Based on the you tube videos and the expert authorities available it would reason that no defense weapon is needed. Why everyone on this sight has probably seen the pig hunting series on the Discovery Channel. They use no firearms period.
Therefore I would recommend packing a couple dogs on all hiking trips, and of course a length of rope and possibly a chain link pen. It's perfectly humane, eliminates the risk of being caught with a firearm in a restricted area, and lets face it, no worries of being arrested for poaching!