Goldcrest © Steve Round
Goldcrests become even more widespread in winter, occupying an extra 110 tetrads compared to the breeding season. As noted by Coward (1910) and Bell (1962), they broaden their habitat use and are no longer defined by coniferous woodland, although, as in the breeding season, this is the species most likely to be found in that A2 habitat, recorded in 66 tetrads. They switch to a higher proportion of broadleaved woodland, with more broadleaved (157) than mixed (117) – reversing the breeding season order of 103 to 148 – perhaps because in winter, they have few competitors as insectivorous feeders amongst the twigs in the tree canopy. There are almost the same number of human site records: apart from a slightly warmer microclimate, the environs of habitation have little to offer Goldcrests in winter. The key factor in allowing it to spread out into the relatively tree-less areas is the winter occupation of scrub (51 winter records compared to 24 for breeding) and especially of farmland hedges (86 compared to 12). Thus, wintering Goldcrests fill in most of the gaps in their breeding distribution.
Most of the birds recorded in the extra tetrads, however, are likely to be different individuals. Breeding birds probably stay put on or near their territory (BTO Winter Atlas), and these are presumably those that are occasionally heard singing, even in the depths of winter. Juveniles disperse locally, with the population augmented by some Scottish birds moving south for the winter and some immigrants from northern Europe (Migration Atlas). Some birds move around within a winter. One ringed at Norton Priory, Runcorn on 31 December 1994 was found dead in April 1995 near Haverfordwest, Dyfed, 233 km southwest, a classic destination for a hard-weather movement.
They eat almost exclusively small invertebrates and it is remarkable that Britain’s smallest bird, weighing about 5 g, can survive through most winter conditions. They spend much of their time searching the undersides of leaves, the needles of conifers and twigs, so that snow affects them rather little, and the only adverse weather that impinges on their feeding is frosting or glazing of trunks and foliage. They forage at all heights from the neck-aching (for the observer) tops of tall trees to ground level if need be, with two reports of birds feeding on the ground in snow. One observer found two small flocks feeding on seed heads and on dead thistles, where it was most likely that they had found some invertebrate larvae or eggs amongst the plants, and in a garden at Poynton (SJ98B) Goldcrests had learned to feed on fat balls.
Some Goldcrests join mixed-species flocks, especially with Long-tailed Tits and other tits, usually squeaking as they go. Substantial flocks of ’crests are sometimes found: as many as 40 birds were reported in Little Sutton (SJ37T) and similar numbers in a hillside wood near Wildboarclough (SJ97V), with other flocks of around 25 in Abbots Moss (SJ56Z) and Woolston (SJ68U). But three-quarters of records were of just one or two birds, indicating the way that most Goldcrests lead their lives.
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