The adult male siskin has a bright yellow face with olive cheeks and a black cap; its wings are predominantly black with a bright yellow wing-band which stands out amongst the black. The tips of its tail are black which fade to an olive colour before becoming a bright yellow on the male's back.
Female siskins are greener in colour and don't have the black cap exhibited by the male. They have a more mottled appearance with streaks on their tops and bottoms. Juvenile siskins have the same general appearance as that of the females but are brown in colour and look even more mottled.
Siskins are seed eaters, extracting seed from pine cones, birch and alder, only usually visiting Gardens for Niger Seed or Sunflower Hearts when natural food is scarce