A variety of threats are impacting mammal species around the world. To better understand the threatening processes affecting mammals, the assessment process recorded known threats to each species using a standardized list ( IUCN Threats Classification Scheme ) of major threats. Species are coded for past, present and future threats, and the summary shown here is for present threats only. Extinct species are only coded for past threats so are not included in this analysis. A summary of the number of species affected by each threatening process is shown in Figure 10.
By far the most significant threat to mammals is habitat loss with over 2,000 species being negatively impacted. The second most important threat is utilization, with almost 1,000 species affected, mostly in Asia. The impact of invasive species is probably a little underestimated as only threats to extant species are included here, and a significant proportion of species now considered Extinct were affected by invasive species.
Information has not been collected during the assessment on the relative importance of one threat compared with another for a particular species. Development of such information in the future is a priority and will enable a more complete analysis of significant threats to mammals.