Minimizing the biodiversity impact of Neotropical oil palm development

Abstract

Oil palm agriculture is rapidly expanding in the Neotropics, at the expense of a range of natural and seminatural habitats. A key question is how this expansion should be managed to reduce negative impacts on biodiversity. Focusing on the Llanos of Colombia, a mixed grassland-forest system identified as a priority zone for future oil palm development, we survey communities of ants, dung beetles, birds and herpetofauna occurring in oil palm plantations and the other principal form of agriculture in the region--improved cattle pasture--together with those of surrounding natural forests. We show that oil palm plantations have similar or higher species richness across all four taxonomic groups than improved pasture. For dung beetles, species richness in oil palm was equal to that of forest, whereas the other three taxa had highest species richness in forests. Hierarchical modelling of species occupancy probabilities indicated that oil palm plantations supported a higher proportion of species characteristic of forests than did cattle pastures. Across the bird community, occupancy probabilities within oil palm were positively influenced by increasing forest cover in a surrounding 250 m radius, whereas surrounding forest cover did not strongly influence the occurrence of other taxonomic groups in oil palm. Overall, our results suggest that the conversion of existing improved pastures to oil palm has limited negative impacts on biodiversity. As such, existing cattle pastures of the Colombian Llanos could offer a key opportunity to meet governmental targets for oil palm development without incurring significant biodiversity costs. Our results also highlight the value of preserving remnant forests within these agricultural landscapes, protecting high biodiversity and exporting avian 'spill-over' effects into oil palm plantations.

Land-use effects on local biodiversity in tropical forests vary between continents

“…The magnitude of the effects varied among continents and with land-use intensity: intensively used plantations in Asia and Africa had particularly low species richness. These results agree with previous studies that found plantations to be highly detrimental to biodiversity (Barlow et al 2007b;Brühl and Eltz 2010;Edwards et al 2010;Freudmann et al 2015;Gilroy et al 2015), especially if they are managed intensively (Faria et al 2007;Clough et al 2009;Tadesse et al 2014;Newbold et al 2015). The low biodiversity in intensive plantations is likely to reflect the lack of structural complexity and the homogeneity in the age of the stands (Fitzherbert et al 2008;Clough et al 2009;Foster et al 2011;Freudmann et al 2015).…”

Managing Neotropical oil palm expansion to retain phylogenetic diversity

“…; Gilroy et al . ). In Colombia, the agricultural habitat most available for conversion to oil palm is cattle pasture (Garcia‐Ulloa et al .…”

“…; Gilroy et al . ), although forest succession on these lands could be another beneficial pathway for biodiversity and carbon sequestration (Gilroy et al . ).…”

The Impacts of Oil Palm Agriculture on Colombia's Biodiversity: What We Know and Still Need to Know

“…Seven publications were related to environmental issues such as carbon and greenhouse gases, and eight papers focused on the socioeconomic aspects and history of oil palm development in Colombia. Only three papers were related to landscape planning or land-use change [34][35][36], and, notably, just three were related to biodiversity: one included birds, dung beetles, ants and herpetofauna [37], another snakes [38], and one was related to ants [39].…”

“…Gilroy et al [37] compared the diversity of ants, dung beetles, birds, and herpetofauna in oil palm plantations versus cattle pastures in the foothills of the Eastern Zone. They showed that in all four taxonomic groups, oil palm plantations have similar to or higher species richness than improved pasture.…”