Azores Bullfinch Pyrrhula murina is confined to the east of the island of São Miguel in the Azores (Portugal). It is currently listed as Endangered under Criteria B1ab(iii)+2ab(iii), as it occurs at only one locality (Pico da Vara/Ribeira do Guilherme Special Protection Area) and has a very small range, within which the quality of its habitat was thought to be decreasing due to the spread of invasive plant species, when it was last assessed in 2011.
Since then, a considerable amount of ongoing habitat conservation work has been undertaken, much of it in the framework of successive EU-funded LIFE projects, to control invasive plants and restore native vegetation (http://life-terrasdopriolo.spea.pt/en/). It is therefore timely to review the species’ status and assess whether these actions have been sufficiently successful to warrant downlisting.
Population censuses in 2008 and 2012 confirmed that the species’ population trend is at least stable and probably increasing, mirroring the results of annual monitoring between 2008 and 2014 (Gil et al. 2016). In 2012, the total breeding population size was estimated as 227-761 pairs or roughly 454-1522 mature individuals (Veríssimo 2013), the Extent of Occurrence (EOO) as 137 km2 and the Area of Occupancy (AOO) as 90 km2 (Gil et al. 2016).
Although its population and range size remain very small, the species is not declining or fluctuating, so it does not trigger Criteria A, B or C. In 2012, the lower (454) and mean (988) estimates of its population size met the threshold (<1,000 mature individuals) for Vulnerable under Criterion D1. At 90 km2, its area of occupancy is too large (>20 km2) to trigger Criterion D2 on the basis of range size. However, it remains restricted to a single location on one island, such that it is prone to the effects of human activities or stochastic events within a very short time period in an uncertain future, and is thus capable of rapidly becoming Critically Endangered or even Extinct, which does trigger Criterion D2 (<6 locations).
Consequently, it is proposed to downlist the status of this species to Vulnerable (D1+2) in the 2016 IUCN Red List. Comments on this proposal would be welcome, as would any information about whether the growing population now exceeds 1,000 mature individuals (500 pairs). The objective of the EU Species Action Plan is to achieve and maintain a population of >1,000 pairs by 2019 (Teodósio et al. 2009).
Gil, A., Ceia, R., Coelho, R., Teodósio, J., Sampaio, H., Veríssimo, C., Heleno, R., Ramos, J. and Timóteo, S. (2016) The Priolo Atlas: A citizen science-based census initiative for supporting Pyrrhula murina habitat conservation and restoration policies in São Miguel Island (Azores, Portugal). Ecological Engineering 86: 45-52.
Teodósio, J., Ceia, R. and Costa, L. (2009) Species Action Plan for the Azores Bullfinch Pyrrhula murina in the European Union. http://ec.europa.eu/environment/nature/conservation/wildbirds/action_plans/docs/pyrrhula_murina.pdf
Veríssimo,C. (2013) Monitorização de Priolo Pyrrhula murina 2012. Sociedade Portuguesa para o Estudo das Aves (SPEA), Lisbon (unpublished report).