Hidden Fatigue (not surplus)
Aside from Surplus, I've found that there is another (hidden) fatigue for fishing. It affects you by limiting your catches. If you get a fish to bite, and you hook it, your remainder meter will drop to 0 and you will lose the fish. Also, you receive more "Nothing Bites" messages. I noticed this fatigue after 6 hrs of spearfishing, then going to fish afterward (in other words, it doesn't seem to affect spearfishing, but can be brought on from too much spearfishing or regular fishing). Also, I did not have Surplus. I have read a few sources that say that this also can affect the other gathering classes, but I'm not too sure about that. I was going bonkers trying to figure out wth was going on, then I remembered the fatigue system from FFXI and this kind of reminded me of it.
So fellow fishermen/women, have you found this to be true for you as well?