If knocking out with tranq arrows use narc traps but don’t use them to knock it out if you knock out a creature with narc traps you can’t access their inventory so use the final shot with a tranq arrow
Direbear have little health compared to torpor. Keep a few tamed dodos at your ramp trap. When you've shot the bear enough for it to be bloody, throw in a dodo. It will instantly kill and eat it and start regenerating health. Give it a moment or two and continue darting. Happy hunting!