Hmm. A lot of holes shot through my theory. All I can say is that there is a lot of carotene in shrimp--krill being a plankton-sized form of shrimp--as well as freshwater shrimp like scuds. Certainly, I've seen that Lone Lake, which has lots of chironomids, does produce trout with colored flesh, as well as deep red stripes. Whether or not it also has scuds is something I cannot attest to. Beyond this, I have to admit that I must defer to a marine biologist for a definitive answer. Still, wouldn't you think that the hatcheries' use of shrimp shells to deepen the color of their trout would be some proof of the role of carotene in the color of salmonids' flesh?