Breeding pairs: 5,100,000
Wintering birds: 10-15 million
Adult male blackbirds have black, glossy plumage all over. The bill is yellow, the eyes are dark brown with a yellow eye-ring, and the legs are black or very dark brown.
Female blackbirds are reddish-brown with mottling on the underparts. The throat is paler, and they have a buff malar stripe. The bill is brown with a yellow base, and the eyes and legs are dark brown.
Juveniles are dark brown with buff streaks on the upperparts and mottled underparts. The bill is brown.
After one year, young male blackbirds begin to resemble adults, but will still have some brown in the wings.
Blackbirds can suffer from leucism and may have several white feathers that contrast with the black plumage.
Blackbirds breed in spring can produce up to three clutches a year. Females build the nest alone sited in a shrub or a tree. It is an open bulky cup made from groups, roots, and sticks usually bound together with mud, and lined with fine grass.
Blackbirds lay 3-4 greenish blue eggs with reddish-brown spots. They are incubated by the female alone for 12-14 days, although the male may take over for very short moments. Both parents feed the chicks with fruit, insects, and worms. They fledge 10-19 days after hatching but are fed by their parents for another two or three weeks.
Blackbirds will forage on the ground for insects and worms, often turning over leaf litter to pick through it. From late summer to early winter they will often switch to a diet richer in fruit such as windfalls and berries. Blackbirds are softbills so struggle to deal with tough seeds and grain but will eat suet, raisins and other kitchen scraps from the ground or a ground feeding table.
Blackbirds can be seen all year round across in the UK. Look out for them in gardens and the countryside.
A waveform of a blackbird song is on the cover of Kate Bush’s album Aerial.