Birdlife International factsheet for Hottentot Buttonquail
Hottentot Buttonquail is endemic to South Africa, and inhabits montane and lowland fynbos and coastal strandveld habitats (Debus & Kirwan, 2020). It was previously thought to have a small population size of 250-999 mature individuals (Birdlife International, 2020), but recent studies suggest the population may actually be much higher (Lee et al., 2018a; Lee et al., 2018b).
The main threat known to this species is the degradation of habitat by invasive alien species, agricultural pressures, and climate change (Lee et al., 2018b). Hottentot Buttonquail has been considered Endangered under the Criterion C2a(i), however this may no longer be tenable in light of new information. We have therefore reassessed this species here against all the criteria.
Criterion A: The population of Hottentot Buttonquail is suspected to be declining due to ongoing habitat degradation. However, there is no quantified estimate of the rate of reduction in either mature individuals over ten years (one generation length being 3.0 years; Bird et al. 2020)*, or (to the best of our knowledge) habitat quality. This species therefore cannot be assessed against criterion A.
Criterion B: The Extent of Occurrence (EOO) for this species is far greater than the 20,000 km2 threshold needed to trigger a threatened status under Criterion B1. Under IUCN guidelines, it is the EOO not the Extent of Suitable Habitat (ESH) that is used to assess a species against this criterion (IUCN Standards and Petitions Committee, 2019). Consequently, classifying this species as Vulnerable under criterion B1 based on the lower estimates of a 10, 377 – 41, 303 km² ESH as suggested in Lee et al. (2018a) is not appropriate. Hottentot Buttonquail may therefore be considered Least Concern under Criterion B.
Criterion C: Based on a population density of 0.032 individuals/ha, and an estimated ESH of 10, 377 – 41, 303 km², the most recent population estimates for this species is 33,206 – 132,169 individuals (Lee et al. 2018a), roughly equating to a population size of 22,248 – 88,553 mature individuals. Even assuming the true population size is towards the lower end of the estimate, this is high above the <10,000 mature individuals threshold required for classification as threatened under this criterion. Hottentot Buttonquail may therefore be considered Least Concern under this criterion.
Criterion D: The new population size estimates are way above the threshold (<1000 mature individuals) for classification as threatened under Criterion D. This species may therefore be considered Least Concern under this criterion.
Criterion E: To the best of our knowledge, no quantitative analysis has been carried out for this species, so Hottentot Buttonquail cannot be assessed against this criterion.
We therefore suggest that Hottentot Buttonquail be listed as Least Concern. We welcome any comments to the proposed listing.
Please note that this topic is not designed to be a general discussion about the ecology of the species, rather a discussion of the species’ Red List status. Therefore, please make sure your comments are relevant to the species’ Red List status and the information requested. By submitting a comment, you confirm that you agree to the Comment Policy.
*Bird generation lengths are estimated using the methodology of Bird et al. (2020), as applied to parameter values updated for use in each IUCN Red List for birds reassessment cycle. Values used for the current assessment are available on request. We encourage people to contact us with additional or improved values for the following parameters; adult survival (true survival accounting for dispersal derived from an apparently stable population); mean age at first breeding; and maximum longevity (i.e. the biological maximum, hence values from captive individuals are acceptable).
An information booklet on the Red List Categories and Criteria can be downloaded here and the Red List Criteria Summary Sheet can be downloaded here. Detailed guidance on IUCN Red List terms and definitions and the application of the Red List Categories and Criteria can be downloaded here.
Bird, J. P.; Martin, R.; Akçakaya, H. R.; Gilroy, J.; Burfield, I. J.; Garnett, S.; Symes, A.; Taylor, J.; Šekercioğlu, Ç.; Butchart, S. H. M. (2020). Generation lengths of the world’s birds and their implications for extinction risk. Conservation Biology online first view.
BirdLife International (2020) Species factsheet: Turnix hottentottus. Downloaded from http://www.birdlife.org on 27/04/2020.
Debus, S. & Kirwan, G.M. (2020). Hottentot Buttonquail (Turnix hottentottus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/53536 on 27 April 2020).
IUCN Standards and Petitions Committee, 2019. Guidelines for Using the IUCN Red List Categories and Criteria. Version 14. Prepared by the Standards and Petitions Committee. Downloadable from http://www.iucnredlist.org/documents/RedListGuidelines.pdf
Lee. A.T.K., Wright, D.R., and Wright, D.R., 2018a, Hottentot Buttonquail Turnix hottentottus: Endangered or just overlooked? Bird Conservation International, 29(1), pp. 136 – 143.
Lee. A.T.K., Wright, D.R., Wright, D.R., (2018b) Habitat variables associated with encounters of Hottentot Buttonquail Turnix hottentottus during flush surveys acrossn the Fynbos biome, Ostrich, 89:1, 13-18, DOI: 10.2989/00306525.2017.1343209