Archived 2011-2012 topics: Blue-and-gold Tanager (Bangsia arcaei): request for information

This discussion was first published on Dec 2 2010 as part of the 2010-2011 Red List update.

Initial deadline for comments: 31 January 2012.

Link to BirdLife species factsheet for Blue-and-gold Tanager

Blue-and-gold Tanager Bangsia arcaei is currently listed as Near Threatened under criteria A2c; A3c; A4c; B1a+b(i,ii,iii,iv,v) because, although its Extent of Occurrence (EOO) is less than 20,000 km2 and declines are suspected in its range owing to habitat clearance and degradation, and its population is suspected to be experiencing a moderately rapid decline owing to the same threats, the population, however, is not yet considered to be severely fragmented or restricted to a few locations.

The latest population estimate for this species in Costa Rican Important Bird Areas of 2,500-3,900 mature individuals (Sánchez et al. 2009) suggests that the total population could number fewer than 10,000 mature individuals, potentially making the species eligible for uplisting to Vulnerable under criteria C1 and C2. However, to qualify the species must be shown to be experiencing a continuing decline of at least 10% over 11 years (estimate of three generations), or at least have a population decline inferred, combined with the knowledge that all mature individuals are in one sub-population (or that all sub-populations number no more than 1,000 individuals).

Up-to-date information is requested on this species’s likely total population size, population trend and threats. Particular detail is requested on the level of habitat fragmentation within its range, i.e. the percentage of suitable habitat in patches too small to support viable populations.

Sánchez, J. E., Criado, J., Sánchez, C. and Sandoval, L. (2009) Costa Rica. In Devenish, C., Díaz Fernández, D. F., Clay, R. P., Davidson, I. J. and Yépez Zabala, I. eds. Important Bird Areas Americas – Priority sites for biodiversity conservation. Quito, Ecuador: BirdLife International (BirdLife Conservation Series No. 16).

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3 Responses to Archived 2011-2012 topics: Blue-and-gold Tanager (Bangsia arcaei): request for information

  1. esta especie fue registrada en la Serranía del Darién, sector de colombia, observaciones de Juan Miguel Ruiz

  2. In the past 10 years, severe deforestation has been taking place within perhaps half of the species’ range in Panama. Deforestation is particularly severe along the approximately 100 km of the cordillera within the Comarca Ngobe-Bugle (formerly eastern Bocas del Toro). Deforestation has now reached the continental divide in some areas (personal observation). Because of its narrow altitudinal range, this species is also very likely to be vulnerable to climate change.

    Given that Panama probably constitutes half or more of the species’ total range, current deforestation likely constitutes more than 10% of the species global range. Uplisting of this species to Vulnerable is warranted.

  3. The species is distributed from the Cordillera de Guanacaste south along the Caribbean Slope of the Cordilleras of Tilarán, Volcánica Central and Talamanca. The habitat availability in Cordillera de Guanacaste is small and the species is scarce here. Along the Cordilleras of Tilarán and Volcánica Central it is a locally common to uncommon species. While in Talamanca, is locally common along the Rio Reventazón drainage.

    This species inhabits middle elevations between 400- 1200m, but most observations occur between 600-1000m. This distribution belt in Costa Rica is fairly well protected throughout the country, including several National Parks, and Protected Zones. These protected areas which include almost the whole distribution of the species hasn’t suffered habitat destruction for at least the last three decades, and historically the forest has not being much cleared in these areas. Hence, we do not consider that the species has suffered any kind of population decline during the last years. Our position is not different from that of Sánchez et al (2009). While the populations are thought to be under the 10000 individuals, we do not believe that the populations are under any direct threat as to consider an uplisting to Vulnerable. Further, there have not been any decreases in the population sizes, which we consider to be between 2,500-3,900 mature individuals, nor we expect this to occur in the near future, mainly because most its habitat is protected under different conservation categories by the Costa Rican state as mentioned before.

    Future research in this species should consider an estimation of the size of its populations. While in the north the suitable habitat is small, hence there is a small population, the southernmost areas, (south between the Rio Reventazón and the Panama border) have good suitable habitat, but are of hard access so little ornithological research has being conducted here.

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