What’s going on here?

I caught this guy on the Big Wood recently, and it’s unlike any whitefish I’ve seen. It had such a brilliant pink coloring. The spots on the gill plate and at the base of the fins were so blood red I thought I had gilled it. I’ve caught more whitefish than I can count, but never seen one colored like that. The pictures really don’t do it justice. While it was in the water I thought it was the most colorful trout I’d ever seen until I saw it close up and realized what it actually was. Any idea why it’s so differently colored? The thing basically glowed pink in the water.