10/10/2024
European Siskin/Grönsiska (Spinus spinus)
Siskins Siskins everywhere!!
With the big groups of European Siskins (Spinus spinus) moving South to spend the winter in warmer places, we are having some of them in the nets at the Lighthouse Garden!
These little green birds show differences in the plumage between ages and sexes as you can see in the pictures. First, females show greyer colours than the stronger green, yellow and dark tones in the males. Second, coloration in juveniles – both males and females – tend to be duller, not showing as much contrasting colours as adults.
This species just moults once a year, during summertime. Juvenile individuals will do a partial moult while adults will do a complete moult. Therefore, now, in autumn a moult limit can be found in juveniles, as shown in the open wing pictures.
But then… If they do not change their plumage before spring, why do we see individuals with completely black caps? Do you remember the last video posted, the one shared by .ecology about the Common Starling/Stare (Sturnus vulgaris) and their white dots? As for the Starling, and many other birds, feather wear will lead to the full spring plumage in Siskins. If you look at the last picture you will see two birds in different seasons, a male siskin in spring and a male in autumn. It really looks like the bird in spring has a new plumage, more green, more black and more yellow… but it is the same!! It just lost the greyish edges in the feathers of the cap and… actually, the entire body!! In other words, during the months following the autumn, siskins will wear off their feathers and will slowly lose the grey edges.
