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The global population of the Hottentot Buttonquail Turnix hottentottus, a range-restricted Fynbos endemic, is estimated to be less than1 000 mature individuals with an estimated continuing decline of 20% within two generations, with no sub-populations likely to exceed 250 mature individuals, satisfying criterion C1 and C2 and justifying the assessment of Endangered.
The Hottentot Buttonquail is mostly restricted to the Fynbos Biome in Western Cape. It occurs from Cape Point (Table Mountain National Park), eastwards throughout the Cape Fold Mountains, with records from Hottentots Holland and adjacent ranges (e.g. near Somerset West, Kogelberg, Kleinmond and the Limietberg-Bain's Kloof areas; Taylor 2000b). It is also known from the Langeberg and Overberg regions (Bontebok National Park, De Hoop Nature Reserve, Potberg, Malgas and Wydgelee; Ryan and Hockey 1995). In the east of its range, it extends eastwards to the border of Eastern Cape along the Outeniqua, Kamanassie, Gamkasberg and Kouga ranges (Lee 2013). It was previously recorded as far east as Addo Elephant Park and Port Elizabeth, Eastern Cape (Grobler and Braack 1984) although there have been no recent records from this area (Allan and Colahan 1997). It also occurs in Strandveld along the West Coast, with occasional reports near Langebaan, and has been found breeding in Renosterveld near Melkbosstrand (Ryan and Hockey 1995). An earlier record from Graafwater near Lambert's Bay was in error (Ryan and Hockey 1995).
This species may be the most thinly distributed of South Africa's endemics and one of the least frequently recorded resident and breeding terrestrial birds in general (Lee 2013). Being so widely overlooked, the true extent of its distribution is unknown and future surveys are likely to reveal its presence in additional localities. The range of this taxon was estimated to be less than500 km2 by Taylor (2000), and SABAP2 data suggest an AoO of c. 1 600 km2.
The global population size is unknown. Brooke (1984) considered the species on the brink of extinction, while Hockey et al. (1989) described it as rare and highly localised but speculated that it may be common in remote mountainous areas. A survey by Ryan and Hockey (1995) in the Cape of Good Hope Nature Reserve (Table Mountain National Park) showed that the area may hold 350 (100-560) birds, occurring at 1 bird/5 ha in 25 km2 of suitable restionaceous Fynbos habitats, and making it the joint third most common bird species in such vegetation types. However, this census may represent an overestimate (Fraser 2014). Sampling method and time elapsed since the vegetation was last burnt influence population estimates, e.g. Fraser (1990) reported a density of only 1 bird/250 ha in similar habitat greater than 15 years after a fire. Densities in coastal Renosterveld are estimated at 1 bird/28-44 ha (Winterbottom 1968).
Taylor (2000) roughly estimated the global and regional population at less than 1 200 birds, but conservative extrapolations from the lower density estimates calculated by Fraser (1990) suggest a total population of only 400 individuals (Lee 2013). A precautionary estimate lies within the band 250-999 mature individuals, with no more than 250 individuals in the largest sub-population (BirdLife International 2014). Confidence in this population estimate is low and requires verification.
The population is suspected to undergoing a decline owing to on-going habitat loss and degradation (Taylor 2000).
A relatively high proportion of the favoured Mountain Fynbos vegetation inhabited by this species is under formal conservation (Low and Rebelo 1996, Barnes 1998), although commercial afforestation and invasion by alien woody shrubs pose serious threats (Ryan and Hockey 1995). While the Fynbos habitat of this species is naturally adapted to fire, inappropriate burning frequencies and intensities in lowland areas may still constitute a threat. Populations in coastal Strandveld are probably under greater pressure due to rapid urban development and agricultural expansion (Taylor 2000). The potential effects of climate change on this species have not been fully investigated, but may constitute a considerable cause for concern, given the Hottentot Buttonquail's naturally restricted range, mountain habitats and reliance on the Fynbos Biome (Simmons et al. 2004).
No conservation measures are currently underway.
Lee (2013) considered this species to be the South African endemic most deserving of a focused investigation into its conservation status. A Population and Habitat Viability Assessment (PHVA) is recommended, as is a Biodiversity Management Plan, culminating in a National Species Recovery Plan. Surveys are required to establish the abundance, distribution and precise habitat requirements of this species, before adequate conservation actions can be planned, as urged by Taylor (2000). Given that the species is highly sought-after by birdwatchers, organising controlled synchronised surveys by a large number of observers is a potentially effective method of surveying suitable habitats, and simultaneously raising funds and awareness, as has been done for the White-winged Flufftail Sarothrura ayresi. Mountaineers, hikers, land-owners and conservation officials should be encouraged to report any ad hoc sightings with supporting details to BirdLife South Africa and SABAP2. The species is poorly represented in reference and genetic collections, and specimens found dead should be donated to museums or other research institutions.
* Conduct population and density surveys in sites with historical and recent records.
* Identify and survey areas, which may hold important populations based on ecological parameters, possibly using remote sensing data.
* Quantify the extent of any seasonal movements through long-term temporal monitoring or stable isotope analysis.
* Research the exact habitat requirements of the species, focusing particularly on the effects of fire frequency, intensity and timing, on population health.
* Evaluate threats to the species and its habitat, and in particular the potential effects of climate change.