I HAD a few wrens (Troglodytes troglodytes) picking among my holly bushes the other morning.

From my kitchen door I thought at first they were mice hunting berries, but the binoculars showed tiny chestnut-coloured birds that looked remarkably like microscopic emus. OK, a bit of a romantic view but the wren is certainly one of our most romantic birds.

Weigh a pound coin in your hand. That’s what a fully grown adult wren will weigh. It isn’t actually Britain’s smallest bird — that honour goes to the goldcrest (Regulus regulus) — but the wren is Britain’s most common wild breeding bird.

There are about 8.5 million breeding pairs this year but the wren population can be devastated by a severe winter. The species’ high egg productivity means that wren numbers usually recover after few years.

Wrens don’t hibernate and many wrens remain here over winter. They have to continue to find whatever food is available — seeds or insects — as best as they can and at night they often gather together in large numbers for collective warmth.

They often crowd into empty nesting boxes or similar spaces. In some cases up to 90 wrens have been found in a single box. That’s an extreme obviously, but groups of two dozen or more are common.

The bird we know as simply the wren is more correctly known as the winter or European wren. Its Latin name comes from its habit of probing miniature caves or caverns.

Wrens live on a diet of spiders and insects which they find while hopping and dashing along the ground and probing in crevices with their long, thin bill.

Males will construct up to a dozen nests from which the females will choose one and then line it with moss, leaves or feathers. She will lay between one and nine eggs which only she incubates, though both adults will feed the young chicks.

The wren has been widely acknowledged for many centuries as rather special. The legend that, by guile, it proved itself to be the king of the birds is found throughout northern European folklore, but similar versions have been recorded in 13th-century Jewish writing, in India, in central Africa and among some North American tribes.

When it comes to legends, Ireland usually has a good version. The Irish tale recounts that all the birds gathered in a secret green valley on the south coast to discuss which of them should be king.

It was decided that the bird that flew the highest should take the crown and the eagle soared way above the other contestants — only to discover that a wren had hitched a lift among the eagle’s back feathers. 

At the last moment the wren launched itself just above the eagle and claimed the prize.

Even the Zulus have a version and it is different. The wren rides on a falcon to win the prize but is caught out for cheating. 

Imprisoned under the watchful eye of a wise owl, it waited until its gaoler nodded off and then escaped, spending the rest of time avoiding capture by darting from cover to cover.

The birds, which store very little body fat and lose heat easily, huddle together for warmth and protection rather like penguins, their heads inwards.

With winter food scarce, wrens may forage under the snow for their natural diet of insects and spiders, their small size allowing them into areas that other birds can’t penetrate, an ability that applies throughout the year as they can reach cavities denied to larger beaks.

However, they are cunning pragmatists and in the spring may vary their diet by visiting shallow water to pick up tadpoles and fish fry.

Wrens are famously good singers, and can hit two notes at the same time. For such a small bird, the wren has an astonishingly loud song.

The wren delivers its powerful song, which becomes an angry chatter when an intruder, human or otherwise, comes close by.

The female becomes particularly vocal if her newly fledged brood is on site, which may explain why wrens tend to be thought of as female, hence Jenny Wren.

Communist folklore specialist AL (Bert) Lloyd took a particular interest in the song The Cutty Wren. He discovered it had close connections with the 14th-century Peasants’ Revolt.

In the song folklore irony transformed the tiny wren into a magical gigantic powerful bird, a great fowl so hard to seize, so difficult to dismember but so suitable for sharing among the hungry poor.

In Lloyd’s opinion the song took on a strong revolutionary meaning during the Peasants’ Revolt of 1381.

In countless legends the wren features as a tyrant but in this song it became the symbol of baronial property, for which preparation for the seizure and redistribution to the peasants was to be carried out in the greatest secrecy.

Hence the coded message of the song full of symbolism and hidden meaning.

The wren was also sacred to the druids but rather cruelly they had the custom of catching and killing wrens at Christmastime. They were by no means the only ones to kill wrens.

Wrens were blamed for the death of St Stephen. Early Christians believed the bird had a pagan association and, in Ireland and on the Isle of Man, the bird was hunted on December 26 because it was said that St Stephen was betrayed to his persecutors by a noisy wren when he was hiding in the bushes.

Sadly the ritual murder of wrens became part of many turn of the year celebrations including Christmas Eve, Christmas Day, Old Christmas, Boxing Day, St Stephen’s Day, Twelfth Night, winter solstice and new year. 

Indeed any hint of a special day seemed to be sufficient excuse to murder a few wrens. This is curious and strange because at any time of year harming a wren is said to bring bad luck.    

Dead or captured alive and in a small cage, the wren was put on top of a decorated pole and paraded round the community. 

In Ireland and a few places in the north of England small boys still dress up — calling themselves wren boys they go around the streets and pub doors to collect coins. Wren boys sing a version of this song as they beg for small change.

The wren, the wren the king of all birds,
On St Stephen’s Day it was caught in the furze
Up with the kettle and down with the pan
Give me a penny to bury the wren.

If reading this has made you a bit sorry for the poor old wren, you can do what I do and put out a few mealworms, finely broken breadcrumbs, oatmeal and grated cheese. 

Put the food on the ground as wrens are very reluctant to visit bird tables. Perhaps they are worried it is some special day and wren killers are waiting in ambush.