The tiny Eurasian wren is the UK’s most common bird but is very secretive and shy so hard to spot. It is constantly on the move, usually staying near the ground, but will sometimes hop up the lower part of a tree trunk or flit away on its short, round wings.
Its scientific name is from a Greek word ‘troglodytes’ meaning ‘cave-dweller’ which refers to its habit of disappearing into crevices and cavities in search of food or to roost. During cold weather it will often gather with other wrens at night, roosting together to keep warm in dark, snug holes.
Breeding birds: 8,600,000 territories
Wrens are tiny birds with reddish-brown upperparts with fine darker brown bars on the wings, tail, and rump. Then underparts are pale brown with heavy, darker streaks on the flanks and belly. They have a short, rounded tail which is chestnut coloured with dark brown streaks.
Wrens have darker a head and nape with fewer streaks and a pale supercilium from the base of the bill to behind the eye. They have long, slender, slightly down-curved bills with a black upper mandible and a yellow lower mandible. Eyes are dark brown, and legs and feet are pale brown. Male and female wrens look similar.
Juvenile wrens are redder with a streaked head and nape and darker underparts streaked with dark brown.
Wrens breed between April and July producing one or two broods a season.
They build their nests in old stumps, woodpecker holes, rock crevices, brambles, and hedges. The nest is a dome-shaped structure with a side entrance hole made from sticks, moss, lichen, and dead leaves. Males build 3 or 4 nests. The female chooses one which she then helps to line with feathers and hair.
Wrens lay 4-7 white eggs with brown spots that the female incubates alone for 12-10 days. Chicks are altricial and covered with sparse grey down on the head and the back. They are cared for by both parents. They fledge at 3 weeks, but their parents will feed them for a further 40 days.
Wrens’ diet consists of insects and spiders as well as small vertebrates such as tadpoles and small fishes. They will also eat seeds and berries.
Wrens can be found throughout the UK and are a regular visitor to gardens. They can also be spotted on farmland, heathland, moorland and woodlands.
The Eurasian is the only species of wren to be found outside of the Americas where there are no fewer than 83 recorded species of wren.