Harming Species

Key Takeaways

• Repeal would strip protection from 42% of habitat patches.
• One quarter of species could lose 95% of protection.
• Seventeen states would retain less than 25% habitat safeguards.
• State laws often unenforced, reducing real-world species protection.
• Federal agencies may expand development on public lands.

Summary

The Trump administration has proposed repealing the Endangered Species Act’s definition of “harm,” effectively removing the federal prohibition on habitat destruction for listed species. A recent study by Berry Brosi and colleagues shows that 42.4% of known habitat patches for ESA‑listed animals would lose protection, with a quarter of species facing a loss of 95% or more. Protection gaps vary widely by state, and in 17 states the average protected habitat would fall below 25%. The analysis warns that the change could be devastating for U.S. biodiversity.

Pulse Analysis

The Endangered Species Act (ESA) has long served as the cornerstone of U.S. wildlife conservation, linking the concept of “take” to habitat destruction through its definition of “harm.” By targeting this definition, the Trump administration aims to loosen regulatory constraints on private landowners and federal agencies, potentially opening millions of acres to development, mining, and other extractive activities. Industry groups argue this will spur economic growth, but conservationists warn that the legal safety net that once prevented irreversible ecosystem damage could evaporate.

A recent quantitative assessment by Berry Brosi and co‑authors provides a stark illustration of the policy’s fallout. Using 2018 habitat data for all ESA‑listed animal species, the researchers found that 42.4% of occupied patches would lose federal protection if the “harm” definition were repealed. Even more alarming, 25% of species would see 95% or more of their habitats exposed to unregulated alteration. The impact is uneven across the map: seventeen states would see average protection dip below a quarter of existing habitat, highlighting regional vulnerabilities where state statutes are weak or poorly enforced.

Beyond the immediate ecological consequences, the proposed rollback signals a broader shift in U.S. environmental governance. Weakening federal oversight could embolden state legislatures to pass even less stringent wildlife laws, while agencies like the U.S. Fish and Wildlife Service may face reduced authority to halt projects that threaten critical habitats. Stakeholders—from developers to NGOs—must now navigate a more fragmented regulatory landscape, making strategic litigation and policy advocacy essential to preserve the remaining safeguards for America’s most imperiled species.