Goldcrest
Britain's smallest bird — the goldcrest weighs as little as a 10-pence coin, and at 4–7 g is the joint-smallest bird in Europe alongside the firecrest; a tiny olive-green bird with a bright stripe on the crown — yellow in females, orange-red in males, displayed when excited; common in coniferous woodland and one of the most abundant British birds despite suffering severe losses in cold winters.