Turdus viscivorus Linnaeus, 1758
Turdus viscivorus Linnaeus, 1758
Common names: Mistle thrush [En], Grive draine [Fr], Grote lijster [Nl], Misteldrossel [De], Tordela [It], Zorzal charlo [Es], Τσαρτσάρα [Gr], Ökse ardıç kuşu [Tu]
IUCN Status: LC (Least Concern)
Margaret Park, BUDAPEST ● Hungary
Description: The nominate subspecies measures 27–28 cm in length, with a 45 cm wingspan. It has a stocky upright posture when on the ground. It has pale grey-brown upperparts, the chin and throat are greyish-white, and the yellowish-buff breast and off-white belly are marked with round black spots. The spotting becomes denser on the lower chest, giving the appearance of a breast-band. The long tail has white tips on the outer feathers, and the underwing coverts are white. The eyes are dark brown and the bill is blackish with a yellowish base to the lower mandible. The legs and feet are yellowish-brown. There are no plumage differences between the sexes. Juveniles are similar to adults, but they have paler upperparts with creamy centres to many of the feathers and smaller spots on the yellowish underparts. By their first winter they are very similar to adults, but the underparts are usually more buff-toned.
Three subspecies are currently accepted:
• T. v. viscivorus Linnaeus, 1758 – Europe and Asia, up to the Ob River in Russia.
• T. v. bonapartei Cabanis, 1860 – Siberia up to Central Asia – Larger than the nominate form (30 cm) paler grey above and whiter below, with fewer black spots.
• T. v. deichleri Erlanger, 1897 – North Africa, Corsica and Sardinia – Resembles T.v. bonapartei in appearance but smaller and with a more slender bill.
Biology: Mistle thrushes feed mainly on invertebrates, fruit and berries. Animal preys include earthworms, insects and other arthropods, slugs and snails. Plant food includes the fruits and seeds of bushes and trees, mainly holly, yew, ivy and mistletoe, but also, for example, blackberry, cherry, elder, hawthorn, olive and rose. It may eat the flowers and shoots of grasses and other plants, and will take fallen apples and plums. It forages within its breeding habitat and in open fields, sometimes sharing these feeding areas with redwings or fieldfares.
As its name implies, the mistle thrush is important in propagating the mistletoe, an aerial parasite, which needs its seeds to be deposited on the branches of suitable trees. The highly nutritious fruits are favoured by the thrush, which digests the flesh leaving the sticky seeds to be excreted, possibly in a suitable location for germination.
Individuals or pairs will defend one or more fruit-bearing trees throughout the winter, mistletoe being preferred where available, with holly as the first choice elsewhere. Although the thrush normally feeds on the ground or other trees, the defence of this resource conserves the fruit for later in the season when other food items are becoming scarce.
Mistle thrushes breed in the year subsequent to their hatching; they are monogamous and stay as a pair throughout the year in areas where they are not migratory. The male will attack intruders into its breeding area, including birds of prey and corvids, and sometimes cats or humans. The nest is usually built in a tree in the fork of a branch or against the trunk, although hedges, ledges on buildings and cliff faces may also be used. The nest is built by the female, although the male may help.
The clutch is typically three to five eggs (range two to six), which are usually whitish-buff or greenish-blue and are spotted with red, purple or brown. The eggs are incubated for 12–15 days, mainly by the female. The chicks are altricial and downy, and are fed by both parents. They fledge about 14–16 days after hatching. There are normally two broods.
Habitat: The mistle thrush is found in a wide range of habitats containing trees, including forests, plantations, hedges and town parks. In the south and east of its range, it inhabits upland coniferous woodland and the range extends above the main tree line where dwarf juniper is present. Breeding occurs at up to 600 m in the mountains of North Africa, and occasionally much higher, to 1,700 m. In the highlands of Europe, its preferred altitude is from 800–1,800 m. More open habitats, such as agricultural land, moors and grassy hills, are extensively used in winter or on migration.
Distribution: The mistle thrush breeds in much of Europe and temperate Asia, although it is absent from the treeless far north, and its range becomes discontinuous in southeast Europe, Turkey and the Middle East.
The mistle thrush is a partial migrant: birds from the north and east of the range wintering in the milder areas of Europe and North Africa. Scandinavian and Russian birds start moving south from mid-September onwards, most birds wintering in Europe, western Turkey and the Middle East.
Wikipedia, Mistle thrush