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

Justification of Red List category
This species has a 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). Although suspected of declining very slowly, it does not meet or approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is large, and hence does not 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 population size of this species has not previously been estimated. Although poorly known, at some sites it has proven to be relatively common, including in degraded habitats (Beehler and Pratt 2016, eBird 2022).
Within this species' mapped range there was c.25,000 km² of forest in 2021 (Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein). In one study, a male ranged over approximately 15 ha over seven days of observation (Beehler and Beehler 1986); approximating this to a territory size and assuming only a small portion (10-30%) of forest in the mapped range is occupied, the population is likely to be fairly large, at 30,000-90,000, rounded here to 25,000-99,999 mature individuals.

Trend justification
The population is suspected to be slowly declining. Forest loss in this species' mapped range equated to 2-3% in the three generations (c.15 years; Bird et al. 2020) to 2021 (Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein). Although tolerant of some selective logging (Beehler and Pratt 2016), such losses are suspected of causing a very slow decline in the number of mature individuals.

Drepanornis bruijnii is a poorly known species which ranges along the north New Guinea coast from the south-east coast of Geelvink Bay, West Papua (formerly Irian Jaya), Indonesia, east to Vanimo, just across the border into Papua New Guinea (Beehler and Pratt 2016). It is widespread and usually fairly common within this fairly small range, with one male ranging over 15 ha in a week-long study.

It is relatively common in selectively logged forest; most records are from the lowlands below 180 m (Whitney 1987, Frith and Beehler 1998, Beehler and Pratt 2016). Joins flocks of mixed species: with pitohuis, babblers, other rufous birds. Males have large territories and display on branches in midstory trees (Pratt and Beehler 2015).

Lowland forests throughout its range are under pressure from timber extraction and development schemes (N. Bostock in litt. 1994, Sujatnika et al. 1995), though it has been said that only minor deforestation has been seen in the region in the last 50 years and logged areas can return to closed forest fairly rapidly (B. Beehler in litt. 2016). 

 

Conservation Actions Underway
CITES Appendix II.

Conservation Actions Proposed
Regularly monitor the populations at selected sites. Further research its tolerance of degraded forest. Protect significant areas of remaining primary forest within its range.

Text account compilers
Berryman, A.

Contributors
Bostock, N. & Beehler, B.M.

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Recommended citation
BirdLife International (2024) Species factsheet: Pale-billed Sicklebill Drepanornis bruijnii. Downloaded from https://datazone.birdlife.org/species/factsheet/pale-billed-sicklebill-drepanornis-bruijnii on 23/11/2024.
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 23/11/2024.