Saturday 18 July 2015

Some common British birds' nests

Song Thrush's nests are easily recognized by the hard mud lining, typically placed in a hedge or thick shrub. Although this one was up against the wall of our house, we couldn't prevent predation of the young chicks - either by Magpie or Jay. We didn't catch the culprit red-beaked.  

Similar in size to a Song Thrush nest, the Blackbird lines its nest with grasses. Both species lay four or five eggs, and in a good year raise two broods. By mid-July the males stop singing until next March, depriving us all of what must be my favourite birdsong. 

The tiny Wren punches above its weight: both in the volume of its song and the size of its nest. The mossy nest is always domed, with a small side-entrance, typically in low bushes or ivy against trees or walls. This one, which successfully fledged a family in June, was in ivy and clematis, against the wall of the old garden privy, now our tool-shed. Male Wrens build several nests each spring, and let the female choose which to use. The other nests are often used as roosts. They are also double-brooded, and usually lay five or six eggs.  

The Dunnock is one of our commonest but most understated garden residents. Their mossy nests are placed in low bushes, brambles or hedges; and the four or five pale blue eggs are incubated only by the female. Their shy retiring character belies an unexpected sex life: analysis of eggs in a nest reveals that many females have two or more partners.  Cuckoos sometimes victimize Dunnocks, but these days (as Cuckoos have drastically declined), Meadow Pipits and Reed Warblers are more usual hosts.  

Until recently, the Blackcap (one of our most tuneful warblers) was strictly a summer visitor, wintering in Africa; but now many stay in the UK, surviving our milder winters on ivy-berries, insects and (increasingly) bird-tables. The flimsy nest is usually placed in low bushes or brambles, and again four or five is the usual clutch size. The male is illustrated here: females and young have a chestnut cap.  

Blue Tits take readily to bird boxes, and can be attracted to most gardens. One pair successfully nested this year in our garden in the top of a roll of roofing felt. The nest itself contains moss, animal hair, and often wool and feathers. Adults will readily come to a basket of hair or wool put out in early spring to provide easy nest material. The female lays about ten eggs, and the huge outlay of energy in fledging such a large brood ensures that pairs only nest once in a year. 

Typically building on a ledge or rafter in a barn, the Swallow devotes its entire summer to raising two or three broods. The nest is a mixture of grass and mud. Occasionally they build an unsupported nest against a wall, like a House Martin's, but with an open top. The clutch is of four or five white eggs, with reddish-brown freckles. Unlike the Blackcap, Swallows always migrate across the Sahara each autumn, and many winter as far south as South Africa. 

The Chaffinch's cheery song starts in February and heralds another breeding season. The beautifully constructed nest is usually well hidden in a hedge, bush or tree. It is carefully woven of moss and grasses, lined with hair and decorated on the outside with cobwebs and lichens. Four to six eggs are laid, and usually only incubated by the female. The male is illustrated here - females and young have more sober plumage.

 The Goldfinch also builds a neat, compact nest: usually in a tree or tall bush, and often in a fruit tree. Their twittering song - at its best rich and canary-like - is one of the joys of our garden, heard in any month. We attract them here with a year-round offering of niger seed, supplemented by sunflower hearts from October to April. From July the adults bring their plain-faced young to the feeders, but the gold wing-bar is characteristic from the moment they fledge.

Not obvious from these photos, a Greenfinch nest is usually much more untidy than a Goldfinch's. They always choose a bush, tree or creeper on a wall, usually between 4 and 15 feet up. Grass and moss are the main materials used, sometimes on a base of small twigs, (though not as much as a Bullfinch's). Hair and feathers are used as lining. Four to six whitish eggs are laid, with some reddish speckles. As with most birds in this post, incubation is about two weeks, as is the fledging time (i.e. the time from hatching to leaving the nest). 

 A pair of Bullfinches often nest in one of our hedges: when feeding young the pair usually arrive and depart together. The rather untidy, twig-based nest contains five greenish-blue eggs. Only the male is brightly coloured; in most species as dimorphic as this, only the female attends to nesting duties. Two broods are normal. (My thanks to Richard Fitter's classic Pocket Guide to Nests and Eggs, first published 1954, for many of the facts and figures. R.A.Richardson's wonderful illustrations were an important part of my childhood). 

The Linnet has declined rapidly in Britain; but loose colonies are still common especially in gorse bushes. In June a large flock feeding on local rapeseed surprised me - typical winter behaviour occurring in the breeding season. The nests in this collection belong to Montgomeryshire Wildlife Trust; many were donated by Paul Roughley. All were collected after the nesting season. My thanks to the Trust and to Paul. When displaying them at our recent village show, I was asked if I had made all the nests!