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The regional population of Great White Pelican Pelecanus onocrotalus has been quantified at c. 2 500 pairs, restricted to less than 5 breeding locations, and is vulnerable to short-term human activities and stochastic events. For these reasons, the species is assessed as regionally Vulnerable.
The Great White Pelican is widely distributed in Africa and parts of Eurasia (Crawford 2005). The species is nomadic, moving vast distances in response to environmental conditions. In South Africa, breeding takes place at three localities, namely Vondeling and Dassen islands in Western Cape, and at Lake St Lucia in KwaZulu-Natal. All three sites are IBAs. Birds spread out from these breeding sites, extending up the West Coast of Western Cape, and in KwaZulu-Natal southward down the East Coast to Durban and northward into Mozambique. Non-breeding birds are found scattered at larger waterbodies in all other provinces (Williams and Borello 1997). The species is a vagrant to Swaziland (Parker 1994). It is not known whether movement between the populations in Western Cape and KwaZulu-Natal occurs; consequently, these have been treated as sub-populations.
The global population is estimated at 75 000 pairs, of which 80% breed in Africa (BirdLife International 2014). The regional population is estimated at c. 2 500 pairs or 5 000 mature individuals, of which c. 2 000 pairs occur in KwaZulu-Natal and the remaining c. 500 pairs in Western Cape (Crawford et al. 2012). Confidence in this regional population estimate is high.
The overall global population trend is uncertain, as some populations are decreasing while others are increasing or stable (Dodman and Diagana 2006). Regular counts at Lake St Lucia since 2004 indicate that numbers can fluctuate from zero to greater than 8 000 adults (MB Bowker pers. obs). Crawford and Taylor (2000) estimated that the colony at Lake St Lucia was in the region of 3 000 pairs, which has decreased to c. 2 000 pairs (Crawford et al. 2012). There is concern over the number of unsuccessful breeding attempts that have taken place over the past decade and the medium and long-term impacts that this may have on the structure of this sub-population. The Western Cape sub-population increased fourfold from a maximum count of 320 pairs in 1978 to 834 pairs in 2004 (Crawford et al. 2012), before decreasing slightly to less than 370 pairs in 2006. The population trend for the Western Cape sub-population is stable, but could be dramatically reversed with a change in farming practices. The overall regional population trend is downward. Confidence in this estimate is high.
Fluctuating levels and salinity of Lake St Lucia, which impact on food productivity and availability of nest sites, are the biggest threats facing the KwaZulu-Natal sub-population (Bowker and Downs 2008a). Low influx of water from the catchments into the lake has resulted in low water levels and a resultant failure by the birds to initiate breeding (Bowker and Downs 2008b). In Western Cape, the breeding sites are more secure, but feeding on offal at farms is a major concern. There is potential for extreme fluctuations in food supply associated with this, and for introduction of avian pathogens (Crawford et al. 1995) that could have devastating consequences (de Ponte Machado 2007). It is uncertain how this change in foraging behaviour will affect the population or whether this food resource will remain available. Lesser threats include human disturbance at breeding colonies (Berry et al. 1973), pollution, particularly the ingestion of plastics (Crawford et al. 1995), collision with power-lines, as well as starvation and breeding failure during droughts.
All breeding sites in the region have some form of protection. iSimangaliso Wetland Park (SA058) is a provincial nature reserve, Ramsar Site and World Heritage Site, while both Dassen and Vondeling islands are provincial nature reserves. Conservation measures include regular monitoring of population numbers and their breeding effort.
Conservation action in Western Cape needs to focus on the interaction between this species and the region's pig and chicken farmers, and the development of management plans. In KwaZulu-Natal, water abstraction from Lake St Lucia's catchments needs to be monitored and controlled. It is essential that measures are adopted that will ensure the retention of breeding islands in this system. Food sources available to pelicans also need to be monitored.
* Possible movement between the KwaZulu-Natal and Western Cape sub-populations needs to be investigated.
* The state of Lake St Lucia, and the impact that it is having on breeding success of the KwaZulu-Natal sub-population, need to be investigated.