We normally refer to these fish as boots because they get to be the color of an old boot. They have a leathery appearance after they have been in the stream for a long time. Even the color of the meat changes. For years I never kept a boot just because they are so ugly looking when they get to this stage. My Son caught one several years ago and decided to keep it for table fare. The flesh was almost white unlike the normal pink flesh that they normally have. We did eat it and it didn't taste half bad.