Continuity mistake: When Theo hits the fence it becomes snapped a bit but in the next shot you can see him preparing to charge at the fence again, and it is whole again.
Continuity mistake: When Nigel is in the swamp in a dingy looking for a Deinosuchus, watch Nigel's sandals. Every time the camera faces a different angle, his sandals are either on (absent in the previous scene) or disappear (if previously on his feet).
Factual error: When Nigel is in the gyrocopter thing and is over the sea/ocean, you can see off into the distance an island with what appears to be houses, but it is supposed to be prehistoric times.