Photo: Tony Tilford. Winter visitors from Scandinavia, fieldfares can be found breeding in western Europe through to Russia. Outside their breeding range, they can also be seen in North Africa and Iceland
The influx of huge flocks of fieldfare from their breeding grounds in Scandinavia to the UK each November signals that winter has truly arrived. But there’s much more to this colony breeding, berry-loving and vociferous thrush than meets the eye, says BILL NAYLOR.
A BIRD of winter, the fieldfare has many country names including the apt “snowbird”. “Fieldfare” is an old English word that literally means “traveller over the fields”. In Scotland, it is called “hill bird”, while in the Lake District, local country lads like myself knew these birds as “felts” or “fell-fares” – the dialect names that William Wordsworth used. Other names, such as “blueback”, refer to the bird’s distinctive blue-grey rump patch.
In striking contrast to redwings and other thrushes, fieldfares have a habit of rising vertically into the air, displaying their grey head and rump. And it’s the slate-grey colour that dominates the view of fieldfare flocks as they sweep over fields and moorland. It is said to be the largest British thrush but, in fact, it is midway in size between a song thrush and a mistle thrush. The sexes are alike.
Although fieldfares are feisty, in the wild they are very sociable and mix freely with redwings – our other winter-visiting thrush, which is smaller, lacks the grey plumage and resembles the song thrush. They will chatter constantly, with the scattered groups regularly coming together. In windswept areas their voices are loud and easily identified by their characteristic “chack-tchack-chack” call, from where their “Jack bird” name derives. In Sweden this has earned them the name “snow magpie”.
While they are usually colony breeders, in an aviary fieldfare are not particularly good mixers. When housed as a group they often squabble and, consequently, a pair is best housed in their own aviary. They are more vocal than other thrushes, uttering their “chuckling” type call.
The fieldfare’s alarm call is loud, giving rise to the names “screech bird” or “screech thrush”. It shares these names with the mistle thrush. Fieldfares don’t skulk on the ground under bushes as song thrushes and blackbirds do. In captivity they prefer to perch high, but do forage in leaf and bark litter. Like all thrushes, they are continually active, so a large aviary is recommended to satisfy their curiosity and restless nature.
Their diet includes insects, mainly beetles and caterpillars, and earthworms. Snails are broken by being beaten against a stone in song thrush style. But fieldfares feed chiefly on berries and are more dependent on these than any other British thrush. Virtually all types are consumed in the wild and in captivity: holly, yew, ivy, rowan, hawthorn, juniper, ivy and rose hips.
Usually birds of open country, when crops were left to overwinter in the fields, they would even feed on turnips and other roots. When weather is harsh they can now be found in parks feeding on berries of cotoneaster, pyracantha and other non-native shrubs and trees. Apple windfalls will encourage them to visit your garden. In captivity, they are very fond of blueberries, halved apples and pears.
Frank Meaden fed them on beef heart, cheese and softbill mixtures. Like any birds that regularly migrate, they rapidly build up stores of fat and are prone to put on weight. Close confinement and a diet rich in carbohydrates can quickly make them obese. Hand-reared birds especially can easily become overweight.
By spring, the dark parts of a fieldfare’s beak have turned yellow and the grey plumage is now pristine. Unusually for a thrush species, fieldfares are one of the few inland birds that nest in colonies,
though this is not invariably the case.
In a nesting colony, nests are aggressively defended and it’s during the breeding season that the male utters his warbling song. Their favourite nesting locations are small copses of beech trees – in Sweden it’s sometimes called the “beech thrush”. In Lapland, they nest in the numerous swathes of birch trees, some only 90cm (3ft) high. In places where there are few trees they won’t hesitate to nest on the ground, usually behind a grassy hillock.
If entering a fieldfare nesting colony, you will be made to feel as unwelcome as possible. The birds dive-bomb trespassers and often splatter them with droppings. In captivity, they are just as territorial when breeding, with the male being the main aggressor.
In 2004, a study of fieldfares in Norway revealed that they have a clever breeding strategy to outwit predators. It also dispelled the belief that fieldfares are difficult to breed in captivity. Although they usually nest in colonies, these birds rarely nest in the same location twice.
The 2004 study discovered the rise and fall of rodent populations dictated whether local fieldfares chose to nest in colonies. In years where rodent populations had plummeted, ravens and stoats instead targeted fieldfares – especially nesting birds and their eggs. In those years, fieldfares tended not to nest in colonies, instead nesting in isolation. When nesting solitarily they were much less vocal and uncharacteristically didn’t sound alarm calls when stoats or ravens were in the vicinity. Instead, they depended on individuals of other bird species to alert them to the presence of a predator.
Nesting can take place in southern areas as early as April, where there are normally two clutches, or as late as June in northern latitudes. The nest is constructed out of grasses, plant tendrils and moss, cemented together with mud and woven into a cup-shaped nest. It is conspicuous from the ground and almost always in the fork of a tree adjacent to the trunk. In captivity, fieldfares will nest on a tray ideally camouflaged with a few beech branches. According to Dave Coles’s First Breedings in Captivity, the first UK captive breeding success was in 1969.
The female incubates a clutch of five to six green/blue eggs with red-brown spots for 14 days. Nestlings are fed on insects and invertebrates, chiefly caterpillars and earthworms. They fledge after two weeks and are independent after another two weeks. Youngsters are light brown, spotted above and below, until the autumn moult after which they resemble the adults.
A few fieldfares arrive in the UK from northern Europe in October, sometimes even in September. But when the main flocks fly in from Scandinavia in November you know winter has set in. Most fieldfares remain in Scandinavia, but during bad winters flocks will even migrate from Russia. Their expansion into Europe has increased.
Out of the thousands of fieldfares that visit the UK, most leave in the spring and those that breed here can be counted on one hand – usually in northern England and Scotland. The first recorded breeding wasn’t until 1967 in Orkney. In Europe, however, there have been more breeding successes. Previously only a winter visitor to Germany, Holland and Switzerland, it now breeds regularly in those countries.
Climate change, which may make the winters less inhospitable and summers longer in Scandinavia, could mean that
the berry crop that fieldfares depend on is more plentiful in their homeland. This grey-headed “Jack bird” could then become a less common winter visitor to the UK. That would be a sad loss.
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