Greenfinches are the biggest finches Europe; they are yellow-greenish and have a strong beak and a strong body build. Regardless of their somewhat stubby body, they move in a skilled manner, and are very fast flyers. They feed on a wide variety of seeds and in winter, they are glad to see feeding houses. Their song consists mainly of calls, which alternate with delicate whistle-like, gurgly voices. They prefer to nest in spruces. The female bird builds the nest. The outside of their nest consists of dry grass, leafless twigs, moss, and lichen; the inside, however, contains wool and hair. The form and building type of the nest are similar to the nest of a chaffinch; the outer finish, however, is not as remarkable. Their eggs are bluish to whitish, with light and dark brown spots and flecks. Their chicks do not leave the nest before they are about two weeks old. Both parents feed the chicks. In the event of a disturbance, greenfinches behave fairly calmly near the nest. Sometimes, however, the female bird jumps off the nest and slowly moves away from it, while pretending to be injured, to distract the trespasser and make them retreat from the nest.