Rationale
(Changed due to Not applicable)
The Lesser Flamingo Phoeniconaias minor is classified as globally Near Threatened due to a perceived decline in population numbers. In addition, a proposed large-scale soda ash extraction at Lake Natron in Tanzania, the most important breeding colony, although currently on hold, poses a serious threat to the species and would qualify the species for up-listing to a higher threat category. In southern Africa, an apparent decrease of c. 27% between the mid-1970s and 1994 indicates that the regional population trend mirrors that of the global population, approaching the threshold for Vulnerable under criterion A2. The species is assessed as regionally Near Threatened in line with its global status.
Distribution
The Lesser Flamingo occurs in sub-Saharan Africa, with high densities at the Great Rift Valley Lakes of East Africa and in southern Africa (Brown et al. 1982, Simmons 2000). There is a small coastal population in West Africa (Simmons 2000) and additional small populations on the Arabian Gulf Coast, India and Pakistan (Mundkur 1997). Until recently, the only regular breeding sites in Africa were Lake Natron, Tanzania, Etosha Pan, Namibia and Sua Pan, Botswana (Berry 1972, Hancock and Liversedge 1990, Simmons 1996, Simmons 1997, McCulloch and Irvine 2004). During four consecutive years, from 2007 to 2011, Lesser Flamingos bred on a purpose-built, S-shaped, 25x250 m island constructed at Kamfers Dam, just north of Kimberley (Northern Cape, South Africa) (Anderson 2008, Anderson and Anderson 2010). An estimated 24 000 chicks were produced during these breeding events, representing the only documented incident of successful breeding in South Africa. The island flooded in the summer of 2011/2012 and no breeding has subsequently taken place (Anderson and Anderson 2012). At least 12 breeding attempts at sites in South Africa have been unsuccessful (Uys and Macleod 1967, Brooke 1984), mainly because the sites are small, with low numbers of flamingos, and therefore unsuitable for mass breeding (Simmons 1996, Simmons 1997).
The Lesser Flamingo's non-breeding distribution in South Africa is centred on the central Highveld, but it also occurs along the West and South coasts (Borello et al. 1998). Large numbers have been recorded at Lake St Lucia, KwaZulu-Natal (IBA SA058), Berg River (IBA SA104), Wadrif Saltpan and Langebaan Lagoon (IBA SA105) in Western Cape, and Kamfers Dam, Northern Cape (IBA SA032) (Taylor 1999). It is a vagrant to Swaziland (Parker 1994) and a potential vagrant to Lesotho (Osborne and Tigar 1990). A satellite telemetry study of individuals from their breeding site at Sua Pan, Botswana identified their migration to non-breeding feeding grounds in South Africa and Mozambique, suggesting their reliance on a wide variety of small wetlands and coastal areas in the region during the non-breeding season (McCulloch et al. 2003). In excess of one million non-breeding Lesser Flamingos have been observed at Etosha Pan (Berry 1972) and Sua Pan (Parker 1975). The large influxes of birds in southern Africa coincide with decreases in East Africa, which suggests movements between these two populations (Simmons 1996).
Population
The global population has been estimated at 2-6 million individuals (Kahl 1975, Brown et al. 1982, Simmons 2000), with c. four million occurring in Africa (Simmons 1997). The most recent estimate calculates the population to number 865 000-2 640 000 individuals (mean 1 752 500) (Childress et al. 2008). The southern African population has previously been estimated at 55 000 (Cooper and Hockey 1981), 60 000 (Williams and Velásquez 1997b) and 40 000 (Simmons 1996, Simmons 1997d). It is possible that these were underestimates, largely due to the difficulty of counting large aggregations, their dispersion at remote wetlands across southern Africa, their frequent movements between feeding sites, and their use of isolated areas of the larger feeding and breeding sites. Large numbers of Lesser Flamingos have also recently been recorded breeding at Sua Pan, including 64 287, 90 690 and 44 731 pairs in 1999/2000, 2005/2006 and 2008/2009 respectively (McCulloch and Irvine 2004).
Population trend
The global population trend is decreasing owing to habitat degradation and disturbance, although some populations may be stable and others have unknown trends, thus a moderately rapid decline is suspected overall (Delany and Scott 2006). Simmons (1996, 1997) suggested that the southern African population had decreased from the early-1980s to the mid-1990s by about 15 000 birds or 27%. Simmons (1996) attributed this population decline to poor recruitment brought about by infrequent breeding at Etosha Pan and Sua Pan. It is unknown whether this suggested population trend has continued although consistent successful breeding events at Sua Pan between 2000 and 2012 may have resulted in an improved recruitment rate in recent times (McCulloch unpubl. data). Confidence in the regional trend estimate is medium.
Threats
The most critical threat to the survival of the Lesser Flamingo is degradation of its specialised breeding and feeding habitats through altered hydrology and water quality, wetland pollution, extraction of salt and soda ash, and the disruption of its few breeding colonies by human activities (Childress et al. 2008) In South Africa, the threats include disturbance by low-flying aircraft, collisions with fences and utility lines, fluctuating water levels, salt extraction, pollution of wetlands and human interference (Connor 1980, Hall 1983, Brooke 1984, Aves 1992, Simmons 1996, 1997, Hill et al. 2013) Flamingos may be attracted to wet roads and runways, which are perceived to be wetlands by overflying birds and it is therefore not certain whether the development of large solar farms in South Africa will affect Lesser Flamingos. A housing estate proposed for development on a property adjacent to Kamfers Dam was considered to be a potential threat to the dam's flamingos.
Avian predators such as eagles, vultures and Marabou Storks Leptoptilos crumeniferus take chicks and adults and constant harassment causes colony abandonment in East Africa. Disturbance by low-flying aircraft may result in colony desertion (RE Simmons and R Braby pers. obs.). Occasional mass die-offs take place in East Africa, possibly due to avian tuberculosis (Kock et al. 1999), but this has not been recorded in southern Africa (Simmons 2005). Avian pox virus has recently been documented in South Africa (Zimmermann et al. 2011), and its spread could be exacerbated by deteriorating water quality and proliferation of biting insects at wetlands frequented by Lesser Flamingos. Threats to breeding birds in Namibia and Botswana include soda ash and salt mining (Simmons 1996, Simmons 1997) resulting in a lowering of water table. At Sua Pan the main threats include disturbance of the breeding colony by low-flying aircraft, filming and tourism and the potential damming of the Nata and Mosetse rivers, while groundwater abstraction by mining in the surrounding watershed threatens the flood period of the pan around the breeding site (McCulloch, unpubl. data). Threats in Namibia include pesticide use, increasing human populations in northern catchments, and lowered water tables in eastern catchments reducing water inflow to Etosha Pan. Some breeding sites may be threatened by the damming of feeder rivers, particularly at Lake Natron in Kenya, and possibly also the Nata River into Sua Pan. Neither of these sites have national park status.
Conservation
Underway
There is varying protection of the feeding sites, from IBA status (Kamfers Dam), Ramsar status (Orange River Mouth) to formal protection (Lake St Lucia). Efforts are underway by the Save the Flamingo Association to address water quality threats at Kamfers Dam, with recent success. Collision of flamingos with power-lines and telephone lines are not adequately addressed, partly because of the unavailability of suitable marking devices to make cables more visible at night. Marking devices are currently being tested by Eskom and the Endangered Wildlife Trust.
Proposed
The recommendations in the International Single Species Action Plan for the Conservation of the Lesser Flamingo (Childress et al. 2008) must be implemented. In southern Africa, any current and potential threats to Etosha Pan and Sua Pan, the two southern African breeding sites, must be addressed and these pans must be protected and maintained in good ecological condition. In South Africa, the Kamfers Dam breeding island should be reconstructed and this wetland should be formally protected. Management plans for wetlands where large numbers of Lesser Flamingos occur, such as Kamfers Dam and Flamingo Pan, Welkom should be developed, especially to ensure that water quality issues and human disturbance issues are addressed. Key feeding sites should be identified, protected and monitoring programmes implemented. Alternative sites, such as the Welkom pans, should be considered for the construction of artificial breeding islands. Overhead cables, which result in mortalities through collisions, should be marked with suitable devices. Disturbance by low-flying aircraft must be prevented through legislation, planning, zoning and enforcement.
Research
* Accurate estimates of the population size in South Africa, and regular monitoring of numbers at important sites to determine trends, are required.
* Use of the object-based image-mapping to determine flamingo numbers at key pans and lakes, especially in the Great Rift Valley should be undertaken.
* Perform satellite tracking to assess movements within southern Africa and between southern and East Africa.
* Investigate the relationship between flamingo numbers and cyanobacteria species composition and abundance.
* Assess the impacts of surface water and groundwater abstraction on flooding period at breeding sites.
* Monitor community perceptions and involvement in co-management activities on and around breeding sites.
