Bird of the Month

by john mcewen illustrated by carry akroyd

The charm of the wren ( Troglodytes troglodytes, ‘cave dweller’) has earned it its ‘Jenny’ nickname and made it the emblem on our prettiest coin, the Victorian-designed farthing (withdrawn in 1960).

One July morning, I was greeted by a barrage of wren song, and this in the treeless depths of Olympia. At that otherwise songless time of the year, it was perhaps a newly-fledged brood finding their voices; a forceful reminder that it is our most ubiquitous bird, as at home in the concrete jungle as the wilderness, and has the most powerful song of diminutive songsters – per unit weight, ten times stronger than a cockerel’s crow. Moreover, it sings throughout the year, unlike most songsters, and females sing a little too.

The exuberant song is in keeping with its jaunty, up-turned tail: a torrent of lisped riffs with a linking brrrrrr, loud enough to pierce the roar of traffic or the sea. Like some other birds (robins, blackcaps), its alarm call is a time-bomb tickety-tick-tick.

Wrens are famous and eccentric nest-builders...

‘There was an Old Man with a beard, Who said, “It is just as I feared! – Two Owls and a Hen, four Larks and a Wren Have all built their nests in my beard.’ Edward Lear, A Book of Nonsense

Mousy by nature, it is more often heard than seen; hence its ‘cave dweller’ name. All habitats have its favoured nooks and crannies, also the abode of its preferred food, spiders. This adaptability explains its presence on far-flung St Kilda, where long isolation has created an endemic subspecies, the St Kilda wren ( Troglodytes hirtensis, after Hirta, largest of St Kilda’s four islands), a paler version of the russet mainland bird. Its fame has eclipsed other island sub-species on Shetland, Fair Isle and the Outer Hebrides.

Wrens have built their domed nests virtually everywhere, from inside a skull to the running board of a working lorry. They seem to like smelly places, so why not an unkempt beard?

Keep a wry eye out for a wren’s nest... Feathers and attentive eyes, crammed in the hot slum. Approach now and they stream out, one after the other, in a tracer fire of brown feathers, to skulk among the ticking foliage. Gerry Cambridge, from his poem Troglodytes Troglodytes

An odd characteristic is the habit of building false nests. The average is six, despite a complexity of design surpassed only by that of the long-tailed tit. The female’s choice is then softly lined. Hence the name ‘cocks’ nests’ for the unlined rejects. There are two broods of up to 10 eggs, with the young fed 50% on caterpillars.

In glacial 1963, four-fifths of the 20 million UK population (under half that today) died. A ‘hot slum’ is another cold weather defence, the birds cramming together. A Norfolk nest box harboured sixty birds one February night. These roosts get so tightly packed that an unlucky bird can be suffocated.