Justification of Red List Category
This species is listed as Critically Endangered because it is thought to have an extremely small population, which occupies a very restricted range in which habitat is declining in quality, extent and area. Further conservation actions are required as a matter of urgency if this species is to survive.
It is thought that fewer than 30 individuals persist (Pereira et al. 2014). It is therefore placed in the band 1-49 mature individuals.
This species is suspected to be declining owing to the on-going and rapid loss of remaining forest habitat. Habitat loss at Murici is ongoing (SAVE Brasil 2016, Global Forest Watch 2018). The lack of recent records outside Murici suggests that the population outside this site has declined, if not disappeared (B. Phalan in litt. 2018).
Myrmotherula snowi has only been recorded in Alagoas and Pernambuco states, north-east Brazil. It was first discovered at Murici (Alagoas) in 1979, when an adult male and two adult females were collected (Teixeira and Gonzaga 1985). An additional juvenile male was collected in 1984, and subsequent records throughout the 1990s, in 2000 and in 2009 have only found the species in very small numbers (Whitney and Pacheco 1995, 1997, J. M. Goerck in litt. 1999, A. Whittaker in litt. 1999, J. M. Goerck in litt. 2000, F. Olmos in litt. 2002). The species has also been recorded in Pernambuco at Mata do Estado (São Vicente Férrer) in 1999 (F. Olmos in litt. 2002, Roda et al. 2003), Frei Caneca in 2003 and 2007 (Mazar Barnett et al. 2005, Albano 2007) and Mata do Benedito (Engenho Jussará) in 2005 and 2006 (Albano 2006, S. Roda in litt. 2007, Roda et al. 2009). Since 2007 the species has not been recorded outside Murici, despite all other known sites having been revisited, and it is not known whether the species persists outside Murici (B. Phalan in litt. 2018). Despite extensive playback searches, no new sites for this species have been found (Pereira et al. 2014). Remaining habitat is very limited and severely fragmented.
It forages in pairs and small mixed-species flocks in the middle strata of upland semi-humid forest at 500-790 m (Roda et al. 2011). Birds range from 1.5 to 9 m above ground, keeping mostly at 5-8 m (Whitney and Pacheco 1997). Foraging flocks reportedly include White-flanked Antwren M. axillaris and a variety of other formicariids, although observers at Mata do Estado failed to locate it in mixed flocks (Roda et al. 2003). The diet consists of arthropods, including spiders, beetles, ants and cockroaches. Breeding probably occurs in February, and juveniles have been recorded in May.
Forest at Murici has been reduced from 70 km2 in the 1970s to 30 km2 of highly disturbed and fragmented habitat in 1999 (J. M. Goerck in litt. 1999, 2000), largely as a result of logging and conversion to sugarcane plantations and pastureland. The site continues to be threatened by fires spreading from adjacent plantations, hunting, timber extraction and agriculture (J. M. Goerck in litt. 1999, A. Whittaker in litt. 1999, J. M. Goerck in litt. 2000, SAVE Brasil 2016). The Frei Caneca private reserve and BirdLife/SAVE Brasil area are also still suffering from illegal charcoal exploitation (P. Develey in litt. 2007). The massive clearance of Atlantic forest in Alagoas and Pernambuco has left few other sites likely to support populations of this species. Having a montane distribution that is close to the maximum altitude within its range, this species is also potentially susceptible to climate change (BirdLife International unpubl. data).
Conservation Actions Underway
Considered Critically Endangered at the national level in Brazil (Instituto Chico Mendes de Conservação da Biodiversidade 2018). The efforts of conservationists resulted in the creation of the Murici Ecological Station in 2001, encompassing 6,116 ha. National and international efforts to ensure the effectiveness of this designation are on-going (J. M. Goerck in litt. 1999, 2000). Frei Caneca is a private reserve protecting c. 6 km2 of forest (Mazar Barnett et al. 2005); an additional 360 ha of adjacent forest have been purchased by Birdlife/SAVE Brazil (P. Develey in litt. 2007). Research is ongoing into the species's population size, distribution, demographics, threats and ecology (SAVE Brasil 2016). A species action plan was formulated in 2016 (SAVE Brasil 2016). Actions in the plan include: installation of feeder in Murici, control of nest predators, population monitoring, location of further populations and development of a translocation programme (SAVE Brasil 2016).
Conservation Actions Proposed
Monitor the population at Murici and conduct surveys to confirm the species's status at other sites where it has been recorded. Survey other remnant patches of upland Atlantic forest in Alagoas, Pernambuco and Paraíba to search for further populations. Ensure the de facto protection and management of Murici Ecological Station. Secure the long-term protected status and conservation of Mata do Estado. Implement an environmental education programme at Murici Ecological Station. Conduct research into the species's ecology, associations with mixed-flocks and breeding biology. Consider captive breeding and/or translocating individuals to other, protected areas of Atlantic forest (Lees et al. 2014, Pereira et al. 2014, SAVE Brasil 2016). Restore forest in land adjoining existing forest fragments where the species survives (Pereira et al. 2014).
9.5 cm. Small, uniform antwren. Male entirely grey, slightly paler below with inconspicuous small black patch on throat. Female entirely fulvous-brown above, russet tail. Rufous-buff underparts with white throat. Similar spp. Very similar to Unicoloured Antwren M. unicolor, but not sympatric and has shorter tail and longer bill, and female is more rufescent below. Voice Song is series of 3-6 downslurred, clear-whistled syllables. A kleek contact call and nyiih-nyeeh-nyaah alarm call have been described.
Text account compilers
Pople, R., Taylor, J., Sharpe, C.J., Westrip, J., Ashpole, J, Calvert, R., Wheatley, H., Capper, D., Bird, J., Symes, A., Mahood, S.
Develey, P., Goerck, J.M., Olmos, F., Phalan, B., Roda, S. & Whittaker, A.
BirdLife International (2019) Species factsheet: Myrmotherula snowi. Downloaded from http://www.birdlife.org on 11/12/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 11/12/2019.