Great tit, Parus major.
The largest UK tit – green and yellow with a striking glossy black head with white cheeks and a distinctive two-syllable song. It is a woodland bird which has readily adapted to man-made habitats to become a familiar garden visitor. It can be quite aggressive at a bird table, fighting off smaller tits. In winter it joins with blue tits and others to form roaming flocks which scour gardens and countryside for food. Seen all year round. Eat insects, seeds and nuts. Still photo: @Nottsexminer on flickr. Video created by avibirds.com