A great way to tame these early if you have a megalodon is to get the trap you have chosen and load it into the megalodon(you may need to upgrade weight some) then get the trap set up and take your megalodon and get some prime fish meat. Where nice you have done this keep the meat in your megalodon because it lasts longer in tames. Then trap the spino and knock it out and feed it the prime fish meat. I would encourage the use of prime fish meat to normal prime meat because it is slightly more and effective ad with the proper setup easier to get.