Data Zone
Justification of Red List category
This species has a very 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 uncommon or rare (Stotz et al. 1996, Herzog et al. 2016, Freile and Restall 2018). It is however easily overlooked (Schulenberg 2020) and may therefore be more numerous and widespread than assumed.
Trend justification
The only threat known to the species is the logging and fragmentation of forests within the range. On the basis of ongoing habitat loss, population declines are suspected.
The population trend has not been quantified. Tree cover within the range is lost at a rate of 5% over ten years (Global Forest Watch 2023, using Hansen et al. [2013] data and methods disclosed therein). Even though the species depends on forests, its preference for edge habitat suggests some tolerance of forest loss. Population declines are therefore likely slow; they are here tentatively placed in the band 1-9% over ten years.
Zimmerius cinereicapilla has a scattered distribution in the east Andean foothills from northern Ecuador through Peru to northwest Bolivia (Schulenberg et al. 2010, Herzog et al. 2016, Freile and Restall 2018). A continuing decline in the area and quality of the species' habitat is estimated from the 5% loss of forest cover within the mapped range over the past ten years (Global Forest Watch 2023, using data from Hansen et al. [2013] and methods disclosed therein).
This is a species of humid montane and foothill forest, where it generally remains in the canopy. It prefers edges and openings, but also occurs in forest interior. Insects constitute the bulk of its diet, but it also feeds on fruits including those of the mistletoes (Loranthaceae) (del Hoyo et al. 2004).
The primary threat to this species stems from deforestation, with parts of its range under pressure from logging, mining, agriculture and road building (del Hoyo et al. 2004, Schulenberg 2020, Global Forest Watch 2023).
Conservation Actions Underway
No targeted actions are known for this species.
Conservation Actions Proposed
Quantify the population size. Research the species' ecology and population structure. Research its tolerance of habitat loss and degradation. Monitor the population trend.
Expand the protected area network to effectively protect key sites. Effectively manage protected areas, utilising emerging opportunities to finance protected area management with the joint aims of reducing carbon emissions and maximizing biodiversity conservation. Incentivise conservation on private lands through expanding market pressures for sound land management and preventing forest clearance on lands unsuitable for agriculture (Soares-Filho et al. 2006).
10-11 cm. Large-headed green-and-yellow tyrannulet. Dark olive upperparts. Breast is a paler olive colour, fading into yellow on the belly. Grey forehead, crown and lores. Voice An ascending series, beginning with an emphatic note and ending with a wheet-wheet?.
Text account compilers
Hermes, C.
Contributors
Butchart, S., Ekstrom, J., Khwaja, N., Symes, A. & Sharpe, C.J.
Recommended citation
BirdLife International (2024) Species factsheet: Red-billed Tyrannulet Zimmerius cinereicapilla. Downloaded from
https://datazone.birdlife.org/species/factsheet/red-billed-tyrannulet-zimmerius-cinereicapilla on 22/11/2024.
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 22/11/2024.