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The regional population of the stately Wattled Crane Bugeranus carunculatus satisfies the population-size criterion for regionally Critically Endangered, with a <250 mature individuals occurring in the region, the vast majority of this number occurring in the wetlands of KwaZulu-Natal.
The Wattled Crane is restricted to Africa, with three sub-populations recognised (Beilfuss et al. 2007). The largest sub-population of c. 7 000 birds is located in the central southern African states of Zambia, Botswana, Angola, Democratic Republic of Congo, Tanzania and Zimbabwe. Birds occurring within this core area undertake movements in response to environmental conditions (Allan 2005). Two smaller populations of similar size occur in Ethiopia and South Africa (Beilfuss et al. 2007). South Africa’s population of Wattled Cranes was historically widespread and found in all four of the former provinces. However, the species’ range has reduced significantly, resulting in it being confined to the eastern grasslands of South Africa, with the core of the population located in the KwaZulu-Natal Midlands. The two most important protected sites are Umgeni Vlei (14-16 mature individuals) and Ntsikeni Vlei (8-10 mature individuals) followed by Mvoti Vlei, Karkloof, Kamberg and Highmoor. A few pairs of Wattled Cranes are found in the grasslands of northern Eastern Cape around Ugie and Maclear (6-10 mature individuals) and the Highveld grasslands of Mpumalanga and eastern Free State (10-20 mature individuals) (McCann 2003).
In South Africa, breeding pairs are largely sedentary, while non-breeding birds or ‘floaters’ tend to move up to 130 km away from the breeding sites (Johnson and Barnes 1991). There is no evidence of movement in and out of the region (McCann 2001) and the regional population is therefore considered a single sub-population of the African population. The species is regionally extinct in Swaziland (Monadjem et al. 2003). The last record of Wattled Crane in Lesotho was at Sehlabathebe National Park in the early 1980s (Osborne and Tigar 1990).
The global population has been quantified at c. 8 000 mature individuals (Beilfuss et al. 2007). In 1980, the regional population was estimated at c. 380 mature individuals (McCann et al. 2000). The results of the annual crane census in 1999 put the estimated population at 235 individuals (McCann 2001). Since 1999, the population has increased slightly with an estimated 245 mature individuals recorded (Endangered Wildlife Trust unpubl. data). Confidence in this regional population estimate is high.
The global population has undergone a rapid decline over the past three generations in nine of the 14 range states (Beilfuss et al. 2007). Beilfuss et al. (2007) estimated that the regional population of Wattled Crane had declined by 36% over the past three decades with a dramatic restriction in range. Extrapolating this over three generations (39 years) would result in a decline in the regional population by 42%. Confidence in this estimate is high.
The primary threat and main cause of decline over the past three decades has been the loss and degradation of permanent, palustrine wetlands through intensified agriculture, afforestation, dam construction, alien plant infestation and draining of wetlands (McCann et al. 2000). Grassland areas surrounding breeding sites are vital for foraging and cover for chicks. Habitat loss in KwaZulu-Natal and Mpumalanga continues at an alarming rate due to agriculture, forestry and mining (Allan et al. 1997). Inappropriate management of wetlands with regard to timing and frequency of burning is a threat to nesting Wattled Cranes (Bentos 2002). Wetlands are used as fire breaks on agricultural and forestry properties and burning often coincides with the peak period for Wattled Crane breeding, leading to loss of eggs and chicks. Wattled Cranes are particularly prone to collisions with overhead power-lines, especially those located between breeding, roosting, and foraging sites (Smallie 2012). The threat of illegal removal of eggs and or chicks from the wild is relevant and strict trade control measures need to be implemented (CITES 2004).
Crane conservation efforts in the region started in the 1980s due to significant population declines of the three crane species found in South Africa. Ezemvelo KwaZulu-Natal Wildlife, a government conservation body, protects and conserves important crane habitats through its network of nature reserves. Ezemvelo KwaZulu-Natal Wildlife also undertakes annual aerial surveys of cranes within the province. The KwaZulu-Natal Crane Foundation, which was founded in 1989, works with land-owners raising awareness and encouraging sustainable management practices. The Endangered Wildlife Trust began crane research and conservation action in 1994. Efforts to date have included monitoring, power-line investigations and mitigation, crop damage research and mitigation, awareness creation and conservation of key areas through promotion of sustainable management and, more recently, inclusion of key areas into the Biodiversity Stewardship Programme. The Wildlands Conservation Trust, a KwaZulu-Natal based NGO, works closely with Ezemvelo KwaZulu-Natal Wildlife and has been involved in purchasing important wetland and crane habitats within KwaZulu-Natal. The Johannesburg Zoo coordinates the Wattled Crane Recovery Programme, which is a captive-rearing programme. In 2000, a Wattled Crane PHVA was completed, which saw the formation and formalisation of the Wattled Crane Recovery Programme, and in 2010 there was a review of the PHVA to determine progress. Endangered Wildlife Trust’s African Crane Conservation Programme, with input from other stakeholders, is in the process of completing a Biodiversity Management Plan for all three species of cranes in South Africa.
In 2000, Eskom and the Endangered Wildlife Trust completed the marking of power-lines in close proximity to active Wattled Crane nest sites. However, it is recommended that this project is revisited to determine if any new sections of lines need to be marked or if previously marked sections need refitting of bird diverters. Supplementation of the wild population is recommended and this can be achieved through the Wattled Crane Recovery Programme. Securing key breeding and foraging sites, through Biodiversity Stewardship agreements or land acquisition, is strongly recommended to prevent loss of crucial habitat. All wetlands that Wattled Cranes use or have used in the past for nesting should be assessed, and recommendations put forward for rehabilitation.
* An extensive investigation into disease risks and potential impacts on regional Wattled Crane populations is required.
* An understanding of the dynamics of the double-egg clutch strategy practised by Wattled Cranes is needed.
* A rapid-assessment technique for wetland suitability for Wattled Cranes should be developed.