I have read comments that ichtys are being killed by other creatures. So you can take a bunch of these so they will attack the predator. Because after you tame they will attack if you whistle “attack”. Or you can place dinosaur gate.(these tips are for single player ark mobile). In multiplayer p v e mod you can place them near other players dinosaurs like the other players tamed mosasaur or megalodon,etc or you can use single player tips if you want to protect them yourself.