one there is already a limit of fish that can be taken, "3 per day" and a "two day possesion limit"
the second point is, depending on where you are fishing, the majority of fish in those rivers are planted from fisheries and are not born there. it is true they do return to where they were releassed from
also remember this, when there are several species of salmon spawning in the same areas, beds are distroyd before the previous runs' eggs has had a chance to hatch.
there is no doubt that it is disturbing to see, but when harvey comes by with the rest of the story, things that seem disturbing and apualing becomes aperent that all is right in the world.
You can bet on this, if it were a threat to the fishery the season would be closed during the spawning periods.
sounds like you could write a bit of an artical on the ethics of salmon fishing....
and by all means give it a go, I am sure others would like to read your views and compare notes...
Taking a female on a bed obviously has an effect on the population but in the larger scope of things probably isn't going to make a huge impact.
on the other hand....
Taking 2-3 females off the beds has a very LARGE effect on anyone else who would like to fish the area as well.
Sad thing is... the kids probably didn't even realize what they were doing and were just happy that they caught some fish.
Education is the only way. Next time stop them and tell them ...."the rest of the story" maybe next time things will be different.