Reply to mjceaser
We have the European nuthatch, Sitta europea, here. You have probably seen the white-breasted nuthatch, Sitta carolinensis, which is apparently very common in much of North America. In Britain there is only one other little bird that runs on the bark. The treecreeper is mottled brown and only walks up tree trunks (as do the larger woodpeckers), using its tail as a support. The nuthatch walks up, down and sideways across the tree trunks.