VU
Yellow-green Tanager Bangsia flavovirens



Justification

Justification of Red List category
This species has a small range, within which it is known from only few locations. Habitat loss is occurring at a significant rate, and hence its range and population are likely to be declining (Collar et al. 1992). The total population is assumed to be small and subpopulations to be very small. These factors result in its classification as Vulnerable.

Population justification
The population is estimated to number 2,500-9,999 mature individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size, and the fact that only a proportion of the estimated Extent of Occurrence is likely to be occupied. This estimate is equivalent to 3,750-14,999 individuals in total, rounded here to 3,500-15,000 individuals.

Trend justification
A slow to moderate and on-going population decline is suspected, based on rates of habitat loss within the species's range.

Distribution and population

Bangsia flavovirens occurs on the lower Pacific slopes of the Andes in north-west Ecuador (Esmeraldas and Pichincha) and south-west Colombia (Nariño and Valle del Cauca [Hilty 1977]). rare and local in Ecuador (Athanas and Greenfield 2016). In Esmeraldas, it is known from El Placer, Awacachi Corridor (Krabbe and Nilsson 2003), Alto Tambo (B. Palacios verbally 2006), Cotacachi-Cayapas Ecological Reserve (O. Jahn in litt. 2007, Jahn et al. in press), and the Canandé Reserve (F. Sornoza Molina verbally 2006). In Pichincha, it occurs along the Milpe road (Krabbe and Nilsson 2003). In Colombia, there is a cluster of four sites in Nariño and two sites in Valle del Cauca (also close to each other), and there are large areas of mostly intact habitat between these two areas (R. Strewe in litt. 1999, P. G. W. Salaman in litt. 1999, 2000). It is fairly common to common at a few localities (P. G. W. Salaman in litt. 1999, 2000).

Ecology

It inhabits wet mossy forest, forest edge and tall trees in clearings at 450-1,100 m. It usually occurs in pairs or groups of 3-6 individuals, often associated with mixed-species flocks, mostly at midstorey and subcanopy levels. Nests have been found in March and April, and nest-building has been recorded in August. Its diet consists primarily of fruit, but also includes flowers and insects (Renjifo et al. 2002).

Threats

The Chocó region has long been a source of timber, but logging has intensified since the mid-1970s (WWF and IUCN 1994-1997). Infrastructural development, particularly the rapid expansion of the road network, in the region is increasing the extent of logging, small-scale agriculture and gold mining (Salaman 1994, Wege and Long 1995, Salaman and Stiles 1996, WWF and IUCN 1994-1997). There is intensive agricultural development, especially coca and banana plantations at lower altitudes, cattle-farming (Salaman 1994, WWF and IUCN 1994-1997, Bowen-Jones et al. 1999). Large-scale deforestation for  timber and subsequent commercial oil palm cultivation was a major threat, at least in 1990s (Sharpe 1999). New legislation and the transfer of land-rights to local communities has been exploited by large businesses, for whom it has become cheap and easy to buy land (Bowen-Jones et al. 1999, P. G. W. Salaman in litt. 1999, 2000). International investment in the region has been lacking in concern for the environment (P. G. W. Salaman in litt. 1999, 2000). Overall, the rate of deforestation is high and increasing, particularly in Ecuador, Nariño, and along new roads, with forest degradation compounding the situation (Salaman 1994, Salaman and Stiles 1996, P. G. W. Salaman in litt. 1999, 2000). By 1996, the remnant cover of evergreen premontane forest (300-1300m) in western Ecuador was only 40% (Sierra 1999). In Esmeraldas, the cover of this forest type was reduced by 7% in the last decade (Cárdenas 2007). The Cotacachi-Cayapas Ecological Reserve, Esmeraldas, is threatened by incursions from local communities and colonists from Colombia and other regions of Ecuador (O. Jahn in litt. 2007). Forests around Alto Tambo are largely unprotected and threatened by clearance for cattle ranching and forestry projects (O. Jahn in litt. 2007).

Conservation actions

Conservation Actions Underway
It occurs in the Farallones de Cali National Park and El Pangan Nature Reserve, Colombia (P. G. W. Salaman in litt. 1999, 2000, R. Strewe in litt. 1999, Renjifo et al. 2002). In Ecuador, it is present in the Awacachi Corridor (Krabbe and Nilsson 2003), Cotacachi-Cayapas Ecological Reserve (Jahn et al. in press, O. Jahn in litt. 2007), Canandé Reserve (F. Sornoza Molina verbally 2006), and at least close to the Milpe Reserve (Krabbe and Nilsson 2003).

Conservation Actions Proposed
Survey Pacific foothill-forests (P. G. W. Salaman in litt. 1999, 2000), especially between the three known areas of occurrence, and in unstudied parts of Los Farallones de Cali (Wege and Long 1995). Designate protected areas in the Pacific foothills (P. G. W. Salaman in litt. 1999, 2000). Consolidate protection of the Awacachi Biological Corridor to maintain link between Awá Ethnic Reserve and Cotacachi-Cayapas Ecological Reserve and the surrounding buffer zone (O. Jahn in litt. 2007). Sustainably manage the buffer zone to the Awá Ethnic Reserve and Cotacachi-Cayapas Ecological Reserve (O. Jahn in litt. 2007). Consolidate protection of the Cotacachi-Cayapas Ecological Reserve through law enforcement against illegal logging, hunting, and colonization inside the reserves and sustainable management projects in its buffer zone (O. Jahn in litt. 2007).

Identification

14.5 cm. Easily overlooked dull olive tanager. Olive above, olive-yellow below, yellower on throat, median breast and undertail. Brownish iris. Similar spp. Yellow-throated Bush-tanager C. flavigularis (which typically forages in lower forest strata) has greyish underparts contrasting with yellow throat and white irides. Voice Hoarse, rasping rasping chut and chip-chut or chut-chip notes repeated frequently (Krabbe and Nilsson 2003, Jahn et al. in press).

Acknowledgements

Text account compilers
Bird, J., Isherwood, I., Jahn, O., Pople, R., Sharpe, C J, Stuart, T. & Symes, A.

Contributors
Jahn, O., Salaman, P., Sornoza Molina, F. & Strewe, R.


Recommended citation
BirdLife International (2024) Species factsheet: Yellow-green Tanager Bangsia flavovirens. Downloaded from https://datazone.birdlife.org/species/factsheet/yellow-green-tanager-bangsia-flavovirens 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.