Page 568 - Atlas Sea Birds Ver1

There may be movement of birds between colonies in
Algoa Bay both within and between years (Martin 2019).
A chick ringed at Cape Recife in December 2001 was
found breeding at the Alexandria Dunefields in February
2010, when aged c. 9 years (Whittington et al. 2015). Braby
(2011) thought that 21–31 pairs of Damara Terns nested
in the Eastern Cape in 2010, which increased to c. 43 pairs
in 2018–2021 (Table 2).
In Algoa Bay, Eastern Cape, a maximum of 113 adult
Damara Terns was counted at Schelmhoek on 4 January
2019 and there were 56 adults at other active colonies in
Algoa Bay during the period late December 2018 to early
January 2019, giving a potential maximum of 169 mature
individuals. On 6 February 2019 there were 126 birds,
including a minimum of 11 juveniles, along the Alexandria
coastline (AP Martin unpubl.). With just 9–10 pairs of
Damara Terns breeding elsewhere in South Africa, there
are unlikely to be more than 200 mature individuals in
South Africa.

Population trend and conservation status

In the late 1970s c. 150 pairs of Damara Terns bred in South
Africa (Cooper et al. 1984). Underhill (2000) estimated
c. 100 pairs and Braby (2011) estimated 65–146 pairs, of
which the majority (44–115 pairs) were in the Northern and
Western Cape (Table 2). Crawford et al. (2012) estimated
just 36 pairs breeding in South Africa. In 2018–2021 there
were an estimated 52 pairs breeding in South Africa with all
but 9 pairs from the Eastern Cape (Table 2).
Figure 2. Photographs (BM Dyer) taken in 2011 of Port Nolloth
Pan showing the derelict Damara Tern sign prohibiting vehicular Modal age at first breeding of Damara Terns is four
access (top) and the use of the pan’s perimeter as a waste dump years and survival of adults is 0.88 per annum (Braby
(bottom) 2011). Based on these parameters generation length (G)
for the species was calculated to be 12.33 years, so that
the Struis Bay colony nested at the east of Struis Bay 3G = 37 years (Braby et al. 2024). The observed decrease
beach near the Heuningnes River Estuary (c. 34.717° S, of 65% in breeding pairs from c. 150 to c. 52 over
20.105° E, Williams et al. 2004) but by 2018 it had shifted 40 years (1980–2020) equated to a decrease of c. 60%
west and birds bred near and in the car park at Struis Bay in 3G. The 20% decrease from c. 65 pairs in 2010 to
beach (34.774° S, 20.037° E, DFFE unpubl.). Following a c. 52 pairs in 2018–2021 equated to a decrease of 24.7%
ban after 2001 on use of off-road vehicles near the section in 1G.
of the beach then used by Damara Terns for nesting, all 11 The South African Damara Tern population satisfies
pairs that bred in 2002 successfully fledged chicks by the several of the criteria of the International Union for
end of December. Prior to the ban some chicks fledged Conservation of Nature (IUCN) for classification as
later. It was thought that the extra time, provided by early regionally Endangered (IUCN 2012).
fledging, for immature birds to prepare for their northward
migration to winter in West Africa may benefit their survival • Population reduction Criterion A2: A population
(Williams et al. 2004). reduction ≥ 50% in 3G observed, estimated, inferred,
Damara Terns were first recorded in the Eastern Cape or suspected in the past where the causes of reduction
at the Sundays River Mouth in January 1979, when a may not have ceased or may not be understood or
juvenile bird was seen being fed by two adults (Every 1979, may not be reversible.
Underhill et al. 1980). The record represented an eastward • Geographic range Criterion B2(a): Area of occupancy
extension of about 550 km in the known distribution of this < 500 km coupled with (a) severely fragmented & (b)
2
species (Crawford et al. 2009). Damara Terns were first continuing decline in (iii) area, extent and/or quality
observed breeding in the Eastern Cape in 1980, when of habitat, (iv) number of locations and (v) number of
14 pairs nested in the Alexandria Dunefields (Randall mature individuals.
and McLachlan 1982). They subsequently nested at four • Small and declining population Criterion C1: < 2,500
more sites in that province (Martin 1991, 2019, Tree 2000, mature individuals with a decline of at least 20% over
Martin and Taylor 2002) but stopped breeding at Cape 2 generations.
Recife before the mid-2000s (Table 1). In the Alexandria • Small and declining population Criterion C2: A
Dunefields, there was an eastward shift of 5–10 km in continuing decline and a(i) Number of mature
the locations of most nest sites between the early 1990s individuals in largest sub-population < 250.
and the late 2010s (Whittington et al. 2015) and by 2019 • Very small population Criterion D(1): < 250 mature
breeding extended up to 28 km east of the Sundays River. individuals.

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