Current view: Data table and detailed info
Taxonomic note
Chlamydotis undulata and C. macqueenii (del Hoyo and Collar 2014) were previously lumped as C. undulata following Sibley and Monroe (1990, 1993).
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 |
nomadic |
Forest dependency |
does not normally occur in forest |
| Land-mass type |
|
Average mass |
- |
Population justification: In the mid-1990s this species' population was estimated to number 10,550 individuals (Goriup 1997). The population of nominate undulata in the mid-1990s was estimated to be at least 9,800 individuals, of which over 50% were in Algeria, 30% in Morocco and 10% in Libya (Goriup 1997). No overall estimate of the size of the wild population in North Africa has been made since due to the difficulty in adequately sampling across the range. Detailed population monitoring using point counts has been undertaken within the Emirates Center for Wildlife Propagation (ECWP) intervention area in eastern Morocco, which totals around 50,175 km2 (Hardouin et al. 2015, Monnier-Corbel et al. 2022). The first assessment of density returned values of 0.05 individuals per km2 in hunting areas and 0.1 individuals per km2 in protected areas, giving an estimate of around 3,400 individuals in the whole area (Hardouin et al. 2015, Dolman et al. 2021, Monnier-Corbel et al. 2022). If this value is used as a precautionary minimum for half the population size for Morocco (as the species occurs across much of the thorn-scrub desert in southern Morocco, a much larger area but likely at lower densities), then if the Moroccan total represents approximately 30% of the global population a minimum value for the latter would be around 22,600 individuals, more than double the value suggested by Goriup (1997).
Within the ECWP numbers of birds released increased annually (ECWP 2014, Hardouin et al. 2015, Monnier-Corbel et al. 2022) and this correlates with a rapid increase in the density recorded in surveys, up to 0.76 and 0.84 in 2010 (Hardouin et al. 2015, Monnier-Corbel et al. 2022), corresponding to a peak abundance estimated at 32,401 individuals (95% confidence limits 24,608-42,662) across the ECWP area (Monnier-Corbel et al. 2022). This population appears to have then severely declined in the following two years (although Monnier-Corbel et al. [2022] report no significant trend) with the estimated number of individuals in 2013 at 10,409 (8,667-12,500) (data from Monnier-Corbel et al. 2022). The total number released into this area actually exceeded the estimated population in both 2013 and 2014: subsequently (data to 2018) the population has been comparatively stable, ranging between 13,207-16,329 individuals but with 12,350 and 11,000 released in 2015 and 2016, and 7,050 and 6,700 released in 2017 and 2018 (data from Monnier-Corbel et al. 2022). Monnier-Corbel et al. (2022) conclude that the population within the ECWP does not currently meet criteria for viability and self-sufficiency, mirroring a conclusion published in a 2017 thesis (Bacon 2017) that the 'North African Houbara bustard population is not viable without reinforcement interventions in the long run'. Populations that are regularly supplemented from captive stock to prevent imminent extinction (i.e. within 10 years), as appears to apply within the ECWP area, are not considered in the determination of the species' Red List status except in consideration of species Extinct in the Wild (IUCN 2022). This situation has arisen only recently (Monnier-Corbel et al. 2022) and has had the effect of removing a significant part of the population from the scope of this assessment within the past three generations.
There is also evidence of a contraction in the range and reports of it becoming more difficult to find where it does still occur. It is now very rare in Western Sahara, having suffered a rapid decline in the 20th century (Bergier et al. 2017). In Tunisia it is now restricted to remote areas in the extreme south (Chammem et al. 2012) which suggests there are far fewer here than previously suspected (D. Jurek in litt. 2015) and there may only be a few hundred individuals in the country. Very little information is available from Libya, where there have been releases (e.g. 300 in 2010-11) (Dolman et al. 2021). There is a very large extent of potentially suitable habitat in Libya, but equally there is hunting and no information on impacts on either population size or demography. Given the sheer number of released individuals it is now very difficult to assess the wild population size in Morocco and adjacent areas of Algeria. The latter has received relatively few released individuals (although the number that may have dispersed into Algeria from Morocco is unknown and more releases are taking place) and possesses a very large extent of suitable habitat. There do not appear to be any data on hunting levels in Algeria but Berredjouh et al. (2016) noted hunting parties may last more than a month and take several hundred or even a few thousand individuals. The same study found the species was rare but a population remains in Ouled Djalel, Besbes and Ras Elmiaad regions in Biskra province in central Algeria (Berredjouh et al. 2016, Berredjouh 2021). There have never been accurate data from Mauritania, where some releases have taken place, but it is suspected that any population here is small and also subject to an unknown level of hunting.
Applying a three-generation reduction of between 30-50% as suspected to the tentative 2001 value of around 22,000 individuals results in a 2022 total between 10,450 and 14,975 individuals. This is an uncertain value given the lack of quantified data for the majority of the range, and may be a considerable underestimate. There is an urgent need for a rangewide assessment of the current wild population size, and establishing the existing population size is a pre-requisite for each area targeted for large-volume releases to allow evaluation of the impact of releases. While the ECWP release area may no longer be considered part of the wild population for this assessment, there are no barriers to the dispersal of released birds into surrounding, unmonitored areas and many further releases have been made in other locations, notably in Algeria but also in Mauritania and Libya (Dolman et al. 2021). No data on the pre-release population in these areas appears to be available and there does not appear to be any ongoing monitoring equivalent to that within the ECWP. While a tentative wild number of individuals is presented here, largely in order to consider plausible population reduction scenarios to inform this assessment of extinction risk, the true number currently living in North Africa (wild, released and offspring of released birds) and how that relates to the wild population size is highly uncertain.
The Canary Islands subspecies C. u. fuertaventurae, is confined to the eastern Canary Islands with a population estimated at 537-577 individuals (Ucero et al. 2021). Most are now on Lanzarote, where the population was almost extirpated due to persecution in the 20th century (Horreo et al. 2023) but since hunting was banned in 1971 the population has increased (Schuster et al. 2012, Horreo et al. 2023) to 440-452 adult individuals in 2018 (Alonso et al. 2020), with 460 reported in 2020 (de Colsa et al. 2022). A total of 85-109 are present on Fuerteventura (Ucero et al. 2021), although 160 individuals were estimated 2020 (de Colsa et al. 2022). Not much more than a handful remain on La Graciosa with 12-16 estimated by Ucero et al. (2021). Previous estimates are difficult to compare, with changes to methodologies used and discrepancies in coverage confounding efforts to census what is a difficult species to monitor. In the mid-1990s it was estimated at 527 birds, with 241 on Fuerteventura, 268 on Lanzarote and 18 on La Graciosa (Martin et al. 1997) while two studies in the early 2000s placed the population around a thousand birds: Carrascal et al. (2006, 2008) estimated 108-252 birds on Fuerteventura, 272-801 on Lanzarote and 3-10 on La Graciosa whilst Lorenzo et al. (2007) estimated the population at c.1,000 birds across all the islands.
Bearing in mind the caveats given above, the overall global population is suspected to fall between 11,000-30,000 individuals.
Trend justification: The species showed a steady decline of c. 25% in the 20 years preceding 2004 (F. Launay pers. comm. 2004). Subsequently reports are of it becoming more difficult to find (D. Jurek in litt. 2015) and the severity of threats including hunting pressure and habitat loss and degradation was considered likely to be causing rapid declines (Chammem et al. 2012, Banos-González et al. 2016, Bacon et al. 2019), suspected to exceed 30% over a three generation period (BirdLife International 2016). This rate had the potential to slow as a result of a captive breeding and release programme in eastern Morocco and western Algeria (Lacroix et al. 2003, O. Combreau in litt. 2012), but the very large numbers of individuals released coupled with hunting have resulted in this population being assessed as no longer a viable self-sustaining population (Bacon 2017, Monnier-Corbel et al. 2022). In 2001, before the intensification of releases, this population was estimated at 3,400 individuals (Hardouin et al. 2015) suggesting a rough minimum global population size around 22,600 individuals (see notes under Population Size).
Assuming population reductions have proceeded at between 30-50% over three generations since 2010, bounds of the population size in 2022 would fall between 10,500-15,400 individuals (exponential model of reduction), or 10,600-15,470 individuals (linear reduction). The managed subpopulation within the ECWP requires subtracting from this value, but must also have this assumed rate of decline applied to be an appropriate counterfactual, hence would be between 1,640 (50% reduction) and 2,325 (30% reduction) individuals in 2022. Subtracting this from the global total gives a mean rate of reduction over the past three generations of 40% (40-57%) (where the maximum rate is based on a linear model of reduction). It is noted that the causes of the removal of the ECWP population are reversible and understood, however the driver of the reduction either overall or for this population has not ceased.
Given that the rate of reduction was suspected to have exceeded 30% over three generations only recently, the best value is still considered to be within the lower half of the range. Therefore, with the additional removal of the managed subpopulation, the rate of reduction is suspected to have fallen between 40 and 50% over the past three generations, and also to fall in this range over the three generations beginning 2013, the year where the ECWP population was excluded on the basis that this was the first year that releases exceeded the estimated population size.
Future rates of reduction will be dependent upon the maintenance of the remaining mainland population as unmanaged and wild. One additional area becoming a managed subpopulation within the current three-generation period would tip these tentative calculations into indicating a rate of reduction in excess of 50%, and employing large-volume releases of captive-reared birds across the whole mainland range risks all individuals being classed as managed subpopulations.
The Canary Islands population is now thought to be stable or declining slowly (de Colsa et al. 2022, Ucero et al. 2021), though trends have been hard to recover from monitoring (Geary et al. 2022) and reports to the European Commission indicated an increasing trend until recently (BirdLife International 2021). On Lanzarote the species was almost extirpated by the mid-20th century with only 20 birds estimated in 1979 (Lack 1983) but has recovered notably since to around 450 individuals (de Colsa et al. 2022, Ucero et al. 2021, Horreo et al. 2023). It is uncertain whether this population will continue to grow, while on Fuerteventura a slow long-term decline (Carrascal et al. 2008, Horreo et al. 2023) appears to be driven by habitat degradation due to aridity and abandonment of traditional agriculture, which are suspected to be causing observed poor breeding success (Horreo et al. 2023).
Country/territory distribution
Important Bird and Biodiversity Areas (IBA)
Recommended citation
BirdLife International (2024) Species factsheet: African Houbara Chlamydotis undulata. Downloaded from
https://datazone.birdlife.org/species/factsheet/african-houbara-chlamydotis-undulata on 23/11/2024.
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 23/11/2024.
