The treecreeper (also from photos taken in Scotland) is small, very active, bird that lives in trees. It has a long, slender, downcurved bill. It is speckly brown above and mainly white below. It breeds in the UK and is resident here. Birds leave their breeding territories in autumn but most range no further than 20 km. Its population is mainly stable.
Fascinating fact: Treecreepers always climb upwards on a trunk, often spiraling around the tree as they go. When they reach the top, they fly to the bottom of a new tree and start again. Only the nuthatch can go down as well as up!