Not uncommon to see steelhead caught more than once. Over the years when tagging fish or taking scale samples have caught the same fish not only twice in one day but on three occassions caught the same fish on consective casts. Not sure whether those fish were super biters or just plain dumb! Seem to recall that one tagged fish was caught 8 times in a 3 month period.
Bob and Todd are correct in that most repeat spawners are females. The males linger near spawning areas (likely mother natures way of insuring that any late spawning females will have males to mate with her). Have seen winter males (spawn-out) in the river as late as the end of October. However males can survive a spawn multiple times. The males are probably less than half as likely to survive as the females though that ratio varies considerably year to year with higher survival rates happening when there are higher river flows during and after the spawning season.
The life history of the a fish can make a big difference in the size of the fish. Remember in 1983 the Sauk broodstock program had 3 fish that were 7 years old (very rare animals). One male was a 2.4+ (2 year smolt and returning to spawn for the first time after 5 summers of ocean rearing). He was 43.5" and weighted 31.5#. Another male was a 3.2+s+ (a 3 year smolt, 3 summers of ocean rearing before returning to spawn and returning for the second time). He weighted 16.5#. The third fish was a female whose age was 2.2+s+s+ (2 year smolt who returned the first time after 3 summers of ocean rearing and was on her third spawning trip). She weighted just over 20#. Quite a sizxe range for fish of the same age.
I have noticed over the years that those males with what I call alligator heads are generally repeat spawners. By an alligator head I mean those with a head than looks larger then normal (a head of a 18#er on a 14# fish for example). They also tend to have larger jaws. I bet Bob knows exactly the kind of fish I'm talking about.
Tight lines
Smalma