How do I ensure capture of Ancient Danger Cyropods?

[Draconzis Piertii]

I distinctly remember reading somewhere online that I can practically ensure the capture of all pawns that spawn from the Ancient Cryopods. I think it might have been by sealing off the entrance after awakening and waiting for them to fall from malnutrition. However, I'm not 100% sure and a quick Google search only seems to come up with guides to kill the mechanoids and/or lethally deal with the cryosleep pawns. Does anyone know for sure?

[sbmarauderman03]

Even if you 'seal' off the pawns, they will attack walls/doors to get out. Best thing to do is make the Ancient Danger back into a room/building, slap down a bunch of sleeping spot and change them to prisoner only, then arrest the pawns.