Extinction Risk: A Comparative Analysis of Central Asian Vertebrates

In 2004, IUCN listed 20% of all mammals, 12% of birds and 4% of reptiles as threatened with extinction. Why are these species, but not the others in their clades, at risk? Most comparative studies of Red List status to date have investigated the relationship between status and life history or ecology, either at a local level where species face a given situation which may be known in detail, or at a global level where threats are much more heterogeneous. The use of data at a sub-global level raises several issues, including the need to assess populations across geopolitical borders and how best to treat non-breeding phases of populations. However, regional-level data provide the opportunity to look in more detail at how threatening processes operate. We employ comparative analysis using phylogenetically independent contrasts and multiple regression to control for inter-related and confounding independent variables, to evaluate correlates of regional threat for three groups of central Asian vertebrates. We find that aspects of dispersal, area of occupancy, body mass and generation time are important in predicting the perceived risk of regional extinction.