Photo: Berry raider: redwings often visit gardens to gorge on fruit early in the morning, then slip away as soon as the curtains are opened
Bill Naylor hails that cracking little thrush, the redwing, which swarms to Britain every year from its Continental base
THE smallest European thrush, the redwing (Turdus iliacus) is our commonest winter migrant. These birds arrive in September and October, with most of them leaving in March. Approximately a million redwings spend the winter months in the UK.
If winters are particularly hard with poor berry crops, redwings will migrate further south to continental Europe, North Africa and Asia. Every year, Scandinavian and Russian redwings of the race iliacus migrate to middle and southern England, while Icelandic birds of the race coburni, which is darker than iliacus, arrive in Scotland.
Redwings habitually migrate by night and their familiar tseep call can be heard in October nights from overhead flocks. They remain in loose flocks while they move inland in the UK, often in the company of that much larger, grey-headed thrush, the fieldfare (T. pilaris). Another migrant from Scandinavia and Russia, the fieldfare has a similar breeding range and wintering location and often migrates with redwings in mixed flocks.
Redwings are often attacked by hawks, both while migrating and when they have arrived in the UK. In a mixed flock of song thrushes, fieldfares and redwings, it’s usually the redwings that are targeted. The males don’t sing their full sweet melodic song until they are in their breeding area. They also have a buzzing-type contact call and a rattling alarm call, similar to but not as strident as that of the blackbird.
As mentioned, song thrushes are also often seen with these two northern thrushes, but the redwing can be distinguished from our native songster by its rusty red flanks and vivid cream stripe running above the eye. Typically, another horizontal cream stripe runs along the face from the lower beak, but in some individuals, it’s broken up and not as obvious.
The name “redwing” derives from the combination of chestnut red on the flanks and the yellowish-orange under-wing coverts, which produce a flash of fiery red when the bird takes flight. Redwings are usually active and always conspicuous, and more likely to be seen in open country. In urban areas, they are more common in parks and orchards than in gardens. However, they are attracted to gardens for falling apples and hawthorn berries. “Redwing thrush”, “redwing throstle” or “redwing Mavis”, are some of its country names. In Germany, they frequent country vineyards and have earned the name “vineyard thrush”, which is still used there. This became mistranslated here as the “wind thrush.”
Wild feeding preferences
When redwings first arrive in the UK, they are usually seen on the ground foraging for molluscs, worms and invertebrates. A study of redwings on Holy Island, Northumberland, found they fed mainly on snails. These are dealt with using the same bashing method employed by the song thrush. When livefood becomes scarce, these birds will feed on seeds, fruit and berries of an extensive set of plants including, cotoneaster, holly, ivy, buckthorn, juniper, yew, hawthorn, cherry, pine and whitethorn yew. Although redwings don’t readily enter small gardens, a selection of those plants may tempt them. They are also seen in fields of overwintering crops foraging for livefood. In Spain, among olive groves, they eat a lot of this fruit and their insect parasites.
An active and social bird, a pair of redwings requires an aviary at least 3m (9ft 10in) long. Tall conifers can be located at the rear of the flight; a bird native to the northern conifer forests, they are a favourite for roosting. However, if a flight is furnished with too much foliage, they will usually hide. Therefore, low-growing shrubs such as box, hebe and short conifers are more suitable for the middle and foreground of the aviary. Tree bark will enable them to forage and use the energy they always seem to have plenty of. Like all thrushes, they are enthusiastic bathers and will appreciate an appropriately sized pond.
In captivity, they will eat a variety of food, including any livefood, but readily accept an insectivorous mixture. If a flat stone is provided, it will be used as an “anvil” for breaking snail shells. There is no need to dice fruit, as halved apples and pears will be pecked until there is little left. Grated cheese added to the mixture will supply calcium and protein. Coming as they do from the harsh northern areas where scarcity of food even for a short while often means death, redwings always seem to be seeking food. Consequently, in captivity, over-feeding can be a problem. To curb their tendency to gorge on insectivorous mixtures, livefood and other protein-rich foods, it’s advisable to supply plenty of halved apples, pears and whole grapes. When offered in captivity, berries are sometimes not eaten as enthusiastically as in the wild and need to be fresh and not faded in colour.
Frank Meaden, British bird expert and first UK breeder of this species, stated that this was the only thrush that could be bred on the colony system. However, an extremely large aviary had to house the maximum of two to three pairs. Even then, they will still bicker non-stop. Like all thrushes, when ready to nest, the hen carries large amounts of nest material in her beak and searches for an ideal nest location. In Iceland, where trees are scarce, redwings frequent lower scrub vegetation and often nest close to the ground well camouflaged. Still, as with most thrushes, the location of the nest allows the sitting bird to view the surrounding area.
Trees, bushes, tree stumps and even holes in walls will be used for nesting. In captivity, an open-fronted box will often be utilised. A nest similar to that of a blackbird is constructed from grass moss and lichen cemented together with mud, dead grass and leaves. Moulded dead grass or leaves line the cup. The hen incubates five or six blue, brown-flecked eggs for 10-14 days. Both parents are highly protective of the nest and aviary birds when nesting will launch themselves at an intruder – human or otherwise – if the nest is approached.
A Swedish study over five years found the young are reared mainly on earthworms – a popular rearing food with most thrushes – and these usually contain soil that is full of minerals. In limestone areas, for instance, the calcium content in the soil is very high. A multivitamin mineral powder sprinkled on the livefood will ensure the young get enough nutrients and minerals. Flies, caterpillars, mayflies and beetles are also fed to the young. They fledge at 10-15 days, leave the nest shortly after that, and are fed for another fortnight by the male, while the hen often lays another clutch. Youngsters are initially spotted above and below. In autumn they moult to resemble the adults. As adults moult between June and September, they may be moulting while they are raising young. ■
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