Data Zone
Justification of Red List category
This species occurs at very low population densities and is often absent even in seemingly appropriate habitat. Overall it is considered to have a small population that is isolated in small subpopulations. In much of its range, habitat loss and degradation are proceeding, indicating that there are significant and ongoing declines in range and population. This combination of factors has led to its listing as Vulnerable.
Population justification
Based on reported population sizes for Ecuador and Colombia, the global population size is estimated to be between 2,500-12,000 mature individuals. The species occurs at low densities and is dependent on undisturbed forest (BirdLife International 2000, Karubian and Carrasco 2008, Erritzøe et al. 2012): it is naturally rare and very challenging to detect (Hughes 2020, E. Montenegro in litt. 2023). A study carried out in 2018-2019 in Esmeraldas (Ecuador), involving 120 days of monitoring along transects using playback and visual surveys, only recorded three individuals, with a further three individuals photographed in camera traps outside of the transects (Montenegro 2020, E. Montenegro in litt. 2023). Studies at Bilsa Biological Station, within the Mache-Chindul Ecological Reserve in Ecuador, derived an estimate of 40 pairs based on the home range size from a single tracked individual of 50 ha extrapolated across approximately 2,000 hectares of suitable habitat within the 3,500 ha reserve, or a density of 4 mature individuals per square kilometre (Karubian and Carrasco 2008). But this approach, scaling up from one observed home range is considered likely to overestimate density. An extensive investigation of the bird community in Esmeraldas province between 1997 and 2006 recorded very few records and did not report a density (Jahn 2011), however an extremely low value of 0.125-0.25 individuals/km2 was given subsequently (O. Jahn in litt. 2008): although the data used for this value is unclear (cf. Jahn 2011) and given the extremely low detectability may be expected to underestimate true occurrence. Densities of the closely related N. geoffroyi have been estimated at 2 mature individuals/km2 in Panama (Robinson et al. 2000) and 0.5 mature individuals/km2 in Peru (Terborgh et al. 1990).
The national population in Ecuador has been placed in the band 250-2,499 mature individuals, with no subpopulation deemed larger than 250 mature individuals (Freile et al. 2019). The Colombian population was estimated at 2,372 mature individuals using 0.5 mature individuals/km2, extrapolated across an estimated suitable and likely occupied habitat area of 4,745 km2 (Renjifo et al. 2014). This habitat value is already restricted from the estimated area of remaining habitat given as 7,427 km2 (Renjifo et al. 2014). Despite the suggestion that this may very well be an overestimate (Renjifo et al. 2014) it uses the lowest density for the genus applied to a restricted potential area of habitat and hence seems a reasonable approximation for the population size in the country. Using the density based on the home range of this species gives an estimate of 18,980 mature individuals, obviously using 2 individuals/km2 (per N. geoffroyi in Panama) halves this to 9,490 mature individuals. With concerns over the home range size overestimating density for this very rarely detected species, a reasonable but moderately precautionary range for the population size in Colombia is 2,350-9,490 mature individuals. An important observation is that recent records have continued to extend the distribution beyond that recognised in Renjifo et al. (2014) as far as Antioquia (Munera 2014, eBird 2024), suggesting that the area of suitable forest habitat is an underestimate.
Trend justification
The population trend has not been quantified directly. However, the species is feared to be in declines due to its strict dependence on the interior large and undisturbed primary forests and ongoing logging and forest degradation within the range (Renjifo et al. 2014, Hughes 2020, Global Forest Watch 2023). Secondary forests comprise only 25% of the individuals' home ranges (Hughes 2020); therefore the species will be disproportionally affected by the loss of primary forests as it restricts the number of territories and consequently of mature individuals that can be sustained.
Very rapid habitat loss took place within the southern portion of the range of the species in the second half of the 20th century (Dodson and Gentry 1991). Tree cover within the range is lost at a rate of 3% over three generations (19.9 years; Global Forest Watch 2023, using Hansen et al. [2013] data and methods disclosed therein). This value however does not account for disturbance and conversion of primary forests into secondary, degraded forests, nor for the impacts of forest fragmentation and increasing distance between subpopulations. Consequently, the total rate of habitat loss may be substantially higher than 3% over three generations. It is here tentatively placed in the band 10-19% over three generations, and population declines are assumed to be roughly equivalent (see also Freile et al. 2019).
Neomorphus radiolosus is found on the Pacific slope of the West Andes in west Colombia to north-west Ecuador. Despite vast tracts of continuous forests remaining within the range, it appears absent from large areas of seemingly suitable habitat, and records are scarce and localised (eBird 2023). In Colombia most records were previously restricted to the southern part of the Chocó (Hilty and Brown 1986, Ayerbe-Quiñones et al. 2008, Calderón-Leyton et al. 2011, Erritzøe et al. 2012) but extended considerably northwards by López-Ordóñez et al. (2013) and further to the Área de Manejo Especial Étnico del Alto Amurrupá in Risarelda Department (Martínez-Gómez et al. 2013). Additionally there is photographic evidence of the occurrence in Reserva la Bonga, more than 150 km further north in Antioquia (Munera 2014). Consequently the extent of occurrence is estimated at a larger value than in previous assessments, at 138,000 km2.
Extensive and rapid deforestation in the Ecuadorian and southern Colombian portion of the range in the second half of the 20th century (Dodson and Gentry 1991) reduced the area of occupancy and by inference the population size. This decline is continuing but at a much reduced rate but remaining forest in these areas is fragmented and degraded. Consequently continuing declines in the area of occupancy and in the area, extent and quality of habitat are inferred.
It inhabits wet foothill and lower montane forests with most records between 400-1,500 m (Martínez-Gómez et al. 2013, Hughes 2020) but with records below 100 m and up to 1,695 m (del Hoyo et al. 2014, Huang et al. 2021, eBird 2023). It seems to be dependent on the interior of continuous primary forest and is only rarely observed in adjacent secondary areas (López-Lanús et al. 1999): a radio-tracked individual avoided secondary forest (Karubian and Carrasco 2008). This individual, tracked while breeding used a home range of 42.2 ha (Minimum Convex Polygon, MCP) or 49.9 ha (95% kernel analysis) (Karubian and Carrasco 2008). Reports and information from local people suggest that it sometimes associates with collared peccaries Tayassu tajacu, and with mixed-species bird flocks attending army ant swarms (Hornbuckle et al. 1997, López-Lanús et al. 1999). However a radio tracked individual was rarely associated with army ants (9.5% of location fixes) and never with mammals, though the latter may have been due to their low abundance at the study site (Karubian and Carrasco 2008). It forages for arthropods from the ground by scouring foliage, stems and tree-trunks, or catching prey disturbed by army ants or by itself (Hornbuckle et al. 1997, López-Lanús et al. 1999, Karubian and Carrasco 2008). Two recently documented nesting attempts provided the first information on its nesting biology: one took place in March-April and the other in May, and both nests were located c.5 m above ground in understorey trees in primary forest (Karubian et al. 2007). The clutch size appears to be small and may be only a single egg (Karubian et al. 2007). A wide range of invertebrates (particularly grasshoppers) and vertebrates (mainly small frogs) were fed to the nestling (Karubian et al. 2007).
The most severe threat to the species is the logging of its forest habitat for large-scale timber extraction activities and the creation of oil palm plantations, with additional loss and degradation of habitat through small-scale agriculture and cattle ranching, gold mining and roadbuilding (Salaman 1994, WWF/IUCN 1994-1997, Wege and Long 1995, Salaman and Stiles 1996, Álvarez 2002, Renjifo et al. 2014). Forests below 1,000 m are particularly affected by logging activities; in the Ecuadorian part of the range around 68% of the original lowland forest cover has already disappeared, while c. 50% of forests in higher elevations remain (Finer and Mamani 2019). Most of this loss took place prior to 2000 (Dodson and Gentry 1991).
Conservation Actions Underway
It is known from several protected areas, including Los Farallones de Cali and Munchique National Parks, El Pangan Nature Reserve (Colombia), Cotacachi-Cayapas and Mache-Chindul Ecological Reserves, as well as the private Canandé and Tesoro Escondido Reserves (Ecuador). It is listed as Endangered at the national levels in Colombia and Ecuador (Renjifo et al. 2014, Freile et al. 2019).
46 cm. Terrestrial, forest roadrunner-like cuckoo. Heavy dusky above, and yellow below, its bill. Large bare blue, ocular area. Blackish glossed blue, prominent crest and hindneck. Black back and underparts with buffy-white scaled or banded appearance. Chestnut wings and lower back. Blackish glossed green, long tail. Immature similar; has ochraceous scaling and lacks bluish head sheen. Similar spp. Rufous-vented Ground-cuckoo N. geoffroyi with yellow bill, bronzy-brown above including tail, glossed green wings and narrow, broken, black chest-band. Voice Song repeated deep cow-like or dove-like moo, also loud bill-clapping (Jahn et al. 2002, Krabbe and Nilsson 2003). Hints Follows army ant swarms and groups of large mammals.
Text account compilers
Hermes, C.
Contributors
Benstead, P., Bird, J., Isherwood, I., Jahn, O., Karubian, J., Mena-Valenzuela, P., Mew, J., Montenegro, E., Palacios, B., Salaman, P.G.W., Sharpe, C.J., Solano, A., Stuart, T., Symes, A. & Sánchez-Nivicela, M.
Recommended citation
BirdLife International (2024) Species factsheet: Banded Ground-cuckoo Neomorphus radiolosus. Downloaded from
https://datazone.birdlife.org/species/factsheet/banded-ground-cuckoo-neomorphus-radiolosus 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.