I think it can be a big help if the local population can see a tangible (economic) benefit in preserving wildlife/wilderness in their area. I remember on Ken Burn's national park series, the creation of many of the parks was vigorously resisted by local people at first, but years later most agree it to be one of the best things to happen in their area (Grand Teton is a good example).
I lived in Nepal for a year and the trekking / adventure sports industry is a huge income producer; many people have jobs as guides / porters / restaraunt & hotel operrators, etc. In fairness, the areas that are not popular for these activities have a harsh living standard, as Crockett described.
I got into flyfishing about 4 years ago and there seem to be a lot of fishermen now interested in catching native trout, rather than just the largest stocked rainbows they can hook. There is thus a real effort to restore species such as Greenback, Westslope, and Rio Grande Cutthroat to their native waters.