Keystone Conservation is a nice web site that provides information on keystone species and their critical role in our ecosystems. They focus on “Pioneering Solutions that Help People and Predators Coexist.”
What are Keystone Species?
The keystone at the top of an arch holds all the stones in place. Without it, the arch collapses. Healthy ecosystems needs keystones—like wolves and whitebark pines—to function. Keystone species are the architects of biodiversity.
Many predators are keystone species. We focus on far ranging species like wolves and bears in recognition of the complex, interactive, and vital roles these species play in predator-prey dynamics.