Taming is very easy, a lvl 21-ish got took down from the air with 2 tranq arrows, then I killed some Carnos for prime meat. Literally wasn't even a second and it was tamed. Gonna name her Freedom cuz shes just a big friendly eagle. Found in the snowy areas of The Island. Awesome tame to fly around with and kill Rex's, NEED TO HAVE HIGH STAMINA AND MELEE, YR BIRD MIGHT DIE IF U TRY THIS WITH LOW LVLS.
An argentavis can't fit through a ceiling with one tile missing, but a pteranadon or lymantria can. Build a trap with one corner ceiling missing, aggro the argentavis, fly in one side and out the missing ceiling tile, and land. Dismount, run around, and close the entry door. Tame safely at your leisure.