Justification of Red List Category
This species qualifies as Vulnerable because it appears to be undergoing a rapid decline owing to continuing habitat degradation and destruction.
Although this species is rare and localised, it has a very large range, and numbers are likely to exceed 10,000 mature individuals. It is thus placed in the band 10,000-19,999 mature individuals, which equates to 15,000-29,999 individuals in total, rounded here to 15,000-30,000 individuals.
This species is suspected to be declining rapidly, in line with rates habitat loss within its range.
Culicivora caudacuta occurs in east Bolivia (Beni, La Paz, Santa Cruz), extreme north and south-central Brazil (Amapá, south-west Bahia, south Mato Grosso, Mato Grosso do Sul, central Goiás, Distrito Federal, Minas Gerais, west Paraná, São Paulo), east and south-west Paraguay and north-east Argentina (east Formosa, east Chaco, Corrientes, north Santa Fe, Entre Ríos, south Misiones) (Armonía 1995; Canevari et al. 1991; Hayes 1995; Ridgely and Tudor 1994; Sick 1993; J. M. C. da Silva in litt. 1999; Souza 1999). In Brazil it is found mostly in the upland cerrado of the Planalto Central, Central, a more restricted distribution compared to other cerrado birds. It is now mostly rare and very localised but there are recent range extensions from Entre Ríos (Pearman and Abadie 1995) and La Paz (Parker et al. 1991) and it continues to be observed frequently at known locations in Paraguay.
It inhabits campo cerrado and open grassland, mainly in dry grassland and occasionally in shorter, scrubbier and wetter areas (Lowen et al. 1996), and sometimes frequents the transitional zone between these habitats (D. R. Capper et al. in litt. 2000; Mitchell et al. 1997). However, breeders (October-March) are apparently confined to dry grassland (Clay et al. 1998; Lowen et al. 1996), with nests in Formosa mostly located in clumps of Vernonia chamaedrys (Di Giácomo 1996).
Conversion to soybeans, exportable crops and Eucalyptus plantations (encouraged by government land reform) has severely impacted campo cerrado habitats (Parker and Willis 1997), with the greatest impact is in the southern part of the biome. Grasslands in south Paraguay and Argentina are additionally threatened by extensive cattle ranching (Lowen et al. 1996; Pearman and Abadie 1995). Observations from Canindeyú department, Paraguay (towards the edge of the species's range), demonstrated an apparent preference for older campo cerrado habitats that had not experienced a spring burn and where Loudetia grass species sprout up to c. 2 m tall during the summer months. This taller vegetation does not occur under an annual (or more frequent) burn regime, as occurs at many cerrado localities (R. Pople in litt. 2003). This lack of availability of preferred habitat along with the frequent occurrence of fires is a possible threat.
Conservation Actions Underway
It is protected by Paraguayan law where it is considered Vulnerable on a national level. Guyra Paraguay and Entidad Binacional Yacyreta are currently studying threatened grassland species at Reserva Isla Yacyreta and other IBAs in the south of the country (H. del Castillo in litt. 2012).
11 cm. Small brownish tyrant. Well-marked head with crown black, supercilium white and eyestripe black. Upperparts dark brown, heavily streaked with buff. Brown tail feathers long, slender and pointed. Underparts white with cinnamon flanks. Voice Thin interrogative ree?.....ree?.....
Text account compilers
Capper, D., Sharpe, C J, O'Brien, A., Symes, A., Babarskas, M.
Pople, R., Hesse, C., Malacco, G., da Silva, J., del Castillo, H., Capper, D., Araujo Guss, C.O., Herrera, M., Minns, J., Lesterhuis, A., Olmos, F.
BirdLife International (2018) Species factsheet: Culicivora caudacuta. Downloaded from http://www.birdlife.org on 18/02/2018. Recommended citation for factsheets for more than one species: BirdLife International (2018) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 18/02/2018.