With a taming raft they are extremely easy to knock out but take quite a few tranq arrows in comparison to other dinosaurs their size. They have a fairly long range with their tail and can inflict devastating damage if they hit you or your boat. I generally use a slingshot or the first tranq Arrow to get its attention and since they're so slow you can easily cut it backwards wherever you needed to go. It will lose interest if you get too far away from it so try to stay fairly close.
1. Get tranq arrows and a crossbow
2. Find an anky of your desire
3. Shoot it in the head while walking backwards (they're slow so you can just walk while shooting)
4. When it runs away chase after it and shoot it
5. It'll be knocked out.
6. Feed it recommend food and any narcos if needed.
They get about 3x more metal than you! And depending on the level they can easily kill Raptors and other small predators.
They're found almost everywhere
Beaches, highlands, chalk hills, green forest, I've even see some near desert.