Bring a raft with either an argentavis or quetzal, go to the most north west part of the map, dive down and keep going into the water for about 10 seconds or so then come up. The birds can be used for carrying/ ir maximing the timee for the meat that it will need!
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.