12 species have been put on the first "red list" for wild mammals in the UK.
A species that makes it on to the "red list" means it is called "threatened" and it faces going extinct within the next decade.
The highest threat category is "critically endangered." Three species were given this status: the wildcat, the greater mouse-eared bat, and the black rat.
The next highest threat level is "endangered". Listed here is the red squirrel, along with the beaver, water vole and grey long-eared bat.
The third-highest threat category is "vulnerable". The hedgehog, the hazel dormouse, Orkney vole, serotine bat and barbastelle bat are included in this list. The hedgehog and water vole have seen their populations decline by almost 70% over the past 20 years.
The species reported as increasing in number were the otter, pine marten, polecat and badger along with red and roe deer, the greater and lesser horseshoe bat, and beaver and wild boar.