Combat xp works like all other combat/weapons xp. So if you are too high a level for you to trap equal level animals with your low trapping xp, you won't get but 1-2 points per animal trapped and killed. They should make it where trapping xp is based off your trapping lvl not your combat lvl, but they didn't plan this thing out to good. So sucks to be you, nothing personal, but it does. I used my last respect to max out trapping so I wouldn't have to get to master ranger 1 trapping xp at a time. Imagine having to kill about 3 million critters to have a shot at master ranger. What a waste of time. Good luck, man. Cause SOE don't care. I suggest, if they are all only getting 1-2 xp regardless of lvl, then find critters you can kill in one hit. At least then you can kill them faster. If you are on starsider, let me know what kind of traps you can currently use and I'll crank you some out. Good luck.
-Al