Hi Roger,
Part of the process of being a good photographer is managing where a viewer’s eyes are going to look within your photograph, and often that means eliminating highlights while pulling important details from the shadows.
As I look at these two Galahs my eyes want to go immediately to that bright highlight in the lower right of the picture, and then across to the bamboo that appears rather brightly behind these two birds. It is only after my eyes have had a wander about this area that I start to pay attention to the birds.
The bird on the right is easy to discern, but the bird on the left is lost in shadows… it is rather difficult to see its eye and so all that we really notice is the mop of feathers on top of its head.
To improve this picture I think it would be worthwhile to crop in tight on these birds. It will eliminate the highlight in the lower right but and make a statement to the viewer: “This is what I want you too look at”.
In the example below I used Photoshop's Burn tool (with range set to Highlights) to darken the bamboo down to a softer midtone.
Finally, I used the Lasso tool with the feathering set to about 20 pixels to select the face of the bird on the left, then used Curves (move the middle of the curve) to make the face brighter.
Do this with the high-res version and I think you will have a nice portrait of these two love birds.
Cheers, Anthony
Image Doctor's edited version