Showing posts with label Little Eagle light phase. Show all posts
Showing posts with label Little Eagle light phase. Show all posts

Sunday, February 21, 2021

 Light and Dark

The Little Eagle juveniles in the Canberra area have all fledged and are now flying freely around their local patches. They are still dependent upon their parents to supply them for most of their food, although they are beginning to catch prey for themselves. Hence, it is a good time to catch and band them for later recognition. There are two colour morphs of the species, light and dark, and it is useful to hold these birds in the hand to see just how different they are from one another.  

              

The bird on the left above is a dark phase individual and the one on the right is a light phase. Although both these birds are juveniles and as such have typical red colouring, once they moult into adult plumage they will still retain the dark or light markings. In these examples, the dark bird is a male and the other a female, but the sexes can be either phase. And the female is actually larger than the male as is usually the case, but it is difficult to show this in photographs.

Both birds have individually numbered metal bands on their right leg and a unique coloured alpha-numeric metal band on their left, in these cases both are red. So if any readers see any Little Eagles, please check their legs for such bands and report their location to this study. The light bird has also been fitted with a GPS-satellite-tag on her back so that her movements can be followed.

The bands are red in the modern sense, the birds are red in the old sense, as in a red dog. A term that has been used since long before bright dyes have been used.

The dark birds have a smokey appearance which is created by the broad dark markings on the breast. The pale straw colouring of this bird's crown contrasts with his dark face.

The dark streaks on the pale bird's breast show as narrow lines and more red shows through. Her crown and nape have rich red colouring.

No matter whether light or dark phase, all Little Eagles have bright sharp eyes.