Justification of Red List Category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km² combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). For these reasons, the species is evaluated as Least Concern.
A 1994 survey resulted in an estimate of c.310-480 birds, or 0.021-0.036 birds/ha, in 25 km2 of montane fynbos habitat in the Cape of Good Hope Nature Reserve (Ryan and Hockey 1995, Lee 2013). The lack of records suggest that this may be an overestimate, and extrapolation of a much lower density estimate of 0.004 birds/ha from a 1990 study would result in a total population across the Western Cape of just 400 birds (Fraser 1990; Lee 2013). Further survey work by Lee et al. (2018a, 2018b) in 2016 found a population density of 0.032 individuals/ha, and an estimated Extent of Suitable Habitat of 10,377 – 41,303 km2 (median 27,855 km2). The most recent population estimate is therefore 33,206 – 132,169 individuals (median 89,136), roughly equating to a population size of 22,248 – 88,553 mature individuals (median 59,721). However, the species is likely to have a very dynamic population as a result of the Fynbos ecosystem being fire-driven (A. Lee in litt. 2021).
The population is suspected to be in decline owing to on-going habitat loss and degradation (Barnes 2000, Madge and McGowan 2002), including declines in suitable area due to agricultural land conversion and alien vegetation encroachment (A. Lee in litt. 2021).
Turnix hottentottus, as defined following the split of T. nana, is found in the Western and Eastern Cape provinces of southern South Africa, wherever there is fynbos habitat of the right structure. Modelling conducted by Lee et al. (2018b) estimated the range of suitable habitat to be 10,377-41,303 km2. Species distribution models also suggested a high probability of occurrence associated with the Agulhas plain (Lee et al. 2018b) .
This species is usually solitary, but can be found in pairs during the breeding season (Lee 2013). It is considered restricted to the fynbos biome of South Africa, a heath-like, fire-driven ecosystem, dominated by Proteaceae, Ericaceae and Restionaceae plant families. Surveys suggest that this species may prefer areas of low gradient terrain, and fynbos that has experienced a fire cycle 2-5 years previously. Individuals may avoid older vegetation that has not experienced a fire cycle in more than 10 years (Lee et al. 2018b). This may be because older vegetation becomes more dense and difficult for terrestrial birds to navigate (Madge and McGowan 2002). The species is also found in coastal strandveld, in similarly structured habitat (Barnes 2000, Madge and McGowan 2002). Recorded nesting in September-December (Madge and McGowan 2002, Peacock 2015).
Although mountain fynbos habitat is generally better protected than that in the lowlands, potential threats include an increase (or suppression) in fire frequency, commercial afforestation, the spread of invasive plants, and agricultural and urban expansion. Habitat preference models by Lee et al. (2018b) associated this species with land that is easy to convert to agriculture, and in its stronghold on the Agulhas plain, the species was more frequently encountered in protected areas than the surrounding habitat. Climate change may prove to be an issue for this species given its restricted biome, but the potential impacts have not fully been explored yet (Simmons et al. 2014).
Conservation and research actions underway
This species was the target of a major survey by BirdLife South Africa and University of Cape Town, but as of 2020 is not currently receiving any research attention.
Conservation and research actions proposed
Survey sites with historical records to obtain density estimates throughout its range to better estimate the total population. Continue to monitor threats to species and its habitat. Lobby for urgent protection for unprotected sites with recent records. Produce a Population and Habitat Viability Assessment and a Biodiversity Management Plan, with a view to producing a National Species Recovery Plan (Peacock 2015).
14-16 cm. A typical small, dumpy Turnix buttonquail with very short tail and short, round-tipped wings. Broadly barred or black-spotted on breast and flanks and upperparts dark brown barred black. Similar spp. T. nana has unspotted underparts below breast in male, and almost entirely unspotted underparts in the female. Also has the lower back and rump almost black, contrasting with the rest of the upperparts. Small Buttonquail T. sylvatica has a pale central crown stripe and is generally more scalloped above. Voice. A low "hoom hoom hoom" with very little pause between notes.
Text account compilers
Rotton, H., Clark, J.
Butchart, S., Ekstrom, J., Khwaja, N., Lee, A., Martin, R., Symes, A., Taylor, J., Westrip, J.R.S. & Wright, D.
BirdLife International (2022) Species factsheet: Turnix hottentottus. Downloaded from http://www.birdlife.org on 07/10/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 07/10/2022.