Tame a doedic pump weight then set it on wandering and pick it up with a argy and fly next to a rock and it’ll collect stone. Since the doedic has a weight reduction you should just leave it in his inventory.
The Doedic is one of the most essential Dino's on ark. It's the most important thing when building stone buildings, or other stone structures. The higher the level the better, and weight is essential!