Abstract Being an island, Britain has a relatively impoverished native mammal fauna compared with mainland Europe. This has been farther reduced by human activity, though other species have been introduced to raise the total number to 55. The distribution of most species is reasonably well known, but information about status is generally poorer and baseline surveys are still needed for most species. Human activity has strongly influenced the status and distribution of many species, particularly those that are sporting quarry or are considered to cause damage to human interests.