Common Crossbill of Britain and Ireland
The Common Crossbill, Loxia curvirostra, is a large, stocky finch who is either a resident bird or occasional breeder in Britain and Ireland.
Crossbills are nomadic birds who roam over woods and forests in search of the seeds of pine cones. The seeds of the Norway Spruce are particularly favoured. Large flocks from Europe occasionally arrive in Britain and Ireland in search of seeds from the Norway Spruce. Some stay and breed before returning to Europe.
The population of Common Crossbills is difficult to assess in Britain and Ireland due to the highly mobile nature of these birds. They are sometimes known as the Red Crossbill.
Males are normally red although some have orange or yellow plumage. Females are greenish-grey and juveniles are pale brown.
Crossbills travel in large, noisy flocks or small family groups for most of the year. They are normally seen flying near the tops of trees in woods and forests.
The most distinguishing feature of these birds is a large bill which is crossed over at the tips. The bill is specially designed to prize open and eat the seeds of pine and conifer, particularly those of the Norway Spruce, Scots Pine and larch.
The Norway Spruce is the favoured tree of Crossbills because the seeds are larger and produced in greater quantities. Crossbills seek out the seeds of the Norway Spruce in commercial plantations, large forests, woods and occasionally parks.
“.This accomplished acrobat will hang upside-down, cracking open a cone kept pressed against the branch. The bird can carry cones as heavy as itself. It can strip bark from trees to expose creepy-crawlies underneath and chop up apples” (Irish Examiner -
The leaves, shoots and seeds of low lying plants, insects and invertebrates are also eaten.
They often fly down to the ground and drink from pools, rivers and streams.
Common Crossbills are widespread birds in Britain and Ireland where there is suitable habitat. Resident Crossbills often leave their woodland homes and fly to woods and forests where there is a good crop of pine cones.
They are mobile birds who either remain in Britain and Ireland or fly to Europe in search of food.
Established breeding areas in Britain include the Scottish Highlands, the North Norfolk coast, the New Forest and the Forest of Dean.
Crossbills from Continental Europe often fly to Britain and Ireland between May and June.
Irruptions of Crossbills from Scandinavia and European Russia occur at intervals of between 1 and 11 years. The irruptions happen because the Norway Spruce fails to produce a sufficient crop of pine cones.
Thousands of birds arrive on the shores of Britain and Ireland as they move southwards and westwards. Most are found on the east coast. A large proportion of European Crossbills stay and breed before they and their offspring return to home
Crossbills are able to breed throughout the year although the time when nests are made depends on the number of pine cones available.
British and Irish Crossbills normally begin nesting in February and continue to raise their chicks through the spring. Some pairs begin nesting in August and rear their broods during the winter months.
The female builds a nest high in a tree which is made of twigs lined with finer material such as moss and feathers.
Three to four eggs are laid which take 2 weeks to hatch. The young are cared for by both parents and leave the nest after between 20 and 25 days. Pairs continue to feed their young for another 3 and 6 weeks.
The Common Crossbill is classified as of Least Concern by IUCN.
Europe holds about 20% of the global population of Common Crossbills. The population is described as “fluctuating” by Birdlife International. For example, a decline was reported in Finland because of forest fragmentation.
The Common Crossbill is a green-listed species of bird in Britain and Ireland.
The British Trust for Ornithology said the population is “difficult to assess” because of the mobile nature of these birds (BTO - https://app.bto.org/birdtrends/species.jsp?year=2011&s=cross ).
The range of the Common Crossbill has increased in areas such as Scotland and Ireland because of the planting of conifer forests.
The main threats to Crossbills include the felling of pine and conifer trees in woods and forests as well as predators such as squirrels.
For more information on the birds of the gardens and countryside of Britain and Ireland, please visit,
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