Page 76 - Atlas Sea Birds Ver1

2.2.3.4 Coastal breeding sites of seabirds between Swakopmund and
Walvis Bay

Authors: DB Tom, RJ Braby, J Braby, and RJM Crawford

Abstract:
Ten species of seabird have nested at 10 localities between Swakopmund and Walvis Bay: Great White Pelican (Pelecanus
onocrotalus), Cape Cormorant (Phalacrocorax capensis), White-breasted Cormorant (P. lucidus), Crowned Cormorant (Microcarbo
coronatus), Kelp Gull (Larus dominicanus), Hartlaub’s Gull (Chroicocephalus hartlaubii), Grey-headed Gull (C. cirrocephalus), Greater
Crested Tern (Thalasseus bergii), Caspian Tern (Hydroprogne caspia) and Damara Tern (Sternula balaenarum). Bank Cormorant
(P. neglectus) may have attempted to breed. Bird Rock Platform was constructed to collect seabird guano and supports the northern-
most colony of Crowned Cormorant, a species endemic to the Benguela upwelling ecosystem, and Namibia’s only marine colony of Great
White Pelicans. It has held substantial numbers of Cape and White-breasted cormorants. The region has the largest colony of Damara
Terns, 147 pairs at Caution Reef, and altogether supports 175 pairs, or c. 22.5% of the overall population of this species.
Introduction:
Breeding by seabirds has been confirmed for ten localities between Swakopmund and Walvis Bay. Ten seabird species have nested in
this region and an eleventh may have attempted to at an eleventh site. The seabirds include all nine species that bred, or attempted
to breed, at Mile 4 Saltworks just north of Swakopmund: Cape Cormorant (Phalacrocorax capensis), Bank Cormorant (P. neglectus),
White-breasted Cormorant (P. lucidus), Kelp Gull (Larus dominicanus), Hartlaub’s Gull (Chroicocephalus hartlaubii), Grey-headed Gull
(C. cirrocephalus), Greater Crested (Swift) Tern (Thalasseus bergii), Caspian Tern (Hydroprogne caspia) and Damara Tern (Sternula
balaenarum). Additionally, Great White Pelican (Pelecanus onocrotalus) and Crowned Cormorant (Microcarbo coronatus) have nested
at Bird Rock Platform, which is the only extant coastal breeding locality of Great White Pelicans between Ilha dos Tigres in Angola and
Dassen Island off west South Africa and the northernmost breeding locality for Crowned Cormorant (Crawford et al. 1982b). Until 1947
and from 2000–2004 Great White Pelicans nested on sandy islands in Sandwich Harbour c. 55 km south of Walvis Bay (Berry and Berry
1975, Simmons 2015b) and in three years between 2001 and 2012 < 10 pairs bred at Vondeling or Jutten islands to the north of Dassen
Island in South Africa (Department of Forestry, Fisheries and the Environment, South Africa, unpublished data). Great White Pelican might
have nested on the guano platforms at Mile 4 Saltworks had it not been dissuaded from doing so by the platforms’ owners (Simmons et
al. 1998).
The positions of the ten breeding localities and the potential eleventh site are shown on Figure 1. Records of breeding are collated
below with brief descriptions of localities, first for species other than Damara Tern and then for Damara Tern. In both instances the localities
are ordered from north to south. ‘√’ signifies breeding occurred but the numbers were not ascertained; ‘?’ that breeding may have taken
place.
Two Globally Important Bird Areas (IBAs) were recognised for the region: the 30-km beach that links Swakopmund and Walvis Bay
and the town of Walvis Bay (Simmons et al. 1998). The 30-km beach is a strip of sand c. 0.7 km wide along the east Atlantic Ocean that
is interspersed with rocky outcrops and bounded on its eastern side by the main road linking Swakopmund and Walvis Bay. Two
resorts occur along this otherwise uninhabited section of coast, Langstrand and Dolphin Strand. The beach supports the densest known
breeding colony of Damara Terns at Caution Reef and in terms of shorebird density has the richest shoreline anywhere in southern Africa
(Simmons et al. 1998).
Walvis Bay is located in the Kuiseb River Delta. Wetlands south and west of the town comprise natural areas of Walvis Bay Lagoon
and include inter-tidal mudflats. A 10-km sandspit, Pelican Point, runs from south to north along the west of the lagoon and shelters the
bay from Atlantic swells. A saltworks built at the southern end of the lagoon was included in the IBA (Simmons et al. 1998). In terms
of numbers of birds (annual use by up to 150,000 birds), Walvis Bay is the most important coastal wetland in southern Africa and probably
one of the three most important coastal wetlands in Africa. It is especially important for waders migrating from the Palearctic and flamingos
(Simmons et al.1998).
1. Species other than Damara Tern Grey-headed Gull
Year No. of pairs
Swakopmund Sewage Works
Coordinates: 22.67 S; 14.55 E 1982 a 1
Description: The sewage treatment plant is located
northeast of Swakopmund town. a Brooke et al. (1999)
Conservation status: Not protected.
Species and numbers breeding: Swakop River mouth
Coordinates: 22.67 S; 14.52 E
Hartlaub’s Gull Description: Concrete supports of the former railway
bridge over the Swakop River just south of Swakopmund,
Year No. of pairs which may be surrounded by water after flow of the river
1978 a 5 (Williams 1987). In mid-September 1986, several Bank
Cormorants were seen on the supports. Two in full nuptial
1982 a c. 150 plumage were standing together, manipulating nesting
1983 a √ material, giving pair displays and mutually defending the
site. When the site was visited again in mid-October 1986,
1984 a c. 160 no cormorants were on the supports and it is unknown
a Williams et al. (1990) whether egg-laying occurred (Williams 1987).

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