• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Justification of Red List category
This species is listed as Near Threatened because it is presumed to have a small population, which is believed to be declining owing to expansion of the agricultural frontier.

Population justification
The species is likely to be very rare within its range and seems to occur at vanishingly small densities, as suggested by the very low number of records despite intense survey efforts (Costa et al. 2017, 2022; eBird 2022). Even though no quantification of the population density or size has been made, it is suspected that the population numbers less than 10,000 mature individuals, here placed in the band 2,500-9,999 mature individuals.

Trend justification
It is very hard to discern a population trend owing to the paucity of records and the species' tolerance of somewhat disturbed habitats. Nevertheless, the species generally depends on forest cover, but vast areas of forest are currently being cleared for agricultural developments, particularly in the south of the range (Global Forest Watch 2022); it is consequently feared to be decreasing.
Over the past three generations (10.4 years) 8% of tree cover has been lost within the range; since 2017 this has been accelerating to a rate equivalent to 10% over three generations (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). Despite the species' tolerance of secondary growth it is precautionarily assumed that population declines are roughly equivalent to the rate of tree cover loss, and therefore they are here placed in the band 1-19% over three generations.

Clytoctantes atrogularis is endemic to Amazonian Brazil, where it occurs in the Madeira-Tapajós interfluvium in Amazonas, Mato Grosso and Rondônia. Its range is apparently delimited by the Madeira river in the west, and the Sucunduri and Tapajós rivers in the east.

The species occurs in the understory of terra firme forest dominated by dense vine-tangles or understory palms (Costa et al. 2022). It can also be found near treefall gaps, small streams, and sparse stands of Guadua bamboo, sometimes also in somewhat disturbed forest near selectively logged and converted habitats (Costa et al. 2017, 2022; F. Schunck in litt. 2022). It is insectivorous, feeding mainly on ants (Costa et al. 2022).

The principal threats are the expansion of the agricultural frontier as a direct result of highway construction, which has declined in the 1990s, and commercial logging and conversion for industrial agriculture, which are increasing significantly (Cleary 1991, M. Cohn-Haft in litt. 1999). Although its range includes adjacent parts of Amazonas and Mato Grosso, deforestation in Rondônia proceeds apace (Skole and Tucker 1993, Global Forest Watch 2022).
The region of the type locality is by now largely deforested and a hydroelectric dam has been constructed, and other hydroelectric schemes in along the Madeira are proceeding (F. Olmos in litt. 2005, Whitney 2005, Costa et al. 2022).

Conservation Actions Underway
The vicinity of type-locality has been extensively surveyed but the incredible paucity of information makes effective conservation action difficult. The state government of Amazonas, Brazil, as part of its Programa Zona Franca Verde, has created a mosaic of nine conservation areas protecting c. 3,070,000 ha of mostly forested land in the south of the state, including the important Madeira/Tapajós interfluvium (Whitney 2005).

Conservation Actions Proposed
Survey for the species elsewhere in Rondônia, Mato Grosso and Amazonas. Urgently quantify the population size and trend. Investigate its ecology, behaviour and population structure. Quantify the impact of threats, particularly of extensive forest loss, on the population size. Monitor the population trend. Monitor rates of habitat loss.
Establish reserves in areas of undisturbed habitat to protect this and other threatened species. Eliminate incentives for cattle-ranching and other inappropriate forms of agriculture within the region.

17 cm. Plain antbird with striking upturned bill. Huge bill, laterally compressed with lower mandible upturned. Male black. Female rufous-chestnut with black pectoral shield. Similar spp. Black Bushbird Neoctantes niger is slightly smaller (16 cm) with less heavy bill. Voice Loud, trilled whistle tree-tree-tree.

Text account compilers
Hermes, C.

Contributors
Bird, J., Butchart, S., Buzzetti, D., Cohn-Haft, M., Lees, A., Mahood, S., Olmos, F., Phalan, B., Pople, R., Schunck, F., Sharpe, C.J., Silveira, L.F., Subirá, R., Whitney, B. & Williams, R.

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Recommended citation
BirdLife International (2024) Species factsheet: Rondonia Bushbird Clytoctantes atrogularis. Downloaded from https://datazone.birdlife.org/species/factsheet/rondonia-bushbird-clytoctantes-atrogularis 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.