This discussion was first published as part of the 2012 Red List update, but remains open for comment to enable reassessment in 2013.
Pale-billed Antpitta Grallaria carrikeri is endemic to the eastern slope of the central Andes in northern Peru, where it is found in montane forest (Ridgely and Tudor 1989). It is currently listed as being of Least Concern, as it was not thought to approach the thresholds for Vulnerable under any of the IUCN criteria.
Although this species has a restricted range, it was not believed to approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence [EOO] of less than 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). The population trend appeared to be stable, and hence the species was not thought to approach the thresholds for Vulnerable under the population trend criterion (at least a 30% decline over ten years or three generations). The population size has not been quantified, but was not believed to approach the thresholds for Vulnerable under the population size criterion (fewer than 10,000 mature individuals with a continuing decline estimated to be at least 10% over ten years or three generations, or with a specified population structure).
A recent improvement of the species’s range map has resulted in a revised EOO estimate of c.7,200 km2. This meets the range size threshold for Vulnerable under criterion B1. However, there is uncertainty over the severity of habitat fragmentation in its range (the proportion of habitat in patches too small to support viable populations and separated by distances several times larger than the species’s average long-term dispersal distance) and the number of locations it is known from. Deforestation has been widespread in the northern central Andes of Peru, although most of it has been concentrated below the species’s elevation range (Garcia-Moreno et al. 1997). Forest clearance in the region largely takes place through timber extraction, clearance for agriculture, including the cultivation of cash-crops, and to secure land ownership (Barnes et al. 1995, Davies et al. 1997, J. Hornbuckle in litt. 1998, Kessler and Herzog 1998). Forest clearance has been particularly rapid on the Cordillera de Colán since the late 1970s (Barnes et al. 1995, Kessler and Herzog 1998), where local people have estimated that all remaining forest could be lost in the next decade. Some areas of cloudforest in its range may be impacted by the widespread practice of burning páramo to maintain pastureland (e.g. Kessler and Herzog 1998).
The species’s population size has apparently not been quantified; however, given its small range, it might be expected to have a small population and may qualify for a higher category under criterion C2, although information on its subpopulation structure would also be required for a listing higher than Near Threatened.
It is suggested that this species qualifies for uplisting at least to Near Threatened under criterion B1a+b(ii,iii) on the basis that it has a small range, in which there are on-going declines in the Area of Occupancy and area, extent and/or quality of habitat owing to continued deforestation. Comments are invited on this suggested category change, as well as on the potential for the species to qualify as Vulnerable under B1. Further information is also requested, including the number of locations from which the species is known, the percentage of habitat that exists in isolated patches too small to support viable populations, and the likely population size, number of subpopulations and proportion of the total population that forms the largest subpopulation.
Barnes, R., Butchart, S., Clay, R., Davies, C. and Seddon, N. (1995) The conservation status of the Cordillera de Colán, northern Peru. Cotinga 3: 6-7.
Davies, C. W. N., Barnes, R., Butchart, S. H. M., Fernandez, M. and Seddon, N. (1997) The conservation status of birds on the Cordillera de Colán, Peru. Bird Conserv. Int. 7: 181- 195.
García-Moreno, M. J., Tibosch, J. H. and Ballón, G. (1997) Estado de conservación de la avifauna de la Cordillera Colán, Departamento de Amazonas, Perú. Informe de Campo.
Kessler, M. and Herzog, S. K. (1998) Conservation status in Bolivia of timberline habitats, elfin forest and their birds. Cotinga 10: 50-54.
Ridgely, R. S. and Tudor, G. (1989) The birds of South America. Austin, Texas: University of Texas Press.
- Archived 2011-2012 topics: Watkins’s Antpitta (Grallaria watkinsi): uplist to Near Threatened?
- Archived 2010-2011 topics: Elusive Antpitta (Grallaria eludens): downlist to Least Concern?
- Archived 2010-2011 topics: Cundinamarca Antpitta (Grallaria kaestneri): uplist to Endangered?
- Archived 2011-2012 topics: Brown-banded Antpitta (Grallaria milleri): downlist to Vulnerable?
- Archived 2010-2011 topics: Antioquia Antpitta (Grallaria fenwickorum): newly described, and Critically Endangered?