Justification of Red List Category
This newly-described species has been assessed as Near Threatened on the basis that it has a very small range and probably has a small population, with continuing declines inferred to be taking place in the quality of habitat and in the number of mature individuals, but with no information on the sub-population structure or evidence to suggest that the population is severely fragmented or restricted to a few locations.
Given that it has a very restricted known range, within which the area of suitable habitat (forested canyons in limestone karst landscapes) is probably quite small, it is likely to have a small global population. No direct population estimate exists for the species across its range, but in Beanka Forest a survey found 4.7 individuals per km of transect (Ramasinatrehina and Raherilalao 2013). It is provisionally estimated to lie within the band for 2,500-9,999 mature individuals; it may, however, prove to be even smaller (F. Hawkins in litt. 2013).
The species is inferred to be undergoing continuing declines as a result of hunting pressure and habitat loss and degradation. The rate of decline has not been quantified but is not thought to be rapid.
This recently-described species is endemic to Madagascar, where it is known only from a very limited area of lowlands in the central west of the country, in Beanka and Bemaraha massifs (Safford and Hawkins 2013). The distance between the northernmost and southernmost known localities is 125 km, in a corridor rarely exceeding 5 km in width (Goodman et al. 2011, Safford and Hawkins 2013).
Known localities are between 100 and 320 m in areas of limestone karst with rock pinnacles known as tsingy (Goodman et al. 2011, Safford and Hawkins 2013). It occurs in dry deciduous forest, often in canyons or valleys closed or bordered by exposed rock (Goodman et al. 2011), where it feeds on the forest floor. The diet and breeding habits are unknown (Safford and Hawkins 2013).
It is likely to be very susceptible to hunting, which may be the greatest threat. Except in a few areas that have significant tourist traffic (near Antranombazaha, the access point to Antsalova, and the southernmost portion of Bemaraha near Bekopaka), the reserve is not well patrolled and access for hunting may be frequent (F. Hawkins in litt. 2013). In the north of the species's range the pinnacle karst landscape is known as a refuge for cattle bandits who live off animals and birds (F. Hawkins in litt. 2013). Much of the tsingy region is not thought to be vulnerable to human modification; however, limited habitat loss and degradation are thought to be taking place through shifting cultivation, conversion to pasture, wood harvesting and extraction of other forest resources. These threats are further limited by the low human population density and alleviated by the legal protection of the Tsingy de Bemaraha in a national park and strict nature reserve (del Hoyo et al. 1996, Taylor 1998, Rasoloarison and Pasquier 2003). However, in 1984 oil prospectors created a seismographic trail through the tsingy by means of explosives, thus facilitating access to areas that were previously impenetrable (Rasoloarison and Paquier 2003). Fires are set in the nature reserve in order to stimulate the growth of grass for grazing and to clear trails. Such uncontrolled fires and tree-cutting for house construction, fences and firewood are the primary causes of forest destruction (Rasoloarison and Paquier 2003), but Beanka is now a protected area which may reduce this (S. Goodman in litt. 2016).
Conservation and research actions in place
Much of the species's known range lies within the Tsingy de Bemaraha National Park, and the officially protected Beanka Forest (S. Goodman in litt. 2016).
Conservation and research actions proposed
Carry out further research to define the species's geographical range, estimate population densities across its range and its overall population size, and assess the scale of threats. Increase patrols of Tsingy de Bemaraha National Park and Beanka Forest to attempt to prevent hunting, burning and conversion of forest for grazing and shifting cultivation within the park boundaries.
Text account compilers
Westrip, J., Symes, A.
Hawkins, F., Safford, R., Goodman, S.
BirdLife International (2019) Species factsheet: Mentocrex beankaensis. Downloaded from http://www.birdlife.org on 19/10/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 19/10/2019.