Page 566 - Atlas Sea Birds Ver1

3.17 Numbers, trends, status, movement and conservation of
Damara Tern (Sternula balaenarum) in South Arica

Authors: AP Martin, PA Whittington, BM Dyer, RJM Crawford, and AB Makhado

Abstract:
Damara Terns (Sternula balaenarum) are a breeding endemic to the Benguela upwelling ecosystem, where they breed between south
Angola and southern South Africa, mostly in Namibia. In the late 1970s c.150 pairs of Damara Terns bred in South Africa, reducing to
an estimated minimum of 65 pairs in 2010. Following losses in the west and despite increases in the east, this decreased over the next
10 years by c. 20% to 52 pairs in 2018–2021. Then the South African population was confined to three isolated pockets of c. 5 pairs,
c. 4 pairs and c. 43 pairs in the Northern, Western and Eastern Cape Provinces, respectively, and breeding had ceased at six of the
species’ 14 South African colonies. Although Damara Terns were first recorded breeding in the Eastern Cape in 1980, that province held
83% of South Africa’s population in 2018–2021 when there were < 200 mature individuals in South Africa. The South African Damara Tern
population satisfied IUCN criteria for Regionally Endangered. A main cause of the decrease in west South Africa was disturbance at and
displacement from breeding sites. Some colonies in the Eastern Cape are facing similar threats and urgently require protection. Almost
all Damara Terns were previously thought to migrate to coastal waters off West Africa during their non-breeding season. However, more
recently, it is likely that most Damara Terns from the Eastern Cape overwintered in Mozambique. One chick banded in the Eastern Cape
in January 2022, was photographed at the San Sebastian Peninsula near Vilanculos in Mozambique in June 2022 and seen back in the
Eastern Cape in October 2022.

Introduction:
The Damara Tern (Sternula balaenarum) is one of seven seabird species that are breeding endemics to the Benguela ecosystem off
southwest Africa, where it breeds around the coast from south Angola to South Africa’s Eastern Cape Province (Hockey et al. 2005).
It has bred at one site in Angola (Simmons 2010), 57 in Namibia (Braby 2011), and 14 in South Africa (Randall and McLachlan 1982, Martin
1991, 2019, Tree 2000, Martin and Taylor 2002, Braby 2011, Department of Forestry, Fisheries and the Environment (DFFE) unpubl.). All
breeding sites, except Possession Island in Namibia, are on the mainland. The locations of the South African breeding sites are shown
in Figure 1. This chapter collates information on numbers breeding at these sites in order to gauge the present level of, and trends in, the
abundance of Damara Terns. It assesses the Red List status of, identifies Important Bird and Biodiversity Areas (IBAs) for, and considers
threats to Damara Terns in South Africa and documents movements to a new over-wintering area.

Numbers
Numbers of Damara Terns estimated to have bred at
South African sites from 1980–2021 are shown in Table 1.
Information was collated from various sources: the count
for Brandfontein in 1995 was by PA Whittington and G
Nunn (unpubl.). Other information for the seven colonies
located west of Cape Agulhas and for De Hoop Nature
Reserve up until 2010 was from Braby (2011), who for
the 20 pairs shown for Dreyers Pan for 1990 gave the
date as the ‘1990s’ and for the c. 2 pairs shown for De
Hoop for 1990 gave no date. Information for these seven
sites for 2011–2017 was from Crawford et al. (2018) and
thereafter from DFFE (unpubl.). Counts for Struis Bay for
1992–1996 and 2010–2018 were from DFFE (unpubl.)
and for 1997–2002 from Williams et al. (2004). For A Damara Tern at its nest (photo BM Dyer)
Cape Recife, the sources were: 1999 (Tree 2000), 2001
(Martin and Taylor 2002), 2003 (Crawford et al. 2009), range, was used. Braby (2011) thought that 29–82 pairs
2009 (Whittington et al. 2015), 2018 (Martin 2019). For of Damara Terns bred in the Northern Cape in the 1990s
Old Abalone Farm they were: 1983 (Watson and Randall and 2000s, but the estimate in 2018 was just five pairs
1995), 1990 (Martin 1991), 1999, 2008, 2011–2019 (Martin (Table 2). By 2017, breeding in that province had ceased
2019), 2007 and 2009 (Whittington et al. 2015), and 2020– at Alexander Bay diggings and Port Nolloth Pan because
2021 (AP Martin unpubl.). For Dunes east of Coega and of mining and human disturbance (Figure 2), and at Karas
Schelmhoek Dunefields they were: Martin (2019, unpubl.). Pan where seepage of water from an adjacent diamond
For Alexandria Dunefields they were: 1980 (Randall and mine resulted in a large portion of the pan having a muddy
McLachlan 1982), 1991–1994 (Watson 1995), 2005, 2008, substrate (Crawford et al. 2018).
2016–2019 (Martin 2019), 2008, 2009 (Whittington et al. Damara Terns have bred at three sites in the Western
2015), and 2020–2021 (AP Martin unpubl.). Cape, where Braby (2011) thought 15–35 pairs nested in
Estimates of the minimum and maximum numbers of 2010. However, breeding was not recorded at Brandfontein
pairs at sites in 2010 (Braby 2011) and of numbers breeding or De Hoop Nature Reserve in the late 2010s and the
in 2018–2021 are shown in Table 2. In the latter instance estimate for Struis Bay was four pairs in 2018, down from
the most recent count, or the mid-point of the most recent 11 pairs in 2002 (Williams et al. 2004). From 1977–2002,

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