Getting to the point where a cause goes from being a terribly daunting task with a handful of adherents to an acknowledged success with momentum and many allies is a rarity.
If you want psychic gratification, one of the greatest ways is to know that you've made a real contribution to saving a species from blinking out during your lifetime.
People need to look at wildlife conservation in its totality. As soon as you lose the apex predator, it has harmful consequences right down the food chain.