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Habitat destruction and overexploitation are the main threats to biodiversity and where they co‐occur, their combined impact is often larger than their individual one. Yet, detailed knowledge of the spatial footprints of these threats is lacking, including where they overlap and how they change over time. These knowledge gaps are real barriers for effective conservation planning. Here, we develop a novel approach to reconstruct the individual and combined footprints of both threats over time. We combine satellite‐based land‐cover change maps, habitat suitability models and hunting pressure models to demonstrate our approach for the community of larger mammals (48 species > 1 kg) across the 1.1 million km2 Gran Chaco region, a global deforestation hotspot covering parts of Argentina, Bolivia and Paraguay. This provides three key insights. First, we find that the footprints of habitat destruction and hunting pressure expanded considerably between 1985 and 2015, across ~40% of the entire Chaco – twice the area affected by deforestation. Second, both threats increasingly acted together within the ranges of larger mammals in the Chaco (17% increase on average, ± 20% SD, cumulative increase of co‐occurring threats across 465 000 km2), suggesting large synergistic effects. Conversely, core areas of high‐quality habitats declined on average by 38%. Third, we identified remaining priority areas for conservation in the northern and central Chaco, many of which are outside the protected area network. We also identify hotspots of high threat impacts in central Paraguay and northern Argentina, providing a spatial template for threat‐specific conservation action. Overall, our findings suggest increasing synergistic effects between habitat destruction and hunting pressure in the Chaco, a situation likely common in many tropical deforestation frontiers. Our work highlights how threats can be traced in space and time to understand their individual and combined impact, even in situations where data are sparse. [ABSTRACT FROM AUTHOR]

[Display omitted] • First map of Indigenous Peoples' Lands for the Dry Chaco region. • Indigenous Lands with secure land-tenure halt forest-loss in deforestation hotspots. • Over 40% of the remaining forests of the Dry Chaco are Indigenous. • Most Indigenous Peoples of the Dry Chaco have land-tenure insecurity. • Over 80% of the remaining forests of the Dry Chaco occur outside Protected Areas. Due to human activities, most natural ecosystems of the world have disappeared and the rest are threatened. At a global scale, 40% of the remaining forests occur in Indigenous Peoples Lands (IPL). While several studies show that IPL contribute to conserve forest-cover and halt forest-loss, other studies have found opposite results. The differing results on the role of IPL in forest conservation and loss are probably because of the effect of other variables, e.g. land tenure security. In this study, we addressed the role of IPL in forest conservation and loss, differentiating IPL with land-tenure security (IPL-S) and insecurity (IPL-I). We worked in a deforestation hotspot, the South American Dry Chaco region. First, we mapped IPL in the Dry Chaco. Then, covering the period 2000–2019, we measured forest cover and loss in IPL-S, IPL-I and in areas that are not Indigenous (non-IPL). Finally, we used a matching estimators method to statistically evaluate if IPL-S and IPL-I halt forest loss. To avoid bias, we accounted for the effect of variables such as Country (Argentina/Bolivia/Paraguay), Protected Area (yes/no), etc. We created the first map of IPL for the Dry Chaco, and found that at least 44% of the remaining forests are in IPL, and 67% of them are IPL-I. Our results also showed that IPL-S work as deforestation barriers. Inside PA, the effect of IPL-S was not always significant, probably because PA were already reducing forest loss. The effect of IPL-I on halting forest-loss was variable. We conclude that land-tenure security is key for IPL to reduce forest-loss, adding evidence on the importance of securing land-tenure rights of Indigenous communities for conservation purposes. At a regional scale, a large proportion of the remaining forests are Indigenous and conservation initiatives should be co-developed with locals, respecting their rights, needs and cosmovisions. [ABSTRACT FROM AUTHOR]

Aim Location Methods Results Main Conclusions Land‐use change and overexploitation are major threats to biodiversity, and climate change will exert additional pressure in the 21st century. Although there are strong interactions between these threats, our understanding of the synergistic and compensatory effects on threatened species' range geography remains limited. Our aim was to disentangle the impact of habitat loss, hunting and climate change on species, using the example of the endangered Chacoan peccary (Catagonus wagneri).Gran Chaco ecoregion in South America.Using a large occurrence database, we integrated a time‐calibrated species distribution model with a hunting pressure model to reconstruct changes in the distribution of suitable peccary habitat between 1985 and 2015. We then used partitioning analysis to attribute the relative contribution of habitat change to land‐use conversion, climate change and varying hunting pressure.Our results reveal widespread habitat deterioration, with only 11% of the habitat found in 2015 considered suitable and safe. Hunting pressure was the strongest single threat, yet most habitat deterioration (58%) was due to the combined, rather than individual, effects of the three drivers we assessed. Climate change would have led to a compensatory effect, increasing suitable habitat area, yet this effect was negated by the strongly negative and interacting threats of land‐use change and hunting.Our study reveals the central role of overexploitation, which is often neglected in biogeographic assessments, and suggests that addressing overexploitation has huge potential for increasing species' adaptive capacity in the face of climate and land‐use change. More generally, we highlight the importance of jointly assessing extinction drivers to understand how species might fare in the 21st century. Here, we provide a simple and transferable framework to determine the separate and joint effects of three main drivers of biodiversity loss. [ABSTRACT FROM AUTHOR]