Page 123 - Atlas Sea Birds Ver1

2.2.4.1 Coastal breeding sites of seabirds in South Africa’s Northern
Cape Province

Authors: BM Dyer, L Geldenhuys, RJM Crawford, and AB Makhado

Abstract:
Eight seabird species have bred at 31 localities along the coast of South Africa’s Northern Cape Province: Cape Cormorant (Phalacroco-
rax capensis), Bank Cormorant (P. neglectus), White-breasted Cormorant (P. lucidus), Crowned Cormorant (Microcarbo coronatus), Kelp
Gull (Larus dominicanus), Hartlaub’s Gull (Chroicocephalus hartlaubii), Caspian Tern (Hydroprogne caspia) and Damara Tern (Sternula
balaenarum). Numbers of all eight species decreased since initial estimates of their abundance in the province were made in the latter
part of the 20th century. Likely drivers of the decreases were reduced availability of food and the loss of suitable breeding habitat, includ-
ing in the Orange River Mouth and at some coastal pans and islands, which have resulted from a variety of human uses, alterations and
disturbances.

Introduction:
Eight seabird species have bred along the coastline of South Africa’s Northern Cape Province. The Orange River in the north forms
its border with Namibia, whereas its southern boundary with the Western Cape Province lies about 7 km south of the dry Brak River
(Figure 1). The species that have bred are Cape Cormorant (Phalacrocorax capensis), Bank Cormorant (P. neglectus), White-breasted
Cormorant (P. lucidus), Crowned Cormorant (Microcarbo coronatus), Kelp Gull (Larus dominicanus), Hartlaub’s Gull (Chroicocephalus
hartlaubii), Caspian Tern (Hydroprogne caspia) and Damara Tern (Sternula balaenarum).
The breeding has taken place at 31 localities, which are shown in Figure 1 and briefly described below. For each locality, records of
breeding by the different species were collated for all years having information. When multiple counts were obtained for a species in a
given year, the maximum was shown on the relevant table. ‘√’ signifies that breeding occurred at a locality but the numbers were not as-
certained; ‘?’ that breeding may have taken place. A short summary of methods used to obtain the estimates of numbers breeding is given
in the chapter ‘Introduction to Seabird Breeding Localities’.
The Orange River Mouth (ORM) Wetlands, on South Africa’s border with Namibia, were considered to be a globally Important Bird and
Biodiversity Area (IBA, Barnes and Anderson 1998, Simmons et al. 1998, Marnewick et al. 2015). It was the sixth most important coastal
wetland in southern Africa in terms of the overall numbers of wetland birds that it supported, which were as high as 26,000 individuals
comprising 56 species. Waterbirds used the ORM primarily as a breeding area or as a stopover on migration (Barnes and Anderson 1998).
However, numbers of seabirds that bred in the Northern Cape decreased in the 21st century. Likely drivers of the decreases included
reduced availability of food for seabirds that compete with fisheries for prey (e.g. Crawford et al. 2008, 2015, 2019, 2022) and the loss of
suitable breeding habitat, including in the ORM and at coastal pans and islands, which have resulted from a variety of human uses, altera-
tions and disturbances (Crawford et al. 2018).
Sources of information for species and numbers breeding: The estimates of numbers of seabirds breeding at the 31 localities
were from Crawford et al. (2018) updated by unpublished records of the Northern Cape Department of Agriculture, Environmental Affairs,
Rural Development and Land Reform and South Africa’s Department of Forestry, Fisheries and the Environment (DFFE). The information
in Crawford et al. (2018) was largely based on the following sources: Cape Cormorant (Cooper et al. 1982, Crawford et al. 2007a, 2016);
Bank Cormorant (Cooper 1981, Crawford et al. 1999, 2008, 2015, Crawford 2007); White-breasted Cormorant (Brooke et al. 1982, Craw-
ford 2007, Crawford et al. 2013); Crowned Cormorant (Crawford et al. 1982b, 2012, Crawford 2007); Kelp Gull (Crawford et al. 1982a,
2009, Whittington et al. 2016); Hartlaub’s Gull (Williams et al. 1990, Crawford et al. 2007b); Caspian Tern (Cooper et al. 1992); and
Damara Tern (Braby 2011).

Above a view of the Orange River mouth (photo BM Dyer)

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