Fisheries - Enviro Dynamics Namibia

F I S H E R I E S , M A M M A L S A N D S E A B I R D S S P E C I A L I S T S T U D Y
Utne-Palm et al. 2010) and the bearded goby has become an increasingly important food source
for predators (Crawford et al. 1987, Boyer and Hampton 2001a), there may have been a shift in
diet of some species (including horse mackerel) to focus on S. bibartus.
2.1.2 Sardine
Historically spawning of sardine Sardinops sagax took place at two locations roughly 60 km off
the Namibian coast: off Walvis Bay and further north at the meeting of the Benguela and Angola
Current systems (O’Toole 1977) (Figure 2). Spawning in the north was predominantly by young
adults and peaked in late summer / autumn around the 200 m isobath (Crawford et al. 1987). In
contrast, older fish spawned further south in summer, in cooler waters close to upwelling zones.
Following spawning, larvae drifted southward along the coast. Sardine would then migrate
northwards where juveniles and young adults would spawn for the first time. Adult fish would
subsequently return to south to spawn off Walvis Bay (Boyer and Hampton 2001a). Following the
collapse of the sardine stock in the
1970s, spawning in the south is
thought to have weakened
(Crawford et al. 1987) as the
migration of adult sardine has
contracted (Boyer and Hampton
2001a). While the diet of juvenile
sardine is focused primarily on
zooplankton, phytoplankton is also
utilised by adults in areas where it
is consistently available in high
abundance (James 1988).
2.1.3 Anchovy
The distribution and movement
patterns of anchovy Engraulis
encrasicolus in Namibian waters
are similar to those described for
sardine (Figure 3). The only
exceptions are that significant
spawning by anchovy takes place
only north of Walvis Bay (Shannon
and Pillar 1986) and larvae
occurred in high density further
than 100 km offshore (O’Toole
1977). Due to the very small size of
current stocks, the present
distribution and movement of
anchovy off Namibia is unclear, but
the life history of this species is
likely to have changed from that
previously recorded (Boyer and
Hampton 2001a).
Final Report
Namibian Marine Phosphate (Pty) Ltd.
Figure 3. Distribution of anchovy in the Benguela Region
Figure 1. Distribution of anchovy in the
BCLME region
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