Reed F. Noss and Allen Y. Cooperrider in Saving Nature’s Legacy: Protecting and Restoring Biodiversity (Island Press, Washington, D.C., 1994)
Noss & Cooperrider reviewed many conservation planning initiatives and determined that between 25% and 75% protection was necessary to maintain ecological integrity.
Written by two leading conservation biologists, Saving Nature’s Legacy is a thorough and readable introduction to issues of land management and conservation biology. It presents a broad, land-based approach to biodiversity conservation in the United States, with the authors succinctly translating principles, techniques, and findings of the ecological sciences into an accessible and practical plan for action.
After laying the groundwork for biodiversity conservation – what biodiversity is, why it is important, its status in North America – Noss and Cooperrider consider the strengths and limitations of past and current approaches to land management. They then present the framework for a bold new strategy, with explicit guidelines on:

• Inventorying biodiversity

• Selecting areas for protection

• Designing regional and continental reserve networks

• Establishing monitoring programs

• Setting priorities for getting the job done

Throughout the volume, the authors provide in-depth assessments of what must be done to protect and restore the full spectrum of native biodiversity to the North American continent.
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