Much more than forest loss: four decades of habitat connectivity decline for Atlantic Forest jaguars

Abstract

Context: Habitat loss is a major factor influencing declines in landscape connectivity for many species, but forest patch configuration and changes in matrix permeability can also represent important drivers. An evaluation of which of these factors are predominant is key to guiding landscape planning at a regional scale. Objectives: We aimed to quantify the loss of jaguar (Panthera onca) habitat connectivity and to analyse the drivers behind this process in the Atlantic Forest. Methods: We analysed trends in jaguar habitat connectivity between 1973 and 2015 in the Upper Paraná Atlantic Forest and the three countries that comprise the eco-region (Argentina, Brazil, and Paraguay). We used graph-based indices and jaguar movement data to evaluate changes in forest area, forest patch configuration and matrix permeability. Results: Jaguar habitat connectivity decreased throughout the entire period, with a loss of up to 93% of connectivity. Changes in forest patch configuration and forest area loss were the main drivers of this trend, but the effect of decreased matrix permeability was also significant. These processes together largely increased the negative effect of forest area declines on jaguar habitat connectivity. Connectivity trends for the three countries in the study area were negative, with the highest forest decline in Paraguay and Brazil compared to Argentina. Conclusions: Analysing landscape dynamics using metrics that go beyond measuring net forest area is key when assessing landscape connectivity for jaguars. Future studies evaluating landscape connectivity should incorporate habitat patch configuration and matrix permeability in addition to forest loss, aspects that should also be considered when undertaking habitat restoration measures.