Cardinals not allowed

The lovely Mrs. Jib and I have a bird feeder on our deck. It came with the house, and I was never all that crazy about it. Last year we did not fill it at all, but because I knew that my wife wanted to use it, I've been putting food in it this summer. At first I used a cheap seed, and all it really attracted was sparrows and morning doves. A couple of weeks ago I put in a higher quality seed mix, and my deck has turned into Noah's Ark. The sparrows, morning doves, squirrels, gophers, and a couple of birds species I haven't identified are happily cohabitating and eating together on my deck. Except the neighborhood cardinals, my favorite birds, that is. We have two pairs of cardinals that I know of in the neighborhood, and they have not taken part in the feeding frenzy. This morning I watched out the door to my deck as all of these animals ate together, and then a male cardinal joined the group. That lasted about 5 seconds. Once the sparrows figured out he was there, they promptly chased him off. Apparently, the gray, brown, black, and white creatures don't look kindly on bright plummage.