To achieve the stated objectives and goals, optimization tools (e.g. Marxan) are used to prioritize assessment units. This creates a transparent, flexible, and credible decision support system where multiple scenarios can be explored.
Useful rules of thumb for site selection:
- The results from any site selection tool provide guidance and decision support, but they should never be assumed to provide final answers.
- As with all models, poor input = poor output.
- Start with simple site selection scenarios and establish sensitivity analyses (e.g. variations of input parameters such as goals) as the planning process advances.
- Site selection should often place greater emphasis on results from the most reliable data. For example the data on near-shore targets may be better and more reliable than offshore targets and these former data may be run preferentially.
- The tool outputs should be peer reviewed and adapted.
- Change results when credible ecological reasons can be recorded and included in the final plan. It is common on review for sensible changes to be offered and these need to be documented.
Case Study: Carolinian Ecoregion
In the Carolinian ecoregion, Marxan was used to identify efficient solutions that met conservation goals for all targets (left map); these results were evaluated and modified in expert workshops (right map).