-Aum mesh) hauls to a depth of 200 m were used to collect zooplankton along stratified random transects crossing the continental shelf, perpendicular to the coast, during hydro-acoustic pelagic surveys in late spring/early summer (November/December) and late autumn/early winter (May/June). All copepods were counted and identified to stage, species or category, as described in Huggett et al. (2009).

REFERENCES:

Shannon LV, Nelson G (1996) The Benguela: large scale features and processes and system variability. In: Wefer G, Berger WH, Siedler G, Webb D (Eds) The South Atlantic: Present and Past Circulation. Springer-Verlag, Berlin, pp. 163-210.

Huggett JA, Verheye HM, Escribano R, Fairweather T (2009) Copepod biomass, size composition and production in the Southern Benguela: spatio-temporal patterns of variation, and comparison with other eastern boundary upwelling systems. Progress in Oceanography 83: 197-207.