Well, not quite as long as your arm.

A friend of mine did his Masters Thesis on the fish populations of Chester Morse Lake. It contains lots of native Dolly Varden (bull trout nowadays?) and rainbow trout. As part of his research, he had to sample the fish - poor guy. As I recall his stories, the fish averaged more like 16", with some larger of course, and some smaller. They are abundant, and because they are not fished on, quite dumb, and they came to any small spinner, spoon, or streamer fly. Yeah, it would be cool to fish there, but it is very closely patrolled by Seattle City Water Department, and they don't mess around with tresspassers, apparently.

Sincerely,

Salmo g.