Length: 16.5 cm.
The female’s plumage is greenish.
Voice: Sounds resembling ‘chip chip chip’.
Song: Chattering, flute-like.
Size of Egg: 19.4—25.5 x 141—17.5 mm.
The crossbill, so named because of its distinctive bill, the tips of which are crossed, makes its home in coniferous, mostly spruce, forests in mountain areas, occasionally also in lowland country, in central Europe, Scotland, the Pyrenees, the Alps and Scandinavia.
It is a resident bird but frequently appears in places it has not visited for years. Northern populations sometimes invade southern Europe, depending on the abundance of cones, especially spruce and pine, in any particular year. The mainstay of its diet are the seeds of cones, which the crossbill extracts with its beak and which it also feeds to the young. It occasionally eats insects, mostly beetles found on conifers. It breeds mainly from January to April.
The nest is built by the female, without any help from the male, though he keeps her company during this period. The 4 eggs are usually incubated by the female for 14 to 15 days, during which time she is fed by the male with food from his crop. The nestlings are born with a straight bill, the tips becoming crossed only after they have reached the age of three weeks.
During the first week, the family is fed by the male, so that the hen may shelter the young from the cold. After two weeks the young leave the nest and roam the countryside in the company of their parents as they seek food. It was once believed that if a caged brick-red male turned yellow in captivity, he would cure the fever of sick member of the family. The fact is that the male’s colouration often becomes dulled in captivity.