Current view: Data table and detailed info
Taxonomic note
Monotypic.
Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
IUCN Red List criteria met and history
Red List criteria met
Red List history
| Migratory status |
not a migrant |
Forest dependency |
does not normally occur in forest |
| Land-mass type |
continent
|
Average mass |
- |
Population justification: The most recent published Blue Crane population estimates for South Africa are those of McCann et al. (2007), with a minimum of 25,520 individuals. Of these, the Western Cape held the largest numbers, 12,095 individuals, with 10,822 in the central Karoo and 2,616 in the eastern grasslands, the traditional stronghold (McCann et al. 2007). The disconnected population in northern Namibia is very small, with annual maxima not exceeding 35 in recent years: 32 individuals was the high in 2018, 33 in 2019 (Namibia Crane Working Group 2018, 2019, Scott et al. 2019). The minimum estimate for the global population size is therefore c. 25,550 individuals.
A recent, unpublished, Distance-based survey in the Western Cape suggests that numbers here may be higher than those estimated by McCann et al. (2007), with possibly up to 25,000 birds in the Western Cape alone (C. Craig in litt. via IUCN SSC Crane Specialist Group 2020). This is a very preliminary estimate, assuming presence at equivalent density across all pasture/fallow land in the Western Cape, and would represent a rapid increase in this population up to the recent past. Assuming stability in the other regions, the maximum population size could be c. 38,500 individuals, while if a further assumption is made that the proportions between the three areas have remained the same (i.e. all have increased) then the potential maximum is 45,132 individuals (C. Craig in litt. via IUCN SSC Crane Specialist Group 2020).
The total population size is therefore estimated at 25,550 - 45,132 individuals (here rounded to 25,000 - 46,000 individuals), which is assumed to equate to roughly 17,033 - 30,088 mature individuals, here rounded to 17,000 - 30,000 mature individuals.
While numbers were previously increasing in the Western Cape, recent analysis of driven transect data suggests that this population is now declining by 2-3% annually (IUCN SSC Crane Specialist Group, International Crane Foundation, Endangered Wildlife Trust, K. Shaw & P. Ryan in litt. 2020). If this rate persists, over the next three generations (37.5 years), dependent on the proportion of the whole population that this represents, the future three-generation reduction would be suspected to fall between 24.9-37.6%.
Trend justification: In South Africa, aerial surveys conducted by the Endangered Wildlife Trust and Ezemvelo KZN Wildlife suggest the population in KwaZulu Natal is increasing steadily, and increased by more than 35% in the decade prior to 2013 (Smith & Craigie 2012). Numbers in the south and south-western Western Cape have increased as the species has expanded into agricultural areas (Hofmeyr, 2012), and a significant increase in densities was recorded through the Coordinated Avifaunal Roadcount (CAR) driven transect surveys between the 1990s and 2019 (Young & Harrison 2020).
However, a separate assessment of the last ten years of the CAR summer surveys (IUCN SSC Crane Specialist Group, International Crane Foundation, Endangered Wildlife Trust, K. Shaw & P. Ryan in litt. 2020) indicates that these increases have reversed; the Overberg population increased by c. 13% annually for 17 years to 2010, but has declined by 4% per year between 2011-2019; the Little Karoo population declined by 2% per year from 2010-2018 (although the highest number of cranes in 19 years of the Little Karoo survey was observed in 2019: CAR data supplied by C. Craig in litt. 2020); and the Swartland population appears to have stabilised after previous increases, only increasing by 0.05% annually between 2007-2017. Great caution is advised when interpreting these trends, as participation in the CAR has declined considerably since 2010 (C. Craig in litt. 2020) and the number of birds appears to be correlated with total distance surveyed.
A model of potential population trajectories indicated that should breeding success reduce, which is conceivable as current values are thought to be high (T. Smith in litt. 2018, K. Morrison in litt. 2020), current rates of adult mortality would be unsustainable (Pettifor et al. unpublished [2007]) and the species would decline again. Given the long generation length of 12.5 years (Bird et al. 2020), and the IUCN SSC Crane Specialist Group, International Crane Foundation, Endangered Wildlife Trust, K. Shaw & P. Ryan in litt. (2020) analysis of recent data, the previously increasing (and suspected to be much larger) Western Cape population is now suspected to be decreasing by 2-3% a year (IUCN SSC Crane Specialist Group, International Crane Foundation, Endangered Wildlife Trust, K. Shaw & P. Ryan in litt. 2020). At this rate, over the next three generations (37.5 years), it is suspected that the future three generation reduction will exceed 30% over the next three generations, although this depends on the proportion of the total population that this part of the population represents, and whether the reduction will continue at this rate for the whole period. At the maximum values provided (C. Craig in litt. [2020] via the IUCN SSC Crane Specialist Group: total population 45,132 individuals, with 25,000 in the Western Cape, 13,900 in the Karoo and 6,000 in the grasslands), then a 2-3% decline in the Western Cape population would result in a decline of 29.3-37.6% over 37.5 years. At the values provided by McCann (2007), the last published estimate, a 2-3% annual decline would result in a 24.9-32% reduction over three generations.
These rates of decline have previously been recorded. In the last quarter of the 20th century the national population was estimated to have fallen by half (Archibald and Meine 1996, Barnes 2000). In the former stronghold of the species, the grasslands, the species has continued to decline slowly throughout, at a rate estimated at 15% over the last three generations (Shaw et al. 2015). A comparison between the first Southern African Bird Atlas Project (1987-1992) and the second (2007-2009), shows that reporting rates declined in 63% of the units surveyed, mainly in the grasslands (Hofmeyr, 2012).
The population in the central Karoo region of South Africa is currently stable or maybe slightly increasing, as the species has adapted to the pasture land use system (Allan 2005, McCann et al. 2007), although it may have increased in the Karoo since the 1980s (Shaw et al. 2015). Eastern Cape Karoo and Eastern Cape Coastal CAR routes indicate stable or slightly increasing trends between 1999 and 2017 (C. Craig in litt. 2020).
In Namibia the population has been undergoing a steady decline to very low numbers since the 1970s (Simmons 2015, A. Scott and M. Scott in litt. 2018), with recent counts around 32-33 (Namibia Crane Working Group 2018, 2019, Scott et al. 2019).
The drivers of the apparent recent reversal in the trend of the large Western Cape population are uncertain (C. Craig in litt. 2020). The most plausible mechanism is through a reduction in breeding success due to predicted changes in the agricultural landscape with climate or socio-economic change (K. Morrison in litt. 2016), in tandem with estimated high mortality (notable of adults) from infrastructure collisions (especially powerlines; Shaw et al. 2010) and accidental poisoning through the use of poisoned bait to protect crops (T. Smith in litt. 2018, Morrison et al. 2019). Adult survival is estimated to be significantly lower in the Western Cape than in the Karoo, while juvenile and immature survival were higher (van Velden et al. 2017, T. Smith in litt. 2018). If subadult survival/productivity falls, a demographic model for the species predicts there will be a rapid population reduction where adult survival is low (Pettifor et al. unpublished [2007]).
Country/territory distribution
Important Bird and Biodiversity Areas (IBA)
Recommended citation
BirdLife International (2024) Species factsheet: Blue Crane Anthropoides paradiseus. Downloaded from
https://datazone.birdlife.org/species/factsheet/blue-crane-anthropoides-paradiseus on 22/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/11/2024.
