Limited patterns among ESA 4(b)(2) critical habitat exclusions


Areas can be excluded from critical habitat (CH) designations for economic, national security, or other relevant reasons under 4(b)(2) of the U.S. Endangered Species Act (ESA). We are aware of no analyses that quantify the rates or patterns of use. To address this gap, we undertook a small descriptive study of CH 4(b)(2) exclusions. Less than half of designations in our sample had exclusions, most of which were classified under ‘other relevant factors’; all exclusions in our sample occurred in the past 20 years. While there was substantial variation, found no statistically significant taxonomic or regional differences in designation rates. These results can inform judgments if new 4(b)(2) exclusion regulations are proposed.

ESA 4(b)(2) critical habitat exclusions
Andrew Carter
Director, Conservation Policy

As a Senior Conservation Policy Analyst in the Center for Conservation Innovation at Defenders, Andrew researches and analyzes conservation governance strategies and emerging policy issues.