Mean detection/capture frequencies or relative abundances (number of independent photos/sample effort*100) of 23 terrestrial mammal species detected in oil palm plantations and riparian forests in Llanos, Colombia.

<p>Bars indicate the upper standard deviation range. Blue lines separate taxonomic orders (from left to right): Pilosa, Cingulata, Carnivora, Artiodactyla, Rodentia, Marsupialia. Note: A mouse species and two species of primates were also detected, but they are not included in this figure because the first could not be identified by camera trap and the latter are not ground dwelling mammals.</p

Terrestrial mammal responses to oil palm dominated landscapes in Colombia

<div><p>The rapid expansion of oil palm cultivation in the Neotropics has generated great debate around possible biodiversity impacts. Colombia, for example, is the largest producer of oil palm in the Americas, but the effects of oil palm cultivation on native fauna are poorly understood. Here, we compared how richness, abundance and composition of terrestrial mammal species differ between oil palm plantations and riparian forest in the Colombian Llanos region. Further, we determined the relationships and influence of landscape and habitat level variables on those metrics. We found that species richness and composition differed significantly between riparian forest and oil palm, with site level richness inside oil palm plantations 47% lower, on average, than in riparian forest. Within plantations, mammalian species richness was strongly negatively correlated with cattle abundance, and positively correlated with the density of undergrowth vegetation. Forest structure characteristics appeared to have weak and similar effects on determining mammal species richness and composition along riparian forest strips. Composition at the landscape level was significantly influenced by cover type, percentage of remaining forest and the distance to the nearest town, whereas within oil palm sites, understory vegetation, cattle relative abundance, and canopy cover had significant effects on community composition. Species specific abundance responses varied between land cover types, with oil palm having positive effects on mesopredators, insectivores and grazers. Our findings suggest that increasing habitat complexity, avoiding cattle and retaining native riparian forest–regardless of its structure–inside oil palm-dominated landscapes would help support higher native mammal richness and abundance at both local and landscape scales.</p></div

Relationship between landscape and habitat covariates and terrestrial mammalian richness in Llanos, Colombia as determined using a GLMM.

<p>Estimates correspond to the conditional averaged parameter coefficient and relative importance is based on the <i>w</i>AIC -Akaike information criterion.</p

Mammalian relative abundance responses to selected landscape covariates in Llanos, Colombia.

<p>Values indicate GLM model coefficients and colors represent the effect sizes on the relative abundance of each species (univariate analysis). Abbreviations: Plantations = oil palm plantation, one of the 2 levels of the categorical variable “cover type” (i.e., riparian forest, and oil palm plantations); x.for = percentage of forests in the 500 m-radius buffer; Dist.road and Dist.town = the average nearest distance to roads and towns (respectively); NDVI: Normalized Difference Vegetation Index. Variables were standardized for direct comparison.</p

Terrestrial mammal responses to oil palm dominated landscapes in Colombia - Fig 4

<p>Relationship between mammalian species richness as a function of landscape covariates in Llanos, Colombia: a) percentage of forest, b) NDVI, c) distance to towns, and d) distance to roads, according to land-cover type (oil palm plantations vs forest). The trend lines are predicted values of the GLMM model averaged (holding other covariates constant) and shaded areas represent the 95% confidence intervals. Dotted points represent the actual values of the covariate. Effect of land-cover type is strong, while the slope of continues variables does not show an important effect on species richness.</p

Sample-based rarefaction curves estimating medium and large terrestrial mammal species richness in Llanos, Colombia.

<p>Sample-based rarefaction curves estimating medium and large terrestrial mammal species richness in Llanos, Colombia.</p

Overall mammal community composition across surveyed sites in oil palm plantations (triangles) and riparian forest (circles).

<p>Plot is based on capture frequencies of species using Bray-Curtis non-metric multidimentional analysis (NMDS) (stress = 0.22). Polygons connect the vertices of each cover type and ellipses emphasize the centroids of the community in each land cover. Species outside the boundaries were very rare in the landscape. Codes correspond to the initial letters of the scientific names of each species (refer to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0197539#pone.0197539.s002" target="_blank">S1 Table</a>).</p

LaosVietnamDS2_merged

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MalaysianBorneoDS1_Pool1_merged

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Madagascar_Pool1_merged

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