Justification of Red List category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 km² combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Population justification
The global population size has not been quantified, but this species is generally described as rare and patchily distributed (Fitzpatrick and de Juana 2020, Marini et al. 2023). It however appears to be locally common, at least in protected areas (Fitzpatrick and de Juana 2020, R. Clay in litt. 2024). Given the frequency of records in the large range (see eBird 2023), the population is unlikely to be small.
Trend justification
The population trend has not been investigated, but declines are suspected based on ongoing conversion and degradation of its grassland habitat (Fitzpatrick and de Juana 2020). The species has been lost from some formerly occupied areas in Bahia state after conversion to agriculture (E.R. Luiz in litt. 2024). However the species has been found in new areas, including protected sites and overall current threats are not sufficient to be driving a rate of reduction that would meet threatened thresholds (Marini et al. 2023). Better monitoring is needed and in parts of the range the rate of habitat loss is suspected to have caused rapid reductions (R. Clay in litt. 2024, E.R. Luiz in litt. 2024).
Culicivora caudacuta occurs locally from north-central Bolivia and central Brazil south to east Paraguay, north-east Argentina and north Uruguay.
It inhabits campo cerrado and open grassland, mainly in dry grassland and occasionally in shorter, scrubbier and wetter areas, and sometimes frequents the transitional zone between these habitats (Lowen et al. 1996, Mitchell et al. 1997, Marini et al. 2023). It is sensitive to disturbance and is rarely found in degraded areas or small fragments of suitable habitat (Fitzpatrick and de Juana 2020, Marini et al. 2023). In parts of the range, the species may be partially migratory (Herzog et al. 2016).
Conversion to soybeans, exportable crops and Eucalyptus plantations (encouraged by government land reform) has severely impacted campo cerrado habitats, with the greatest impact in the southern part of the biome (Parker and Willis 1997). Grasslands within the range are additionally threatened by extensive cattle ranching (Pearman and Abadie 1995, Lowen et al. 1996). Frequent fires to clear land for agriculture is an additional threat (Marini et al. 2023). Measuring the rate of loss of this habitat is more challenging than recording forest loss, and certainly in parts of the range the rate of loss is considered significant (R. Clay in litt. 2024, B. Phalan in litt. 2024).
Conservation Actions Underway
It occurs in several protected areas across its range, including Chapada dos Veadeiros, Emas, Serra de Canastra, Serra do Cipó, Brasília and Nascentes do Rio Parnaíba National Parks (Brazil), as well as Noel Kempff Mercado National Park (Bolivia). It is included in a multi-species action plan for grassland birds in Brazil (ICMBio 2021).
Conservation Actions Proposed
Survey areas of suitable habitat to locate additional populations, obtain population density estimates and quantify the total population size and trend. Study the species' ecology and population structure, and research the migratory behaviour of some populations. Assess the impact of threats and possible reasons for its rarity. Monitor the population trend. Monitor rates of habitat loss.
Expand the area of suitable habitat that has protected status. Restrict monocultures and plantations to already cleared land in order to avoid conversion of pristine cerrado and campos. Remove incentives encouraging habitat loss, especially the planting of Eucalyptus trees on grasslands.
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
Martin, R., Hermes, C.
Contributors
Araujo Guss, C.O., Babarskas, M., Capper, D., Herrera, M., Hesse, C., Lesterhuis, A., Malacco, G., Minns, J., O'Brien, A., Olmos, F., Pople, R., Sharpe, C.J., Symes, A., da Silva, J.M.C., del Castillo, H., Phalan, B., Luiz, É.R., Subirá, R. & Clay, R.P.
Recommended citation
BirdLife International (2024) Species factsheet: Sharp-tailed Tyrant Culicivora caudacuta. Downloaded from
https://datazone.birdlife.org/species/factsheet/sharp-tailed-tyrant-culicivora-caudacuta on 23/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/12/2024.