Blackbird, Eurasian blackbird
The Common blackbird (Turdus merula) is a species of true thrush. It is also called the Eurasian blackbird (especially in North America, to distinguish it from the unrelated New World blackbirds), or simply the blackbird where this does not lead to confusion with a similar-looking local species. This common and conspicuous species has given rise to a number of literary and cultural references, frequently related to its song.
The adult male has glossy black plumage, blackish-brown legs, a yellow eye ring, and an orange-yellow bill. The bill darkens somewhat in winter. The adult female is sooty-brown with a dull yellowish-brownish bill, a brownish-white throat, and some weak mottling on the breast. The juvenile is similar to the female but has pale spots on the upperparts, and the very young juvenile also has a speckled breast. Young birds vary in the shade of brown, with darker birds presumably males. The first-year male resembles the adult male but has a dark bill and weaker eye ring, and its folded wing is brown, rather than black like the body plumage.
Common blackbirds breed in Europe, North Africa, India, and southern China. Populations in the north and east migrate to winter in Egypt and the west and southeast of Asia. Depending on latitude, Common blackbirds may be resident, partially migratory, or fully migratory. These birds live in very varied habitats, including mountainous regions and big city centers, where they inhabit open forests and forest edges, woodlands, cultivated areas, gardens, and parks if the cover is dense enough for hiding.
Common blackbirds are diurnal and eat mainly on the ground, turning the leaf litter to find the invertebrates hidden below. The bird runs for a short distance and stops suddenly to turn its head sideways to detect its prey and hops while it digs the ground with its bill to attract worms. It will feed in trees and bushes on the fruits and berries that it prefers. These birds will often take sunbaths, while flattened on grass or warm ground, with their beak open and their head inclined, and wings and tails spread. Common blackbirds are territorial, strongly defending their territory, mostly in urban areas where each pair does not have much space. Females may also fight, in defense of a good nest site. While winter food is available, Common blackbirds will stay within their territory for the year, although they will occupy different areas. Migrating birds are more gregarious, flying in small flocks and eating in loose groups at the wintering grounds.
Common blackbirds are omnivores. They mainly eat cultivated fruits like apples, pears, strawberries, cherries, and grapes. They also eat wild berries and fruits, insects, spiders, earthworms, and some seeds, when hunting on the ground.
Common blackbirds are monogamous and pairs usually stay together for life. Courtship displays begin very soon, often in February. Males sing at dawn. An individual will fan its tail and raise it vertically while drawing its head into its shoulders until it looks like a black ball with a yellow beak. The female fluffs up the feathers of her neck and rump in answer to the male’s display. Common blackbirds breed in spring and are able to produce three clutches. Females build a robust nest within vegetation, low down but well hidden, located in the fork of tree branches. Usually, 3 to 4 eggs are laid, greenish and mottled with brown. The female incubates the eggs, sometimes relieved by the male for brief periods, and the chicks hatch in 12 to 14 days and leave the nest when they are 13 to 14 days old. They climb into the vegetation around the nest to hide, where both parents feed them for two or three more weeks.
Common blackbirds are widespread and not considered to be threatened. There have been local decreases, however, especially on farmland, possibly due to agricultural policies encouraging farmers to remove hedgerows (where the bird's nest is), increase their use of pesticides, and drain damp grassland, which may have reduced the amount of invertebrate food.
According to the IUCN Red List, the total Common blackbird population size is around 162 million to 492 million individuals. In Europe, there are about 40 million to 82 million breeding pairs, equating to 120 million to 246 million individuals. Estimates of national populations include: in China, around 100-100,000 breeding pairs; in Taiwan on migration, fewer than 50 wintering birds and fewer than 50 individuals; and in Korea, fewer than 50 individuals migrating and fewer than 50 wintering birds. Overall, currently, Common blackbirds are classified as Least Concern (LC) and their numbers today remain stable.