Hocutt, C.H.

Verheye, H.M.

Open Marine Archive

and the Angola-Benguela frontal system.
This included direct measurements of
currents, the collection of data on water
column chemistry and nutrient concen-
tration, and on the distribution of phyto-
plankton and zooplankton. The cruise
grid in Fig. 1 provides a quasi-synoptic
view of the Equatorial Current system
with its southward extension along the
coasts of Angola and Namibia.
Most of the training was conducted
aboard the Africana from May to July 1999
on two separate cruises (Cruises 2 and 3).
Cruise 2 comprised South Africa’s annual
routine pelagic fish stock assessment
survey, which provides scientific data
towards the setting of total allowable
catches of anchovy and sardine. In 1999,
this two-legged survey (Leg 1: Orange
River to Cape Point, 7–19 May; Leg 2:
Cape Point to Port Alfred, 19 May–2 June;
Fig. 2) was expanded to accommodate
trainees from the SADC region and pro-
vide training in marine electronics and
acoustic survey techniques for fishes. Its
specific objectives were to
• estimate the biomass and size structure
of anchovy and sardine recruits, and
examine their distribution and behav-
iour;
• collect biological data on pelagic fish
species;
• collect data on the distribution and
abundance of anchovy and sardine
eggs;
• examine the distribution and abun-
dance of plankton in relation to the
environment and to the distribution
and condition of recruits; and
• collect hydrographic data on water col-
umn properties and water flows to
study their influence on the above.
Cruise 3 started on 21 June 1999, when
the Africana left Cape Town for Walvis
Bay, the first of four legs that was to see
her conducting research northward past
the Angola-Benguela Front to Luanda,
before returning to Cape Town in early
August. The primary scientific objective
of Cruise 3, Leg 1 (21 June–1 July 1999;
Fig. 3) was based on various project pro-
posals received to examine the fisheries
environment of the region, and thus to
provide support to resource-orientated
work. This cruise leg was therefore
planned to investigate differences in the
oceanography between the southern
Benguela off South Africa and the central
Benguela off Namibia, south of Walvis
Bay, as well as the exchange of water
between these two sub-systems due to
ocean currents. Specific scientific objec-
tives were to study the physical, chemical
and biological oceanography in the
southern and central Benguela, in sup-
port of improving our knowledge of the
fisheries environment; provide ground-
truthing for satellite remote sensing of
ocean colour (SeaWIFS); support regional
monitoring work; and investigate ocean-
ographic linkages between South Africa
and Namibia.
The Africana left Walvis Bay on 1 July
1999 to conduct Leg 2 of Cruise 3 on the
Namibian shelf up to the Cunene River
(Fig. 4). The main scientific objectives
were to (a) investigate the coastal current
and undercurrent systems and the
hydrography along the Namibian coast;
(b) investigate the distribution and trans-
port of the plankton community, and
their relationship to the prevailing cur-
rents and hydrography; and (c) study the
development, short-term variability and
position of the Angola-Benguela Front.
The Africana and her crew carried out
their duties until propulsion problems
were encountered on 10 July north of the
Cunene River, forcing her back to Walvis
Bay. Moving primarily on her bow thrust-
ers, sometimes at speeds not greater than
2 knots, she reached Walvis Bay on
Wednesday 14 July.
Within hours, in an exemplary model of
regional cooperation, Marine and Coastal
Management Coordination in Cape
Town and the Namibian Ministry of Fish-
eries and Marine Resources began to
make plans to continue the shipboard
training programme; the Algoa and the
Welwitchia took over the research/training
duties of the Africana. The Algoa arrived in
Walvis Bay on the evening of 20 July, and
the Welwitschia had just returned to port
following an orange roughy survey.
The Welwitchia sailed again on 23 July
and provided oceanographic training
during the northward Leg 3 of Cruise 3 to
Luanda (Fig. 5). Originally, the overall
scientific objective was to investigate the
nearshore current systems on the Ango-
lan shelf (between Luanda and the
Cunene River) and their influence on the
distribution and transport of plankton
communities, and to study the develop-
ment and position of the Angola-Benguela
frontal system. Since the replacement
vessel was much smaller, however, fewer
scientists could be accommodated and
less scientific equipment was available,
hence it was no longer possible to fulfil
all objectives. The scientific goals of the
revised programme (23 July–3 August)
BENEFIT Marine Science South African Journal of Science 97, May/June 2001 197
Fig. 2. Track chart and station positions of FRS
Africana during Cruise 2 (Legs 1 and 2) (southwest
Cape coast of South Africa) in May/June 1999.
Fig. 3. Track chart and station positions of FRS
Africana during Leg 1 (Cape Town–Walvis Bay) of
Cruise 3 in June/July 1999.
Fig. 4. Track chart and station positions of FRS
Africana during Leg 2 (Walvis Bay–Angola-Benguela
Front–Walvis Bay) of Cruise 3 in July 1999.
were therefore to (a) monitor environ-
mental conditions such as temperature,
salinity and dissolved oxygen; (b) deploy
ARGOS satellite-tracked drifters off the
Angolan coast; (c) collect water column
samples for the analysis of nutrients and
hydrogen sulphide; (d) sample popula-
tions of zooplankton and ichthyo-
plankton; and (e) map the distributions of
nutrients and chlorophyll a from the
underway scientific seawater supply.
For the completion of Leg 4 of Cruise 3,
equipment from the Africana was trans-
ferred to the Algoa before both vessels
sailed to Cape Town on 21 July, with
the Algoa conducting training in fishery
resources (Fig. 6). The main objectives of
this leg were instruction in acoustic sur-
vey methods and monitoring interactions
between the fish and their environment.
The cruise included two 30-h experiments
studying the diel migration behaviour of
hake and covered an acoustic survey
between Lüderitz and the Orange River
mouth, an area seldom surveyed. In
addition, plankton and hydrological
sampling, and the recovery of a current
meter deployed during an earlier leg of
the BENEFIT cruises, were also included
in the revised cruise programme.
Following the cruises, 30 of the trainees
were invited to Cape Town in November
1999 to participate in a workshop devoted
to analysing the database that had been
assembled at sea. The scientific and tech-
nical staff of the Branch: Marine and
Coastal Management Coordination are to
be complemented for organizing this
workshop as a crucial antecedent to the
10th Southern African Marine Science
Symposium (SAMSS) held at the Wilder-
ness, South Africa, during 22–26 Novem-
ber 1999. SAMSS provided the BENEFIT
trainees and trainers an opportunity to
present the scientific results of the
combined cruises to the broader marine
science community of southern Africa.
The abstracts of talks and posters pre-
sented at SAMSS were subsequently
extended to include earlier cruise data,
and these were collated in a compen-
dium,12 which was distributed at the
annual BENEFIT Forum held in Swakop-
mund, Namibia, during 3–7 April 2000.
The compendium12 in effect served as
the precursor to the more expanded
articles contained in this issue. Contribu-
tions include research results from win-
ter observations on the hydrography,13
nutrient regeneration,14 distribution pat-
terns of ichthyoplankton in the Angola-
Benguela Front region;15 currents and hy-
drology of the southern16 and northern17
Benguela and off southern Angola18 and
large-scale surface flow patterns in the
Benguela Current;19 pigment bio-optical
properties20,21 and vertical and horizontal
variability22 of phytopankton in the
southern Benguela; secondary production
in the Benguela and Angola currents;23
and the stock identity of small pelagic
fish in the Orange River region.24
The shipboard research training pro-
gramme for the SADC region is a signifi-
cant milestone for BENEFIT. This single
programme was a hallmark in that it was
identified, planned and conducted by the
southern African marine science commu-
nity (represented by BENEFIT) using
predominately African resources. The
programme encompassed over 100 days
of sea-time, covered over 10 000 km longi-
tudinally, and provided training for 59
individuals from nine African nations
aboard three regional research vessels,
plus the German RV Poseidon. By any
standards, the programme was a substan-
tial success.
BENEFIT is indebted to all those persons who had the
vision to promote the regional partnership; the re-
spective ministries of Angola, Namibia and South
Africa, who have been unswerving in their support
to BENEFIT; and especially the original donors,
Germany and Norway, who believed in the regional
vision. The African Development Bank in particular is
singled out for its contribution to BENEFIT that
served as the primary funding base for conducting
the programme.
1. Parrish R.H., Bakun A., Husby D.M. and Nelson
C.S. (1983). Comparative climatology of selected
environmental processes in relation to eastern
boundary current pelagic fish production. In Pro-
ceedings of the Expert Consultation to Examine
Changes in Abundance and Species Composition of
Neritic Fish Resources, San José, Costa Rica, April
1983, (eds) G.D. Sharp and J. Giske. F.A.O. Fish.
Rep. 291(3), 731–777.
2. Bakun A. 1990. Global climate change and intensi-
fication of coastal ocean upwelling. Science 247,
198–201.
3. Hutchings L. (1992). Fish harvesting in a variable,
productive environment Searching for rules or
searching for exceptions? In Benguela Trophic Func-
tioning, eds A.I.L. Payne, K.H. Brink, K.H., Mann
and R. Hilborn. S. Afr. J. mar. Sci. 12, 297–318.
4. BENEFIT Science Plan (1997). BENEFIT Secretariat,
Windhoek, Namibia.
5. Payne A.I.L. and Lutjeharms J.R.E. (eds) (1997). A
Century of Marine Science in South Africa. Trans. Roy.
Soc. S. Afr. 52(1).
6. Payne A.I.L., Gulland J.A. and Brink K.H. (eds)
(1987). The Benguela and Comparable Ecosystems.
S. Afr. J. mar. Sci. 5.
7. Payne A.I.L., Brink K.H., Mann K.H. and Hilborn
R. (eds) (1992). Benguela Trophic Functioning. S. Afr.
J. mar. Sci. 12.
8. Pillar S.C., Moloney C.L., Payne A.I.L. and
Shillington F.A. (eds) (1998). Benguela Dynamics:
Impacts of Variability on Shelf-Sea Environments and
their Living Resources. S. Afr. J. mar. Sci. 19.
9. Siegfried W.R. and Field J.G. (1981). A description
of the Benguela Ecology Programme 1982–1986.
Rep. S. Afr. natn. scient. Progms 54. FRD, Pretoria.
10. Field J.G. (1996). The Benguela Ecology Pro-
gramme. In Proceedings of the International Seminar
on The Benguela Current and Comparable Eastern
Boundary Upwelling Ecosystems, Swakopmund,
Namibia, May/June 1995, ed. M.J. O’Toole, pp.
27–35. Gesellschaft für Technische Zusammen-
arbeit, Eschborn.
11. BENEFIT Training Plan (2000). BENEFIT Secretar-
iat, Windhoek, Namibia.
198 South African Journal of Science 97, May/June 2001 BENEFIT Marine Science
Fig. 5. Track chart and station positions of RV
Welwitchia during Leg 3 (Walvis Bay–Luanda– Walvis
Bay) of Cruise 3 in July/August 1999.
Fig. 6. Track chart and station positions of FRS Algoa
during Leg 4 (Walvis Bay–Cape Town) of cruise 3 in
July/August 1999.
Continued on p. 222
    
      
     
   
    
  
  
       

          
 
 
   
        
 
   
       
 
  

      
         
        
     
12. Verheye H.M. (ed.) (2000). BENEFIT Shipboard
Research Training Programme for the SADC
Region, 1999: Compendium of extended abstracts
presented at the ‘SAMSS 2000’ symposium, The
Wilderness, South Africa, 22–26 November 1999.
BENEFIT Secretariat, Swakopmund.
13. Mohrholz V., Schmidt M. and Lutjeharms J.R.E.
(2001). The hydrography and dynamics of the
Angola-Benguela Frontal Zone and environment
in April 1999. S. Afr. J. Sci. 97, 199–208.
14. Dittmar T. and Birkicht M. (2001). Regeneration of
nutrients in the northern Benguela upwelling
and the Angola-Benguela Front areas. S. Afr. J. Sci.
97, 239–246.
15. Ekau W., Hendricks A., Kadler S., Koch V. and
Loick N. (2001). Winter ichthyoplankton in the
northern Benguela upwelling and Angola-
Benguela Front regions. S. Afr. J. Sci. 97, 259–265.
16. Iita A., Boyd A.J. and Bartholomae C.H. (2001). A
snapshot of the circulation and hydrology of the
southern and central shelf regions of the Benguela
Current in winter 1999. S. Afr. J. Sci. 97, 213–217.
17. Mouton D.P., Boyd A.J. and Bartholomae C.H.
(2001). Near-surface currents and hydrology off
northern Namibia in July 1999. S. Afr. J. Sci. 97,
209–212.
18. Boyd A.J., Filipe V.L.L. and Bartholomae C.H. (2001).
Near-surface currents and hydrology off southern
Angola in July 1999. S. Afr. J. Sci. 97, 219–222.
19. Largier J. and Boyd A.J. (2001). Drifter observa-
tions of surface water transport in the Benguela
Current during winter 1999. S. Afr. J. Sci. 97,
223–229.
20. Barlow R.G., Aiken J., Sessions H.E., Lavender S.
and Mantel J. (2001). Phytoplankton pigment, ab-
sorption and ocean colour characteristics in the
southern Benguela ecosystem. S. Afr. J. Sci. 97,
230–238.
21. Bernard S., Probyn T.A. and Barlow R.G. (in
press). Measured and modelled optical properties
of particulate matter in the southern Benguela.
S. Afr. J. Sci. 97.
22. Mitchell-Innes B.A., Silulwane N.F. and Lucas M.I.
(2001). Variability of chlorophyll profiles on the
west coast of southern Africa in June/July 1999. S.
Afr. J. Sci. 97, 246–250.
23. Richardson A.J., Verheye H.M., Herbert V., Rogers
C. and Arendse L.M. (2001). Egg production,
somatic growth and productivity of copepods in
the Benguela Current system and the Angola-
Benguela Front. S. Afr. J. Sci. 97, 251–257.
24. Kanandjembo A., D’Almeida G. and Iita A. (2001).
The distribution of pelagic fish in the Orange
River region, July 1999: a separate marginal stock?
S. Afr. J. Sci. 97, 266–270.
BENEFIT: Introduction — Continued from p. 196


BENEFIT marine science in the Benguela Current region during 1999: introduction

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