Page 337 - Atlas Sea Birds Ver1

7 000
2 500
6 000
2 000
5 000
PAIRS 1 500 PAIRS 4 000

3 000
1 000
2 000
500
1 000
1963 1969 1975 1981 1987 1993 1999 2005 2011 2017 1975 1979 1973 1987 1991 1995 1999 2003 2007 2011 2015 2019

Figure 4. Numbers (pairs) of Great White Pelicans breeding at Figure 5. Maximum numbers of Great White Pelicans counted
Lake St Lucia, 1963–2021 annually at Lake St Lucia, 1963–2021
circumstances, such as low water levels or drought, the Reproductive Units) of a species classified as Vulnerable’
Great White Pelicans at Lake St Lucia sometimes nested (BirdLife International 2020). Then, if the southern African
at previously occupied sites, even though they had become population is considered VU, Ilha dos Tigres, Hardap Dam
accessible to terrestrial predators. Maxima of counts (Kolberg 2009, Simmons 2015), Dassen Island and Lake
of Great White Pelicans at Lake St Lucia also showed St Lucia would qualify as IBAs for southern Africa’s Great
substantial fluctuations (Figure 5). Whereas maxima from White Pelican population. Further observations should be
1976–1991 were all less than 2,000 individuals, that for made at Bird Rock Platform to ascertain numbers now
2012 was 7,240 birds. Maxima then reverted to < 2,000 breeding there.
birds from 2018–2021. Most recently Lake St Lucia held 70% and Dassen
Island 22% of southern Africa’s coastal population, which
Conservation status, Important Bird and Biodiversity means that factors affecting these colonies will have major
Areas, and threats implications for the population. Fluctuating water levels that
flood nests or allow access to breeding sites by terrestrial
In 2015, the Great White Pelican was classified as predators and altered availability of food were considered
Vulnerable (VU) in both Namibia (Simmons 2015) and the biggest threats to the colony at Lake St Lucia (Bowker
South Africa (Bowker 2015). In 2000, the number of Great 2015). Fluctuating water levels and climate may influence
White Pelicans nesting in South Africa was gauged to be availability of food to pelicans (Guillet and Crowe 1968,
c. 3,500 pairs (Crawford and Taylor 2000). In 2007, the Bowker and Downs 2008c). Human disturbance at
number of this species breeding coastally around Angola, breeding colonies (Berry et al. 1973), ingestion of plastics,
Namibia, and South Africa was thought to be 3,702 pairs and disease (Crawford et al. 1995) are other threats to the
(Kemper et al. 2007). The sum of the maximum counts at species.
each coastal breeding locality made in the five-year period
2018–2022 was 1,556 pairs (Table 1). The sum of the most
recent counts made at each coastal locality was 1,480 pairs
(Table 1). These values suggest that the coastal population
of Great White Pelicans in southern Africa decreased by
58–60% between 2007 and 2020. Numbers of pelicans
breeding at Bird Rock Platform, Dassen Island and Lake St
Lucia and numbers observed at Lake St Lucia all appear
to have decreased over the past 10–15 years (Figures
2–4), confirming the downward trends observed by Bowker
(2015) and Simmons (2015). Therefore, in the absence of
recent data regarding sporadic breeding at inland sites,
there is no reason to change the VU classifications of the
species in Namibia and South Africa.
Important Bird and Biodiversity Areas (IBAs) are
identified through the use of specific criteria. Criterion
A1 is that ‘the site is known or thought regularly to hold
significant numbers of a Globally Threatened species’
(BirdLife International 2020). Guidelines for the application
of IBA criteria recommend that to meet A1 ‘a site must Male and female White Pelicans at Dassen Island (photo M van
support: at least 30 individuals (the equivalent of 10 Pairs/ Onselen)

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