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.
Forbes’s Blackbird is currently known from widely scattered sites in Pernambuco, Alagoas and Minas Gerais, east and north-east Brazil, and has a very small and fragmented range. The population size has been preliminarily estimated to fall into the band 1,000-2,499 individuals, which equates to 667-1,666 mature individuals, with extremely small subpopulations, and overall numbers were estimated to be declining owing to brood-parasitism by the Shiny Cowbird and, to a lesser extent, habitat loss and exploitation for the pet trade. As a result, the species has been listed as Endangered under Criteria B1ab and C2a(i).
In the Brazilian Red List assessment for birds (MMA 2014) the population of A. forbesi has been assessed as up to 10,000 mature individuals, with all subpopulations numbering fewer than 1,000 mature individuals. The species has thus been listed as Vulnerable under criterion C2a(i). The species’s assessment on the Brazilian Red List can be accessed here. In addition, revisions to the method for calculating Extent of Occurrence mean that this is now calculated at 447,000 km2 for the species.
Up-to-date information is requested on the species’s population size, subpopulation structure and level of fragmentation. Confirmation of a population larger than 2,500 mature individuals and/or a subpopulation larger than 1,000 mature individuals and a population that is not severely fragmented would likely qualify the species to be downlisted to Vulnerable under Criterion C2a(i). The species is apparently doing well in forest fragments and adapting to urban areas (B. Hennessey in litt. 2016) – is there a quantified estimate of the current population trend? If the population trend is quantified and found to be in a continuing decline of 10% in three generations and the population is <10,000 mature individuals then the species would also warrant Vulnerable status under C1. Comments on the proposed downlisting are welcome.
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.