Rationale
(Changed due to Genuine (recent))
The scarce and nomadic Burchell's Courser Cursorius rufus is under-recorded in remote parts of its range; however, a 30% decrease in AoO, and a concurrent population decrease, qualifies it as regionally Vulnerable under criteria A2c and A4c. Accurate population estimates are not available, but it is likely that the regional population is less than 10 000 mature individuals with an estimated, continuing decline of at least 10% over the next three generations, the requirement for Vulnerable under C1. Furthermore, the scattered and severely fragmented distribution range suggests that no sub-population contains more than 1 000 mature individuals, as set out in criterion C2a(i).
Distribution
Burchell's Courser is near-endemic to southern Africa. It occurs widely but erratically in a highly fragmented pattern over much of the arid interior of South Africa and higher parts of the inland plateau, excluding Lesotho (Maclean and Herremans 1997). Extra-limitally, it is reasonably numerous and widespread in southern and western Namibia, especially along the eastern edge of the Namib and in Kaokoland, extending marginally into south-western Angola.
In South Africa, which encapsulates c. 40-60% of this courser's global distribution, both its range and abundance have declined dramatically in the past 50-150 years, with marked decreases in numbers or local extinctions in many areas. In the late 1800s, it was described as abundant on the Highveld of eastern South Africa (Stark and Sclater 1903), and it was still plentiful around Potchefstroom (the type locality) in the early 1930s (Lane 1933), which represents the last case of breeding in the former Transvaal province (Maclean and Herremans 1997). By the 1980s it was described as widely but sparsely and erratically recorded in the Transvaal, and possibly only present during drought years (Tarboton et al. 1987). It is now entirely absent from the northern parts of South Africa, with the exception of rare reports of transient, non-breeding and usually single birds, such as near Middelburg (1968), Pafuri (1980), and Beestekraal (c. 1980). A similarly worrying decrease occurred since the 1970s in KwaZulu-Natal, where it no longer occurs (Cyrus and Robson 1980, Maclean and Herremans 1997). Few recent records come from Eastern Cape, where the species was a locally common breeder until the 1940s. Records in northern and eastern Free State, where the species was previously considered common, are now almost negligible.
SABAP2 records show that it still persists in scattered locations in the dry interior, with concentrations of records in south-western Free State, Northern Cape and North West. However, it was recorded in few adjacent pentads, and the relatively large, contiguous populations apparent in the SABAP1 dataset appear to have become smaller and fragmented, but this impression may change as SABAP2 coverage of the interior improves. The species was previously considered a regular non-breeding migrant to the wheat-fields of Western Cape (Hockey and Douie 1995), but was not recorded there during the SABAP2 reporting period.
Population
The global and regional populations of Burchell's Courser have not been quantified (BirdLife International 2014). Obtaining accurate regional population estimates is very challenging owing to the vast, sparsely populated landscapes inhabited by this species, and the fact that its movements are poorly understood. It appears to be resident in some areas, given that environmental conditions remain suitable, but possibly undertakes regular migratory movements in parts of its range; however, as in many other arid-country species, it apparently also undergoes large-scale migratory wandering, and occasionally irrupts outside of its normal range. Nevertheless, the species is nowhere abundant, and even in the core of its current range, it remains elusive and localised. The size of the regional population is unknown, but is almost certainly less than 10 000 mature individuals. Confidence in this estimate is low and needs to be improved upon.
Population trend
Several authorities have expressed the view that the rapid range contraction and population reduction of this species is cause for concern, and that the near-endemic Burchell's Courser should be considered a conservation priority (Maclean and Herremans 1997, Lloyd 2005), particularly because the underlying causes of these declines are not currently understood. A c. 77% reduction in AoO between the two atlasing periods is apparent, and this suggests that a concurrent population decline of similar scale has also likely occurred. However, due to the fact that this species is certainly under-recorded in large sections of its range, a less severe decline of 30-50% within the past 10 years is more realistic. Furthermore, it is projected that this species will continue to decline by greater than 10% over the next three generations or 21.9 years (BirdLife International 2014). Confidence in this regional population trend estimate is medium.
Threats
The nature, extent and causes of the rapid decline in the range of Burchell's Courser are poorly understood (Maclean and Herremans 1997). Habitat loss is likely to be a significant contributor. Intensification of agriculture, and the accompanying use of irrigation, pesticides and fertilisers, and the shift from pastures to croplands possibly plays a role (Hockey and Douie 1995, Lloyd 2005). The species' historic range is likely to have contracted because of the reduction in the number of wild grazing ungulates, but this is partly compensated for by animal husbandry. The potential effects of climate change and desertification on Burchell's Courser have not been fully investigated; climate change is expected to impact heavily on species that inhabit the arid Nama Karoo and Succulent Karoo biomes (Simmons et al. 2004); however, its nomadic nature will possibly allow Burchell's Courser to cope with shifting biomes and climatic conditions.
Conservation
Underway
As this species was not previously considered a conservation priority, no conservation actions are currently underway.
Proposed
It is difficult to recommend targeted conservation measures before an in-depth understanding of the ecological requirements of this species is obtained, and the reasons for its suspected range and population decline are understood. Its long-term survival will likely be in the hands of private land-owners, and awareness campaigns and biodiversity stewardship programmes would be beneficial. Continued monitoring is essential: parts of the range remain unsurveyed or under-explored due to their remoteness, inhospitable climate and poorly developed infrastructure. Observers can be encouraged to visit such areas through coordinated atlasing expeditions, or through the provision of funding by atlas projects or conservation agencies. As Burchell's Courser is marginal in Angola, virtually extinct in Botswana, and at most a vagrant to Lesotho, its conservation is the sole responsibility of South Africa and Namibia; collaboration between these two countries is important.
Research
* Accurate regional and global population estimates are required.
* Better understanding of the extent of the species' seasonal and nomadic movements would be useful in developing management principles.
* Investigation into the compatibility of the species with different farming practices, particularly in terms of grazing levels, fire regimes and agriculture, is needed.
* Research on the extent, causes, nature and severity of the threats facing this species is urgently needed.
