Use transponders. Trust me.
Tag one and tag your raft and you will not lose it no matter how far it swims. Use a basilo so squids and jellies dont get you. Take 2 scuba tanks at least and try with high damage xbow and about 200 tranqs. Use raw mutton and drive raft straight on top. Keep either a live sheep or refrigerated mutton or warp to bed from drop or obby with mutton on you. Ez tame. As easy as a giga if you do it this way.
Very easy to tame if you know what your doing. First tame an Ichthyosaur. Then grab a crossbow and some tranq arrows and find one and knock it out. It is not be able to attack if you are on the Ichthy. As you are taming it, be sure to remain on the Ichthy unless feeding narcs, so other creature don’t hurt you. Vote up if this helped
He will flee as soon as any torpor is dealt, which means you can trap him against a underwater cliff to tame him. He takes superior or snake kibble on mobile, and can break stone and gets tons of oil when tamed.