Darts work best. Best to put it in trap and wait before each hit so torpor rises. It’s so easy to accidentally kill these things during knock out. Also bring a couple hundred narcotics and biotoxin. They drain torpor so fast.
To tame one of these just clear out an area of all other creatures. Then eat a rare flower so it will agro you. Shoot it with a few darts and boom it’s nocked out. Make sure you have lots of narcotics though.