Bull trout are an increasingly rare char native to the pacific northwest and the hotbed of controversy in terms of ESA and habitat protection. I am not aware of artificial stocking of the bull trout on this side of the divide but I guess anything is possible.
My guess is that it was a tiger or brookie, since their coloration varies so profoundly. I've caught tigers that looked lavender all over and others that were slate grey like a laker. I've caught brookies that were almost silver throughout (albeit searun) while others were neon reds, blues and olives. Trout in general display a spectrum of color schemes even within strains depending on a large number of factors including spawning, diet, and environment.
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All photos courtesy Luis Nasim and Eugene Hoyano, All rights reserved</font><!--1--></center>