Authors: Pacifici, Michela; Cristiano, Andrea;Lumbierres, Maria;Mallon, David;Tognelli, Marcelo;Belant, Jerrold;Lucherini, Mauro;Meijaard, Erik;Solari, Sergio;Rondinini, Carlo;

The average rate of loss of vertebrates is now up to 1000 times higher than background rates, with mammals being particularly affected by human activities. Broad-scale destruction of natural habitats, in particular tropical forests, is one of the primary sources of species loss. However, the lack of data on species’ distribution and fine-scale changes in habitat for the recent past have prevented comprehensive threat assessments. We collected data on the distribution of >450 mammals in the 1970s-80s that lost at least part of their range in the past 50 years, then we calculated the amount of habitat currently available within the lost and retained portions of the range. We found a net discrepancy between the habitat available in retained areas compared with lost areas, where the latter contained significantly less habitat. This trend was particularly evident in large mammals and in almost all land regions identified by IUCN. Understanding the role of habitat degradation in recent range dynamics and identifying species and areas most affected can help prioritize conservation interventions.