Largely confined to the north of the UK, the rare pine marten is mostly nocturnal and very hard to spot. Reintroductions are helping it make a comeback.

The house sparrow is a familiar, streaky brown bird of towns, parks and gardens. Males sport a grey cap and black bib, the size of which indicates their status.

The tiny, grey-brown house mouse is one of our most successful mammals. It thrives around buildings but is less likely to be found in our houses these days due to better construction.