Endangered Species Act: A Hidden Driver of America's Housing Crisis

New economic research reveals a surprising link between federal wildlife protections and the affordability crisis gripping American cities. The Endangered Species Act (ESA), designed to protect threatened animals, may have inadvertently reduced housing permits by roughly 10% annually, contributing to higher prices and constrained supply.

Economist Maxwell Tabarrok of George Mason University published a study in the Journal of Public Economics quantifying the impact of species listings on housing development. His analysis of permit data from 1980 to 2024 shows that when a species is listed as endangered, building projects in affected areas face significant hurdles, from costly modifications to outright cancellations.

How the ESA Constrains Housing Development

The ESA makes it illegal to harm or harass listed species, a provision that extends beyond direct habitat destruction. Light pollution and stormwater runoff can also trigger compliance requirements. Developers in areas with endangered species may need to redesign projects, delay construction, or abandon plans entirely.

Tabarrok's research suggests that species listings reduce annual permit flows by about 10% of the average. Cumulatively, this translates to roughly 9 million housing permits affected since 1980, with most of those projects lost rather than relocated. The economist estimates this has reduced America's total housing stock by approximately 4%.

The Expanding Reach of Endangered Species Listings

The scope of the ESA has grown dramatically since its passage in 1973. In 1970, only 82 species were listed as endangered. By 1990, that number approached 500. Today, nearly 1,500 species receive federal protection.

Endangered species habitats now blanket most of the United States, with significant overlap in California and Florida. This widespread coverage means the law's impact on development is felt across the country, not just in isolated pockets of wilderness.

Natural Experiments in Housing Policy

Tabarrok leveraged the geographic variation in species listings to create natural experiments. When a new listing affects some regions but not others, researchers can compare permitting trends between affected and unaffected areas. His multiple analytical approaches yielded consistent results.

The study also found that proposed listings with no enforcement power have no effect on permits, while de-listing a species reverses the impact. Notably, satellite data revealed similar effects on both greenfield projects (undeveloped land) and infill projects (already-developed areas), suggesting that legal compliance, rather than actual ecological impact, drives the constraint.

Balancing Conservation and Housing Needs

The research highlights a genuine tension between environmental protection and housing affordability. While preserving biodiversity remains a legitimate policy goal, the current implementation may be creating unintended economic consequences.

For policymakers, the findings suggest a need for more nuanced approaches that weigh ecological benefits against social costs. Streamlining the listing process, focusing on the most critical habitats, or implementing mitigation banking could help balance these competing priorities.

What This Means for Global Housing Markets

While the study focuses on the United States, its implications extend internationally. Countries with similar environmental regulations may face comparable trade-offs between conservation and development. Namibia, with its rich biodiversity and growing urban centers, could learn from these findings when designing its own environmental and housing policies.

As cities worldwide grapple with housing affordability, understanding the full range of factors constraining supply becomes increasingly important. This research adds a critical piece to that puzzle, demonstrating that well-intentioned regulations can have far-reaching economic consequences.

Robert VerBruggen is a senior fellow at the Manhattan Institute. This article was adapted from City Journal on Substack.