A few questions:
Are you shooting raw or jpeg?
What software are you using for post-processing?
How much post processing do you do? What do you do in postprocessing?
What does your histogram look like?
This image does not look over saturated and I am not sure that there is a contrast issue with it either; however, it does look a bit underexposed because ti seems to be a bit on the dark side. It would appear that there are no shadows, so can I assume that this was an overcast day(?). Days like that will often produce "dull" images, because there is no sunlight to produce significant highlights or shadows, or provide the contrast you might like to have, particularly when the image is composed of a lot of components that are some shade of grey. This image does look a little fuzzy in places, almost like it was out of focus because the bird(s) moved a bit or it was a bit windy. Did you do any sharpening, because maybe this image could use a little sharpening. Not sure what else to suggest, because if it is out of focus, or fuzzy because the shutter speed was not fast enough, or the speed was low and camera shake got in the way, then these things can be fixed by increasing the shutter speed and/or find some way to reduce camera shake. I am just sort of stabbing in the dark, but these are the sort of questions I would ask myself if it were my image. HTH.
Cheers,
WesternGuy