VU
Subdesert Mesite Monias benschi



Justification

Justification of Red List Category
This species is listed as Vulnerable because it has a small range, and continuing destruction of its habitat is suspected to be causing a significant population decline which is projected to continue into the future.

Population justification
Tobias and Seddon (2002) provided estimates of the species's population size using five methods, the most reliable of which yielded an estimate of 115,000 individuals. The other methods gave estimates ranging from 98,000-152,000 individuals, and these figures are taken as the species's population range. This is likely equivalent to 65,000-110,000 mature individuals.

Trend justification
This species is inferred to be declining owing to continuing habitat loss (Global Forest Watch, 2021), the likely rate of which is placed in the band of 30-49%.

Distribution and population

Monias benschi is restricted to a narrow coastal strip, originally 30-60 km wide and 200 km long, in south-western Madagascar between the Fiherenana and Mangoky rivers. It is common within suitable habitat, occurring at population densities of 0.2-0.3 individuals per ha (Seddon 2001). Although such habitat is threatened in the north-central, eastern and southern parts of this species's range, there is a fairly large intact block (c.2,500 km2) north of Manombo (Seddon et al. 2000). In 2002, the total population was estimated to be 115,000 individuals (Tobias and Seddon 2002).

Ecology

The species is restricted to dry, deciduous spiny forest, 5-15 m high, on sandy soil, with an abundance of Didierea trees, also tolerating highly degraded forest (Langrand 1990, A. F. A. Hawkins in litt. 1995, Morris and Hawkins 1998) and inhabiting very low-stature, sparse coastal scrub (Seddon et al. 2003). It feeds by picking invertebrates (and some seeds) from under the litter layer by a combination of shallow probing, flicking over dead leaves, and digging in sand. Although adapted for flight, the species in fact only flies to reach elevated roost sites and nests, and evade predators (Seddon et al. 2003). It breeds year-round in cooperative groups of 2-9 individuals that may include just one breeding pair or multiple male and female breeders (Seddon and Tobias 2013). These groups defend territories of 7-21 (mean of 14.9) ha (Seddon 2001, Tobias and Seddon 2002). In contrast to all other bird species in the same habitat, the species can continue to breed through the dry season and access food resources such as termites and buried invertebrate larvae (Seddon et al. 2003). The nest is a loosely woven platform of twigs, c.15 cm in diameter and c.5 cm deep, with a very shallow cup lined with fresh lichen. Breeding groups are known to construct up to five nests in a breeding season. One or more commonly two eggs are laid in each nest. Some populations are male-biased, perhaps due to higher female mortality during diurnal incubation and dispersal (Seddon et al. 2003).

Threats

Primary spiny forest cover declined by 15.6% between 1962 and 1999, and in the eastern part of this species's range, it declined by c.28% (Seddon et al. 2000; Tobias and Seddon 2002). Such clearance is mainly for slash-and-burn cultivation of maize and for charcoal production (Seddon 2001), and more locally for construction material and commercial timber (Seddon et al. 2000). Data from Global Forest Watch (2021) suggests that the rate of deforestation across this species's range remains high. Predation by dogs and trappers occurs, and introduced rats Rattus may pose a threat, at least locally (Langrand 1990). Climate change may affect this species, both through effects on its habitat, and indirect effects as climate change affects human populations where this species is found (Segan et al. 2015).

Conservation actions

Conservation Actions Underway
The spiny forest of south-west Madagascar has been identified as the biogeographic region in greatest need of additional reserves nationally (Du Puy and Moat 1996). The northern part of this region, to which the species is restricted, is entirely unprotected and is suffering the most rapid degradation (Seddon et al. 2000). Potential conservation measures have recently been recommended for the area, designed in consultation with local communities (Seddon et al. 2000).

Conservation Actions Proposed
Conduct regular surveys to monitor population trends. Continue to monitor the clearance of spiny forest. Establish a coordinated network of community-based conservation areas, including a large protected area (Seddon et al. 2000). Improve agricultural efficiency and control charcoal production.

Identification

32 cm. Strange, long-legged, rail-like terrestrial bird. Brownish-grey on back and crown, with long, dark-bordered, whitish supercilium and long, decurved blackish bill. Tail is rather long and full, legs are fairly long and pinkish. Males are whitish below, marked with black crescents, while females are variably mottled rufous-brown and black. Similar spp. From terrestrial couas Coua by long, decurved bill, pale supercilium, and either largely reddish (female) or mottled whitish (male) breast. Voice Loud, communal song. Call when disturbed is nak! nak! Hints Occurs in groups in spiny, subdesert forest.

Acknowledgements

Text account compilers
Clark, J.

Contributors
Ekstrom, J., Evans, M., Hawkins, F., Khwaja, N., Langrand, O., Seddon, N., Shutes, S., Starkey, M., Symes, A., Taylor, J., Tobias, J. & Westrip, J.R.S.


Recommended citation
BirdLife International (2022) Species factsheet: Monias benschi. Downloaded from http://www.birdlife.org on 28/09/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/09/2022.