Justification of Red List Category
This species qualifies as Critically Endangered owing to its extremely small population in a single area. Populations may occur in other areas, but these are likely to be small and declining.
This species has now been recorded from three locations with a minimum of 14 individuals known from Pindobas IV and Mata do Caetés, and confirmation that it occurs in Augusto Ruschi Biological Reserve. Additional forest occurs adjacent to these known sites which requires further survey work; hence the population is estimated at 50-249 individuals. This equates to 33-166 mature individuals, rounded here to 30-200 mature individuals. However, if further work either locates the species at additional sites or supports the assertion of Venturini et al. (2005) that the population may number fewer than 50 individuals, this estimate will require revision.
The species is suspected to be declining at a rate of 10-19% over 11 years (three generations), as a result of ongoing forest clearance owing to conversion to coffee plantations, mining activities and subsistence usage.
The species is currently known from Espírito Santo, Brazil, where small numbers have been recorded in Fazenda Pindobas IV since its rediscovery there in 1998, and in the Mata do Caetés area, Vargem Alta municipality, where up to nine individuals were recorded during visits in 2003-2007 (G. M. Kirwan in litt. 1999, 2012, Bauer et al. 2000, Venturini et al. 2002, Venturini et al. 2005) and there were further records in 2010, 2012 and 2013 (WikiAves 2013). Until its rediscovery, it was only definitely known from the 19th century type-specimen collected at Muriaé, Minas Gerais (though it has been hypothesised that this locality was actually Macaé in Rio de Janeiro [Pacheco 1999]), and a 1941 sighting of eight birds in Itarana municipality, Espírito Santo. Other sites are Augusto Ruschi Biological Reserve (Santa Teresa) and Santa Maria de Jetibá/Itarana montane areas, and there is a probable sighting from Fazenda Pedra Bonita, Minas Gerais (Bauer et al. 2000). However, subsequent surveys at the latter site have not been successful (Bauer et al. 2000). The general paucity of records must be a reflection of this species's extreme rarity and very patchy distribution; for example, during one year of recent research into its ecology, only 11 records were obtained.
It occurs primarily in the canopy of humid montane forest at elevations of 850-1,250 m (Bauer et al. 2000, Venturini et al. 2002, P. Develey in litt. 2007, 2008). The type-locality, Muriaé (if correct [Pacheco 1999]), is at 210 m. Altitudinal movements are plausible but the species is apparently resident at Fazenda Pindobas IV (Bauer et al. 2000) and in Vargem Alta municipality (P. Develey in litt. 2007, 2008). Birds forage in the interior of the crowns of tall trees, occasionally lower towards the forest edge (Bauer et al. 2000), and appear to favour moss and lichen-encrusted branches (Bauer et al. 2000). Between one and ten individuals are typically found together. It is associated with mixed-species flocks, having been recorded with over 30 different species (G. M. Kirwan in litt. 1999, Bauer et al. 2000, Venturini et al. 2002, Venturini et al. 2005, P. Develey in litt. 2007, 2008). Individual birds have been observed apparently acting as sentries for conspecifics within a flock (Venturini et al. 2005). The diet is reportedly arthropods (Bauer et al. 2000). Nest-building has been observed in late November (Venturini et al. 2002). It has been recorded living to over six years of age (Venturini et al. 2005).
Extensive deforestation within its range must have had a severe impact on this species. Forests within Itarana, where the species was recorded in 1941, have since been reduced to a number of small fragments. However, the species has been recorded in Eucalyptus spp. and Pinus spp. plantations using this suboptimal habitat while moving between fragments. Threats associated with the loss of forest include quarrying of limestone, granite and marble, illegal palm extraction, the expansion of coffee plantations, small-scale firewood-cutting, and larger-scale timber-cutting, including for charcoal production (Hilty 2011).
Conservation and Research Actions Underway
Considered Critically Endangered at the national level in Brazil (Silveira and Straube 2008, MMA 2014). It is protected under Brazilian law. The owners of Fazenda Pindobas IV have expressed interest in protecting the remaining native forest on their property (Venturini et al. 2002). The site of the 1941 record in Itarana is listed as an IBA owing to its importance for Atlantic forest endemics. Searches for the species have been conducted in other parts of Espírito Santo, Minas Gerais and Rio de Janeiro states (Venturini et al. 2005). A research project into the species's ecology was recently completed, and there is an Action Plan for the long-term conservation of the species (P. Develey in litt. 2007, 2008). In 2010, a 37,000 ha corridor was designated for the species with an objective to connect forest remnants through the development of forest conservation and restoration actions, promotion of sustainable activities and adequate soil management (BirdLife International 2010). Work is underway to create a Wildlife Refuge and private reserve encompassing known localities and connecting Forno Grande and Pedra Azul State Parks. The promotion of ecotourism in the area is ongoing (P. Develey in litt. 2014, SAVE Brasil 2015). Awareness-raising activities have also been conducted (P. Develey in litt. 2015, SAVE Brasil 2015).
Conservation and Research Actions Proposed
Monitor the population at Pindobas IV and Mata do Caetés (Anon. 2007). Survey the montane region of south Espírito Santo, and adjacent Minas Gerais and Rio de Janeiro, concentrating on elevations between 850 and 1,250 m and those sites which have previously been identified as potentially suitable for the species. Research ecology and seasonal abundance. Promote the creation of a Reserva Particular do Patrimônio Natural at the private farms where the species occurs (Anon. 2007). Raise awareness of environmental issues among local communities. Study alternative agricultural and wood production systems (Anon. 2007).
14 cm. Strikingly plumaged tanager. Silvery-white crown grades to grey in rest of upperparts. Black wings and tail. Black forehead and broad mask. White underparts with conspicuous, bright red throat and bib. Orangey iris and pinky legs. Voice Complex series of thin warbles, and double-whistle calls.
Text account compilers
Williams, R., Wright, L, Hermes, C., Ashpole, J, Bird, J., Pople, R., Sharpe, C.J., Symes, A., Clay, R.P., Wheatley, H.
Develey, P., Kirwan, G.
BirdLife International (2020) Species factsheet: Nemosia rourei. Downloaded from http://www.birdlife.org on 30/09/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 30/09/2020.