If you think about where owls are hunting, the natural conditions they face, the Blakiston’s reliance on vision and the great gray owl’s reliance on hearing make sense, says Jonathan Slaght. Great gray owls hunt where it’s flat, with snow and quiet. Fish owls regularly hunt in narrow river valleys, with shallow, fast-flowing, and rocky waterways. “If a fish owl had hypersensitive hearing and hunted in these waterways, it would go crazy,” he says.