Climate change and bird extinctions in the Amazon

deforestation projection (BAU) with unlimited dispersal, we found an average contraction of 95% of the suitable areas in which 11 species lost more than 90% of the adequate areas. Among these species that lost their entire suitable area are Pteroglossus bitorquatus bitorquatus, P. paraensis, Granatellus pelzelni paraensis, Tangara velia signata, and Lanio cristatus pallidigula (Table 2, S1 Fig). Moreover, these species also lost total habitat in the no-dispersal scenario, with an average loss of 90%. The limited dispersion context is the one that presents less drastic results compared to the other ones, since it indicates an average habitat loss of 78%, however, there was no suitable area expansion for any of the species. The bird species richness per cell in BAE ranged from 0 to 15 and 0 to 10 in the current and future projections, respectively, due to the lack of environmental suitability in the dispersal frameworks we assumed herein. In both optimistic and pessimistic projections, species riches are mainly concentrated in the central-eastern region of BAE in all dispersal frameworks. In addition to the concentration of bird species in this region, the projections for the business-as- usual scenario indicate the existence of adequate area fragments in the southwest portion of the BAE (Fig 3). In contrast, in the mitigation scenario, species richness is concentrated mainly in the middle east, middle west, and south regions (Fig 3). Moreover, the results reveal a low concentration of suitable areas near the Tocantins River and BAE’s northern region in all scenarios.

The limited dispersal scenario indicates the existence of adequate area fragments in the northeastern region of the BAE in both mitigation and business-as-usual scenarios. Such cir- cumstances suggest possible movements of species to this region since these areas harbor lower richness and distribution of species in the current climatic and deforestation conditions (Fig 3). The results also reinforce the importance of the protected areas existing in the BAE Fig 3. Maps of the potential distribution of endemic bird species from the Bele´m Area of Endemism. 1—“Gurupi Mosaic”; 2—“Rio-Capim” watershed. (A) represents the current climate suitability areas, while (B) represents the mitigation scenario, and (C) the Business-as-usual scenario. Regarding different dispersion contexts, sections (I), (II), and (III) demonstrate the Unlimited Dispersal, Limited Dispersal, and No Dispersal scenarios, respectively. Dispersal scenarios were applied to the projections. The mitigation and business-as-usual scenarios applied are projections constructed from perspectives of greenhouse gas emissions, and investments in conservation policies. Colors that vary between yellow and brown represent the number of species per cell in the projections. Both projections of forest remnants have been extracted from the SimAmazonia database [26]. https://doi.org/10.1371/journal.pone.0236103.g003 PLOS ONE Bird extinctions in the Amazon PLOS ONE | https://doi.org/10.1371/journal.pone.0236103 July 17, 2020 9 / 18