I can't remember where I saw the study...I know someone posted it on here!
But if I remember correctly, they can see an even greater spectrum than we can.
Yes, like other birds, they can see colors, in fact they can even see ultraviolet which we can't. A lot of wild bird species have plumage with ultraviolet colors to attract mates. These colors we of course can't see.
I didn't check the link, but I can tell you they can spot a ripe tomato amongst the foliage and green tomatos and attack it! Not touching the green stuff once. Sounds like seeing color to me!