Fisherman pulls trap toward surface. Crab: The G forces are incredible Crab 2: Yes, we could obtain escape velocity! Crab 3: I read about this in the latest Exoskeletonnnnnnnnnnnnnnnnnnnnnn!!!! Crabs exit liquid atmosphere.
That's why Funnel type entrances (like the kind in Crab Pots on the east coast) would have been more effective; they have no moving parts so that a there's no gate to swing open even if the pot was turned upside down.