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). 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 is considered to be large and 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.
The global population size has not been quantified, but this species is described as 'fairly common' (Stotz et al. 1996). However, based on the low number of observational records (per eBird 2021) within the range, it is assumed that the population may be moderately small; it is here placed in the band 10,000-19,999 mature individuals.
The species is suspected to be undergoing a slow decline due to habitat loss and degradation. Tree cover loss within the species range equated to c. 4% over the past three generations; this rate has further slowed since 2016, equating to c. 2% over three generations ([11.7 years; Bird et al. 2020], Global Forest Watch 2021, using Hansen et al.  data and methods disclosed therein). The species, although forest dependent, does also occur in edge habitats and can be found at secondary forests (Parker et al. 1996, Ridgely and Greenfield 2001, Byington 2020). As such, rates of decline are not thought to exceed 5% over three generations.
Nyctiphrynus rosenbergi occurs in west Colombia (Chocó, Valle del Cauca, Nariño and possibly Cauca) and north-west Ecuador (Esmeraldas, north-west Pichincha and south-west Imbabura) (Ridgely and Greenfield 2001) where it may be relatively common.
It occurs in very humid lowland evergreen forest and edge from almost sea level (GBIF.org 2022), favouring treefalls and river edges, but also in adjacent secondary forest up to 900 m (Parker et al. 1996, Ridgely and Greenfield 2001), locally up to 1,340 m (Huang et al. 2021). The species feeds mainly on insects (Byington 2020).
Unplanned colonisation following the completion of roads, and massive logging concessions have previously cleared or degraded over 40% of its Chocó forests (Salaman 1994). Intensive logging, human settlement, cattle-grazing, mining and coca and palm cultivation are thought to threaten its remaining forest habitat (Dinerstein et al. 1995). Large areas of its western Ecuadorian range have been purchased, denuded of forest and converted to industrial oil palm plantations (Sharpe 1999). However, recent deforestation analysis showed that tree cover loss within the species' range has equated to c. 4% over the past three generations, slowing to a rate of c. 2% since 2016 (Global Forest Watch 2021, using Hansen et al.  data and methods disclosed therein). In Colombia, suitable habitat is also thought to have been lost by 4% during 2000 and 2015, equating to only 3% over the past three generations (Negret et al. 2021). Therefore, current levels of habitat loss are considered to be minimal.
Conservation Actions Underway
None targeted actions are known for this species.
Text account compilers
Benstead, P., Capper, D., Sharpe, C.J. & Symes, A.
BirdLife International (2022) Species factsheet: Nyctiphrynus rosenbergi. Downloaded from http://www.birdlife.org on 01/12/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 01/12/2022.