These all feel a little grey and cool to me. Were these shot on a cloudy day? The birds are quite nice. Try a little more exposure for them, they can handle it and you might bring out a little more detail and get a little more life in the eyes (although bird's eyes are always gonna look a bit like hard little marbles of evil).
You might try warming the colors up a little and pushing the contrast up a hair. You might like the result.