I have heard it estimated that on certain BC rivers, some steelhead are caught as many as 3-4 times before the anglers go away and leave them to do their things over the winter.

This was a little shocking/disturbing to me as I had always liked the idea of a solitary C & R experience for a certain (smallish) percentage of the fish headed towards the gravel. As it turns out, on some of these systems with smaller runs of aggressive fish, a very high percentage of the run gets caught, many of them multiple times. However, I don't think this scenario is particularly relevant to winter run fish in the northwest where I would think a small number of the total get caught and those that do typically get caught once. If they are well handled, the mortality rate is well known and acceptable for most conservation minded anglers.