Treecreeper (Certhia familiaris) roosting at night in a hollow in the spongy, fibrous bark of a Sequoia (Sequoia sempervirens), which it has excavated. By fluffing up its plumage it can fill the hole and retian more heat. This Sequoia tree is over 150 years old and was brought over to Scotland from California. Aigas Field Centre, near Inverness, Scotland, UK. October.