Too much intermingling puts native trout in trouble
Mixing with introduced rainbow trout could reduce offspring for the troubled westslope cutthroat
By Susan Milius
Even a little hybridization may hurt native cutthroat trout, suggests an unusual study of wild fish genetics.
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Trout are none too precise in their mating habits, and natives often make viable babies upon encountering certain other trout species.
Rainbow trout, beloved for sports fishing, have been introduced widely into new waters, and biologists worry that the mixing of the rainbows’ genes into native trout populations will undermine the natives’ long-standing adaptations to local conditions.