resident populations. Predators and parasites Throughout the goldcrest's range, the main predator of small woodland birds is the Eurasian sparrowhawk, which has a diet consisting of up to 98% of birds. Merlins, tawny and long-eared owls also hunt goldcrests. The erratic movements and flights of small woodland birds, which are vulnerable to attack while away from cover, may help to confuse their predators. The goldcrest has only very rarely been recorded as a host of the common cuckoo, a widespread European brood parasite. The goldcrest is a host of the widespread moorhen flea, Dasypsyllus gallinulae, and of the louse Philopterus reguli. The amblycerous mite Ricinus frenatus has been found on the eastern goldcrest subspecies, R. r. japonensis in Japan, and at the other end of the range in birds of the nominate subspecies on the Faroes and in Spain. These lice move over the host's body, and have strong mouthparts that pierce the host's skin so that they can feed on blood, and sometimes feather material. A number of feather mites have been recorded in the genus Regulus; these mites live on fungi growing on the feathers. The fungi found on the plumage may feed on the keratin of the outer feathers or on feather oil. Status The goldcrest has a large range, estimated at 13.2 million km2 (5.1 million mi2) and a total population estimated at 80–200 million individuals, and it is therefore classed as least concern on the IUCN Red List. There was some northward range expansion in Scotland, Belgium, Norway, and Finland during the 20th century, assisted by the spread of conifer plantations. The population is currently stable, although there may be temporary marked declines in harsh winters. Although dense conifer growth can provide shelter for roosting at night, losses in hard winters can be heavy. In a Finnish study, only one-tenth of the wintering goldcrest population, which mainly fed on spiders, survived to spring. Each group roamed within a defined winter territory, and their winter survival depended on the density of the food supply. For these northern birds there is a trade off between staying put and risking starvation, or facing the perils of migration. Even in somewhat milder regions, where over-wintering is normal, exceptionally cold winters can cause such heavy losses that breeding populations take several years to recover. In 1930, the English ornithologist Thomas Coward wrote: Until the severe winter of 1916–17 the Goldcrest