It’s not often that ST readers get the chance to contribute to scientific research. However, learning to age woodcock by examining their wing feathers is one way we can help to learn more about the population trends of this elusive migratory bird. Features of particular sets of these feathers give an accurate method for ageing. Once you can identify these different feather groups you can start learning how to age the bird from which they were taken. It’s important to collect wings from adult and juvenile birds until you can spot the differences. Check all the groups of feathers rather than just one in order to confirm your results.
Examining the upper wing feathers
On the upper wing the feathers are:
Primaries ? the 10 long flight feathers numbered 1-10 from the wing tip.
Secondaries ? the large feathers on the inside of the wing leading off from the primaries.
Primary Coverts ? the groups of medium-sized feathers that overlap the top of each of the primary feathers.
Secondary/Great Coverts ? the group of medium-sized feathers that overlap the secondary feathers.
Alula ? these are found on the upper wing about halfway along and overlap each other and the primary coverts in a line towards the wing tip.
Primary feather Tips
In their first winter, juvenile woodcock will still have the same feathers they fledged with. They will not have moulted since birth. These juveniles could have hatched in late March through to August broods. As a result, their feathers and especially the tips have undergone some wear by the time we encounter them in October and November. This is most apparent on the tips of the three outer primary feathers. In juvenile birds, the tips are worn, ragged and in severe cases look moth-eaten. On an adult bird’s wing, the outer primary feather tips are distinctly clean-edged and exhibit a sharper, neater profile as they have recently moulted. These are best viewed held up against the light.
Primary Feathers 4-10
The trailing edge of the primary feathers 4-10 on a juvenile bird tend to have a rounded profile and give the wing a scalloped appearance. By contrast, those of an adult bird show a straighter profile and the trailing edge of primaries 4-10 appears as a near-straight line. The outermost primary feather, the tip feather, is number 1. Simply count in to number 4 and examine up to number 10.
Primary Feathers 4-10
The tip of a juvenile primary feather 4-10 shows a rounded even edge while that of an adult is notched or stepped.
The alula feathers on juvenile birds have a more rounded tip. In addition to this they are also paler and the patterning is less defined. For the adults the alula feathers have a pointed tip with a stronger patterning and a much darker colouration.
The tip of a juvenile primary covert is narrower than that of an adult. However, the most distinctive difference is the pale band at the tip of an adult’s feather. On a juvenile, the band at the tip is darker and in keeping with the colouration of the covert feather. That is, of a brown to light-brown shade. On an adult
feather the band is pale and leans towards light-buff or white.