This is a cross between a female brown trout (Salmo trutta) and a male brook trout (Salvelinus fontinalis). It is primarily an artificial cross, though it has been known to occur in nature. Because of genetic differences between the two genera (the brook trout is actually a char), mortality of the eggs and alevin is high. About 65% of hatchery specimens do not survive and the loss is higher in the wild where the majority of normal eggs and alevin perish due to predation. Hybrid specimens that survive are unable to reproduce. They have primarily been produced only on a small...