Research
Group - Mariana Vale
Mariana Vale is a current graduate student of Professor Stuart Pimm at Nicholas School of the Environment and Earth Sciences.
I have a B.A. in Ecology from the Federal University of Rio de
Janeiro, and a M.A. in Conservation Biology from Columbia University.
I am now a Ph.D. student with Stuart Pimm at Duke University. I
am interested in conservation, deforestation, and bird endemism
in the Brazilian Amazon. I have three research projects in the
region (see below). I am also the co-founder of the Pan-Amazon
Discussion Group: www.pan-amazon.org.
(Photo courtesy Alex Fattal.)
1 – Infrastructure Development and Bird Conservation
The lack of infrastructure has protected vast areas of the Amazon forest. This passive protection, however, is ending as Brazil implements a series of infrastructure projects in the region. Here we combine a future deforestation model with range maps to identify bird species that are likely to be threatened by 2020 due to infrastructure development. We identify 10 species that will reach a critical range size for threat: 2 Critically Endangered, 1 Endangered, 2 Vulnerable, and 5 Near Threatened. We also identify 12 species that are likely to be imperiled by loss of more than 50% of their habitat, and numerous taxa endemic to six ecoregions that are likely to be threatened.
2 – Conservation Status of Rio Branco Antbird and Hoary-throated Spinetail
The previous study suggests that two Passerine birds will be especially threatened by deforestation in the near future: of Rio Branco Antbird (Cercomacra carbonaria) and Hoary-throated Spinetail (Synallaxis kollari). Both species are vulnerable and found only in a limited area in northernmost portion of the Amazon. When we started this study little was known about these birds. We now know that the Rio Branco Antbird is less threatened than previously thought. The Hoary-throated Spinetail, on the other hand, has little habitat left and is more threatened than we thought. We also call attention to the importance of indigenous reserves and the conservation of these birds.
3 – Impact of Road Paving in Deforestation
Nearly 90% of the deforestation in the Brazilian Amazon has occurred within 100 km of major roads established under federal development programs. Despite past failures and the steady increase in deforestation rates, the Brazilian government is presently paving 6,245 km of roads in the Amazon. Some scientists predicted that road paving will increase deforestation in the Amazon while other come to the opposite conclusion. The BR-174 road provides the perfect test case to explore this issue. The northern portion of the road was paved in 1997 while the southern portion remains unpaved. I propose to use remote sensing to compare deforestation rates on the paved and unpaved sections in two periods: before and after the paving event. This study will predict whether or not deforestation rates increase or not after road paving.
Papers in Scientific Journals and News Articles:
- Vale et al. (in press). Abundance, Distribution, and Conservation of Cercomacra carbonaria and Synallaxis kollari. Bird Conservation International 17(3): in press.
- Vale et al. (2005). An incomplete nest of Poecilurus kollari in Roraima, Brazil. Cotinga Journal of the Neotropical Club 24: 111-112.
- Compationate Conservation by Patrick Adams (Duke Magazine)
- João do Lavrado by Vandré Fonseca (O Ecco)