One thing to keep in mind when taming these bad guys.

NEVER get close to them unless knocked out.

Tranq arrows/darts with them. You might have to use narcotics. Also, keep in mind these bad guys only eat fish meat. Knock it out in a place where the two of you will be safe. After tamed, he becomes a very agile and strong mount, overall a weaker Spino with better agility.