It would be nice to add a countdown when there’s left less than 5 minutes till despawn. Few times I was walking to a rare dino without any hurry and it despawned right in front of me. Yesterday it was tyranosaur that despawns 100 meters from me. If I saw that it’s left few minutes to stay, I would go faster or run to it and I could catch it.
It can be added to the screen where there’s “launch” button and big image of dino. It would show how far from you the dino is and how much time it’s left to stay.