Effects of illegal logging on Amazonian medium and large-sized terrestrial vertebrates

Elildo A.R. Carvalho Jr., Reserva Biológica do Gurupi, Instituto Chico Mendes de Conservação da Biodiversidade
Eloísa N. Mendonça, Reserva Biológica do Gurupi, Instituto Chico Mendes de Conservação da Biodiversidade
Alexandre Martins
Torbjørn Haugaasen

Description

Selective logging is a major form of land use in tropical rainforests, with more than half of the world’s tropical forest already explored. In the Brazilian Amazon, most logging operations are illegal and highly damaging to forests. However, the effects of illegal logging on wildlife are poorly studied. Here we investigate the effects of illegal logging on the assemblage of medium- to large-bodied terrestrial vertebrates at the Gurupi Biological Reserve, a protected area in extreme eastern Amazonia that has been subjected to three decades of illegal logging. We used camera traps to survey the terrestrial vertebrate assemblage and visual interpretation of Landsat time series data (1984–2016) to assess the history of illegal logging (number of logging bouts and recovery time) for each camera trap site. Hierarchical Modelling of Species Communities (HMSC) indicates that logging had a minor effect on both the assemblage composition and individual species abundance. At the local level, the study demonstrates that the reserve effectively safeguards a significant portion of the regional biodiversity even though it suffered degradation by illegal logging. At a wider scale, the results suggest that illegally logged forests can retain much of their conservation value, if they are protected from further anthropogenic impacts such as hunting, fragmentation and fires. However, our study represents a best-case scenario, unlikely to be met in most other illegally logged areas in the tropics, where logging is usually followed by secondary effects that amplify its impacts.

 
Jan 1st, 12:00 AM

Effects of illegal logging on Amazonian medium and large-sized terrestrial vertebrates

Selective logging is a major form of land use in tropical rainforests, with more than half of the world’s tropical forest already explored. In the Brazilian Amazon, most logging operations are illegal and highly damaging to forests. However, the effects of illegal logging on wildlife are poorly studied. Here we investigate the effects of illegal logging on the assemblage of medium- to large-bodied terrestrial vertebrates at the Gurupi Biological Reserve, a protected area in extreme eastern Amazonia that has been subjected to three decades of illegal logging. We used camera traps to survey the terrestrial vertebrate assemblage and visual interpretation of Landsat time series data (1984–2016) to assess the history of illegal logging (number of logging bouts and recovery time) for each camera trap site. Hierarchical Modelling of Species Communities (HMSC) indicates that logging had a minor effect on both the assemblage composition and individual species abundance. At the local level, the study demonstrates that the reserve effectively safeguards a significant portion of the regional biodiversity even though it suffered degradation by illegal logging. At a wider scale, the results suggest that illegally logged forests can retain much of their conservation value, if they are protected from further anthropogenic impacts such as hunting, fragmentation and fires. However, our study represents a best-case scenario, unlikely to be met in most other illegally logged areas in the tropics, where logging is usually followed by secondary effects that amplify its impacts.