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.
Large-billed Seed-finch Oryzoborus crassirostris is listed as Least Concern on the basis that it does not approach the thresholds for Vulnerable under any of the IUCN criteria.
The species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence 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). Although the population trend is suspected to be negative, owing primarily to trapping pressure for the cagebird trade (Ridgely and Tudor 1989), the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (at least a 30% decline over ten years or three generations). This species is characterised as uncommon and probably patchily distributed (Stotz et al. 1996); however, the population size has not been quantified and it is 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).
This species was described by Restall et al. (2006) as scarce and localised in most of northern South America, except for Colombia where it is locally fairly common, but very rare in French Guiana and increasingly rare in Guyana and Suriname, where trapping for the cagebird trade is most severe. Recently, it was suggested that this species is still subjected to high trapping pressure for the internal cagebird trade in the Guianas at least (R. Clay in litt. 2010), whilst in Brazil it is described as very uncommon (A. C. De Luca in litt. 2010).
Up-to-date information is requested on this species, in particular the estimated rate of decline over 11 years (estimate of three generations) and the severity of trapping pressure and other potential threats. This species would be eligible for Near Threatened status if undergoing a decline approaching 30% over 11 years, and at least Vulnerable if the rate of decline is 30% or more over 11 years.
Restall, R., Rodner, C. and Lentino, M. (2006) Birds of Northern South America: An Identification Guide. London, UK: Christopher Helm.
Ridgely, R. S. and Tudor, G. (1989) The birds of South America. Austin, Texas: University of Texas Press.
Stotz, D. F., Fitzpatrick, J. W., Parker, T. A. and Moskovits, D. K. (1996) Neotropical birds: ecology and conservation. Chicago: University of Chicago Press.
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