Page 82 - Atlas Sea Birds Ver1

2.2.3.5 Breeding sites of seabirds along the coast of Namib Naukluft
National Park

Authors: DB Tom, PA Bartlett, J Braby, RJM Crawford, J-A Delport, BM Dyer, AB Makhado, and R Jones

Abstract:
Eleven species of seabird have nested at 12 localities in the Namib Naukluft National Park: African Penguin (Spheniscus demersus),
Great White Pelican (Pelecanus onocrotalus), Cape Gannet (Morus capensis), Cape Cormorant (Phalacrocorax capensis), Bank Cormo-
rant (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 region in-
cludes two offshore islands. The northern of these, Hollamsbird Island, is the northernmost confirmed breeding locality for African Penguin,
Cape Gannet and Bank Cormorant but gannets no longer breed there and the status of penguins at the island is uncertain. Mercury Island,
farther south, is now the most northern breeding locality of Cape Gannet. In 2010, it held 72% of the global population of Bank Cormorant
and 73% of Namibia’s African Penguins. Great White Pelican bred at sand islands in Sandwich Harbour until 1947 and again in the early
2000s but breeding ceased when the islands disappeared.
Introduction:
Breeding by seabirds has been confirmed for 12 localities along the generally arid coast of the Namib Naukluft National Park (NNNP),
which extends from the south of the Kuiseb River delta to the north of Hottentots Bay. The localities include Hollamsbird and Mercury
islands and ten mainland sites. Eleven seabird species have nested in this region, including nine of the 11 that bred or may have bred
between Walvis Bay and Swakopmund: Great White Pelican (Pelecanus onocrotalus), Cape Cormorant (Phalacrocorax capensis), Bank
Cormorant (P. neglectus), White-breasted Cormorant (P. lucidus), Crowned Cormorant (Microcarbo coronatus), Kelp Gull (Larus dominica-
nus), Hartlaub’s Gull (Chroicocephalus hartlaubii), Caspian Tern (Hydroprogne caspia) and Damara Tern (Sternula balaenarum). Absent
from the list of species that bred between Swakopmund and Walvis Bay are Grey-headed Gull (C. cirrocephalus) and Greater Crested
(Swift) Tern (Thalasseus bergii). Additions to that list are African Penguin (Spheniscus demersus) and Cape Gannet (Morus capensis), for
both of which the northernmost breeding locality was Hollamsbird Island (Crawford et al. 1983, Shelton et al. 1984). Hollamsbird Island is
also the northernmost confirmed breeding locality for Bank Cormorant (Cooper 1981). Within NNNP and its adjacent islands Great White
Pelican and Caspian Tern have only been recorded nesting at Sandwich Harbour, the most northern of the region’s seabird breeding locali-
ties and the only one having a permanent supply of fresh water.

The positions of the 12 breeding localities are shown on guela Current upwelling ecosystem: African Penguin, Cape
Figure 1. Records of breeding are collated below with brief Gannet, and Cape, Bank and Crowned cormorants (Sim-
descriptions of localities, first for the two islands and then mons et al. 1998). In 2010, Mercury Island held 72% of the
for the mainland sites. In both instances the localities are global population of Bank Cormorants (Roux and Kemper
ordered from north to south. ‘√’ signifies breeding occurred 2015) and 73% of Namibia’s African Penguins (Crawford et
but the numbers were not ascertained; ‘?’ that breeding al. 2013). A heat wave apparently caused major mortality
may have taken place. In addition to the 12 known breed- of Bank Cormorant chicks there in 2005, suggesting the
ing localities, Braby (2011) estimated that 20 single pairs species may be susceptible to global warming (Sherley et
of Damara Terns nested in NNNP in 2010. A short summary al. 2012).
of methods used to obtain counts is given in the chapter
‘Introduction to Seabird Breeding Localities’. 1. Islands
The NNNP was recognised as a Globally Important Bird
Area (Simmons et al. 1998). It incorporates a large portion Hollamsbird Island
of the Namib Desert. Extensive sand dunes, which form
a dune sea, run parallel to the coastline for up to 120 km
inland. The Naukluft Mountains are part of a high-rising es- Coordinates: 24.63 S; 14.53 E
carpment that forms the western edge of Namibia’s interior Description: Northernmost of Namibia’s main offshore
highlands (Simmons et al. 1998). The coastal area of the islands, it has a surface area of c.1 ha and a precipitous lee-
NNNP is mostly inaccessible to humans. Concessions are ward side. Situated about 10 km offshore it has since 1963
given to some tour operators to take visitors to selected been mainly a rookery for Cape Fur Seals (Arctocephalus
sites (Braby 2011). Within NNNP, Sandwich Harbour was pusillus pusillus) with most seabirds subsequently nesting
recognised as a Globally Important Bird Area, as was ad- on top of buildings or on a jetty (Rand 1963).
jacent Mercury Island (Simmons et al. 1998). Seabird guano was collected in 18 years between
Sandwich Harbour is one of the most important wet- 1896 and 1954, the total quantity removed from the island
land areas in southern Africa, regularly supporting over in this period being 1,491 metric tons (Tom et al. 2024).
Conservation status: It falls within the Namibian Islands’
50,000 birds in summer and over 20,000 in winter. Within Marine Protected Area (NIMPA) and has restricted access
Sandwich Harbour, the northern wetlands have the high- (Currie et al. 2009, Ludynia et al. 2012).
est diversity of birds (up to 51 species), while the southern
mudfalts hold the largest number of birds, dominated by
terns, sandpipers, flamingos and cormorants (Simmons et Note: Cape Gannets bred at Hollamsbird Island in 1786
when it was known as Booby Island (Kinahan 1990), and
al. 1998). from at least 1828 until at least 1938. They did not breed
Mercury Island, is an important breeding locality for sea- there in 1956 or subsequently (Crawford et al. 1983,
birds, including five species that are endemic to the Ben- Shaughnessy 1984).

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