Dena,
>"5' from the center of a trail is crazy, I'm shocked that's legal. "
I'm with you on that, but I suspected it was perfectly legal in Alaska. It certainly happens a lot on the Kenai.
I just read through the Alaska trapping requirements and while there is a request to "Act responsibly as a trapper and conservationist by trapping in ways to minimize conflict between trapping and other users, e.g., avoid high recreational use areas. Avoid situations where you might catch a domestic dog or cat, such as near homes or trails frequently used by hikers, skijorers, dog mushers, or other people.", there is not a requirement to do so.
>Even a wandering child (stepping off the trail to go to the bathroom, for instance)"
or a child who goes to investigate why that bird wing is hanging from a tree branch, within reach.
It is actually illegal to REMOVE such traps from public lands.
Trappers are not without ANY constraints. For instance, one may not:
"take furbearers with the use or aid of a machine gun, set gun, or a shotgun larger than 10 gauge"