Goldcrest

The Goldcrest is, along with its congener the Firecrest, one of the two smallest birds in Europe. They weigh only 5 to 5.5 grams. At first glance, they are tiny birds with a green appearance. To distinguish them, there is the song, which is the easiest, but this is only valid in spring. Otherwise, you have to look at the head. The most visible difference is on the side. The Firecrest has a black band around its eye, which is very visible against a white background, while the Goldcrest does not. Its dark eye circled with whitish gives it a kind of astonished look.
Like the other one, the crown has three longitudinal bands, a medium, wide, orange or yellow surrounded by two blacks. This is where the small sexual dimorphism is located. The middle band is yellow-orange in the male, yellow-lemon in the female. These colored feathers can be erected in a short crest when the bird is excited or anxious. The sides of the head and the nape are shaded with gray. The beak is black, thin and pointed.
The mantle and flight covers are olive green. The broad and round wings have two white wing bars. The primary feathers and rectrices are dark, edged with green, the first ones barred with black at their base. The tertiaries are tipped with white. The underside is beige to light chamois. The legs and fingers are light brown. The Goldcrest has strong fingers to grip the prickly branches of conifers.
The juvenile is similar to adults, but without the bands of the crown, which will only appear at the next post-juvenile molt, giving it an even more open face than that of adults.