This discussion was first published as part of the 2016 Red List update. At the time a decision regarding its status was pended, but to enable potential reassessment of this species as part of the 2017 Red List update this post remained open and the date of posting was updated.
Great-billed Seed-finch is found on the Pacific slope of south America in southern and eastern Brazil and along the northernmost coast of Brazil into French Guiana north to eastern Venezuela. It is found in one locality in northern Bolivia. The species is listed as Vulnerable under A2cd+3cd+4cd. It is suspected to be undergoing a rapid population decline, as it has become rare in many parts of its range and is known to suffer high levels of persecution for the cage-bird trade, as well as habitat loss and degradation. The global population size has not been quantified but the species is described as ‘uncommon and patchily distributed (Stotz et al. 1996).
The principal threat to the species is the depletion of local populations by cage-bird trappers (Ridgely and Tudor 1989, Olmos 1993, Stotz et al. 1996, Jaramillo and Sharpe 2016), and this activity has caused it to vanish from most of its former range in Brazil. In fact, several long-term Brazilian ornithologists have failed to find this species in the wild since c. 2002, and its remaining wild population must be very small. Habitat loss and degradation, as a result of conversion to agriculture and plantations, is also likely to contribute to declines.
In the Brazilian Red List assessment for birds (MMA 2014) this species is listed as Critically Endangered under C2a(i). The population is estimated at <250 mature individuals with each subpopulation consisting of <50 mature individuals. S. m. magnirostris is found in western Guyana, eastern Venezuela and very marginally in northern Brazil. S. m. maximiliani is found in central and eastern Brazil. Recent records of the subspecies are rare with records limited to just five locations in the states of Goiás, Bahia, Mato Grosso and Mato Grosso do Sul. The species’s assessment on the Brazilian Red List can be accessed here.
Up-to-date information is requested on the species’s population size and trend particularly in countries outside its Brazilian range: French Guiana, Suriname, Guyana and Venezuela. Are levels of trapping for the cagebird trade as significant in the rest of the species’s range as they are in Brazil? Is the population size reduction likely to be >50% in 11 years (three generations)? And is the population undergoing a continuing decline? Considering the Brazilian population is estimated at <250 mature individuals would it be feasible to assume that the global population is <2,500 mature individuals?
Should the population size reduction be >50% over 10 years or three generations owing to habitat loss and trapping for the cagebird trade the species would likely qualify for Endangered globally under A2cd+3cd+4cd. If the global population is estimated at <2,500 mature individuals and it is experiencing a continuing decline with <250 mature individuals in each subpopulation it would likely qualify the species for Endangered under C2a(i).
We welcome comments on the proposed uplisting and any new information on the species.
Jaramillo, A. & Sharpe, C.J. (2016). Great-billed Seed-finch (Oryzoborus maximiliani). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
MMA (2014) Lista Nacional Oficial de Espécies da Fauna Ameaçadas de Extinção. Portaria No 444, de 17 de dezembro de 2014. Diário Oficial da União – Seção 1. Nº 245, quinta-feira, 18 de dezembro de 2014.
Olmos, F. 1993. Birds of Serra da Capivara National Park in the “caatinga” of north-eastern Brazil. Bird Conservation International 3: 21-36.
Ridgely, R. S.; Tudor, G. 1989. The birds of South America. University of Texas Press, Austin, Texas.
Stotz, D. F.; Fitzpatrick, J. W.; Parker, T. A.; Moskovits, D. K. 1996. Neotropical birds: ecology and conservation. University of Chicago Press, Chicago.