The main direct pressures on global biodiversity are habitat stress and land-use change, invasive species, pollution, unsustainable use/overexploitation and climate change (mainly as a consequence of higher temperatures, changes in precipitation patterns and increasing frequency and severity of extreme weather events and wildfires) (UNEP 2012). The spatial distribution and combination of these pressures varies across the globe (Figure 6.3) and affects species groups in different ways (Figure 6.4), although detailed data for invertebrates, which comprise most of the diversity of life, are lacking (Collen et al.2012).
: Examples of global distribution of pressures on (a) threat intensity (H: high; L: low; M: medium; VH: very high; VL: very low) from terrestrial invasive alien species and (b) cumulative fisheries by-catch intensity for seabirds, sea mammals and sea turtles, by all gear types (gillnet, longline and trawl)
Sources (a) Early et al. 2016 (b) Lewison et al. (2014).
: Percentage of threatened (critically endangered, endangered and vulnerable) and near threatened amphibian, bird and mammal species by major threat class
Number of threatened species in each taxonomic class in parentheses. Threat classes were aggregated as follows: 1 = Residential and commercial development, Agriculture and aquaculture, Energy production and mining, Transportation and service corridors, Human intrusions and disturbance, Natural system modifications; 2 = Invasive and other problematic species, genes and disease; 3 = Pollution; 4 = Biological resource use; 5 = Geological events, Climate change and severe weather. Source: Maxwell et al. (2016) updated with International Union for Conservation of Nature [IUCN] (2018).