Continental assessment of South American marsupial conservation priorities: A methodological approach using a spatially explicit conservation indicator

Abstract

The distributional range of South American marsupials is the response to evolutionary history, geology and climate, resulting in a chorology characteristic of each taxon. We integrated information for each species using the global conservation status given by the International Union for Conservation of Nature (IUCN), plus the taxonomic singularity, and the chorotype using an explicit conservation indicator: the pixel conservation value (PCV). We generated a map of South America with 0.5° × 0.5° grids, where we ranked areas with different conservation values (PCVs), analyzed their overlap with protected areas and human pressure, and tested their use with a recent disturbance (fires during August 2019) at a continental scale. The highest PCVs were found in the Andean region from Perú to northern Argentina, and in Brazil between the Paranaense Forest and the Cerrado ecoregions. Only 21.5% of the total PCV area was protected, with 60% to 0% of PCV areas protected. When human pressure and conservation scenarios were analyzed, 99.9% of all pixels are under some kind of pressure, with 33.3% and 66.7% under high and low pressure, respectively. We present comparative information between areas, and show examples of the usefulness of this indicator to quantitatively evaluate the impact of environmental disturbances on their conservative value.