Or you might be hunting in a place like Tanzania! Or at least I've heard that can happen as the government will chage prices on a whim....
Bluey I agree with you on hunts booked. If both client and outfitter took a chance on the exchange rate and it changed, so be it... Both ways. On the other hand I was billed in Rand on the final settlement on one of my hunts... And the exchange rate wobbled around a bit from the time it was checked to the time it was charged to the credit card. Just the little daily fluctuation. But I was given such a good deal to begin with that there were no worries... However I could see how someone else could get upset over that... So I think when outfitters quote in USD, they ought to settle up that way to avoid any potential misunderstandings.
However, I did not take the OP to mean to re-negotiate agreed upon deals... But rather that if booking a hunt today based on prices perhaps set last January... There might be a bit of room to negotiate.
Another important point is that this has the potential to make Africa a better deal again. I've had outfitters tell me they expect 7% increases in prices per year... With Inflation in the US running closer 3 or 4%, Africa will eventually price itself out of business if that continues... But the changes in exchange rates are a natural way of balancing this out. When one country experiences higher inflation than the other, their money simply becomes worth less. Just look at Zimbabwe... out of control inflation lead to their money being worth less than the paper it was printed on.
So the answer to the OP is YES, outfitters should be expected to adjust pricing (when quoted in USD) on future contracts. And I think the other point made, if your already booked for a basic package, you might be able to expect some very good offers on extras, like additional animals.