I have no DG experience, but hunting in New Zealand I carry maybe 25 rounds - ready for the worst case scenario... getting hurt and stuck somewhere. A rifle is a great survival tool, and shots are a great way to bring help to the right area.
With a PH you are probably not going to get lost and stuck somewhere, but I have met enough people attacked by various animals higher up the food chain to realise excrement can/does happen. And I hve also known some staff to take off and leave others in the lurch...