I had a primitive bow and 47 tranq arrows in a swamp, and I had found a herd of there buggers. I picked a level 10 and ran around shooting it. I chased it around the swamp for a while(it was REALLY hard to dodge the kaprosuchus) and FINALLY knocked it out. After that, I shoved some mejoberrys down its throat and waited... Waited... WAITED for like half an hour until... BAM TAME.

I was level 32