For decades, federal rules said significant habitat destruction could count as “harm” when it actually killed or injured protected wildlife. A rule finalized in July 2026 deletes that definition, narrowing a key protection for animals and the places they need to survive.
This explorer brings together 1,643 distinct species represented in current U.S. Endangered Species Act listings: 1,594 from Fish & Wildlife Service data and 49 marine species managed by NOAA Fisheries.2
The rule examined here concerns the ESA's prohibition on the “take” of fish and wildlife, so its direct effect falls on the animals in this collection.
The ESA makes it illegal to “take” endangered wildlife, and similar protections apply to many threatened animals.
For decades, federal regulations interpreted “harm,” one form of prohibited “take,” to include significant habitat modification when it actually killed or injured wildlife. NOAA adopted a similar definition in 1999.1
The new rule removes that definition. Under the agencies’ new reading, destroying habitat does not count as “take” unless the action is directed at the animal itself.
Significant habitat modification or degradation can count as “harm” when it actually kills or injures wildlife by significantly impairing essential behavioral patterns.
The regulatory definition is removed. The word “harm” remains in the Act, but the agencies say habitat modification or degradation does not qualify as “take.”
The Endangered Species Act itself is still in force.
Federal agencies must still ensure that actions they authorize, fund, or carry out do not jeopardize listed species or destroy or adversely modify designated critical habitat.
Each outer square shows what once existed. The filled square shows what remains.3
The new gap may matter most on private land where no federal permit, funding, or other federal action is involved. Critical-habitat protections still apply to federal actions, but generally do not restrict purely private activity without that federal connection.
About the figures. The filled square is scaled by area, so its size matches the reported remaining share. The measures differ by species: total historic geographic range for the red wolf, Florida panther, and grizzly bear; a specific habitat or ecosystem type for the ocelot (Lower Rio Grande Valley thornscrub), salt marsh harvest mouse (San Francisco Bay tidal marsh), Attwater's prairie-chicken (Gulf coastal prairie), red-cockaded woodpecker (longleaf pine), northern spotted owl (old-growth forest), and Fender's blue butterfly (Willamette Valley native prairie); and population abundance for the elkhorn coral. Some of these species, such as the grizzly bear, have since expanded from their historic lows under ESA protection. Full sources appear below.
None of these recoveries had a single cause. Habitat protection worked alongside captive breeding, reintroduction, pesticide bans, hunting restrictions, disease control, and monitoring.
The ESA helped give these species the time and space to recover. The new rule removes one way it has limited habitat destruction that kills or injures protected wildlife.
Each chart begins at a documented low, often before the Endangered Species Act was passed in 1973, and ends with the latest available count. The increases that followed reflect decades of habitat protection, captive breeding, reintroduction, pesticide restrictions, hunting controls, and other recovery work carried out under and alongside the ESA.4
The administration argues that the old definition turned indirect habitat effects into federal liability, left landowners unsure when a permit was required, and added unnecessary costs to farming, ranching, construction, fishing, and energy projects.
The administration says direct harm to animals remains illegal, while habitat is still covered when a federal agency funds, permits, or carries out a project.
A nesting tree can be felled, a spawning stream drained, or a migration corridor cut off without anyone touching the animal itself. Under the old rule, habitat damage counted as harm only when it actually killed or injured wildlife. It was never a blanket ban on land use.
Critics respond that those protections do not cover the same ground. Critical-habitat review generally applies only when a federal agency funds, permits, or carries out an action, leaving a larger gap for activity on private land without a federal connection.
The ESA's record is also hard to dismiss: fewer than one percent of listed species have gone extinct after receiving its protection.4
A coalition of conservation groups filed a federal lawsuit on July 14, challenging the new rule as contrary to the ESA and decades of legal precedent.
The public comment period has closed. The rule is scheduled to take effect on September 14, unless a court blocks it. Congress can act, and states can keep or strengthen protections under their own laws.
Ask them to restore the longstanding definition of “harm,” including significant habitat modification that actually kills or injures protected wildlife.
I’m asking you to support restoring the longstanding Endangered Species Act definition of “harm,” including significant habitat modification that actually kills or injures protected wildlife. Habitat destruction should not fall outside the law simply because the animal is not directly touched.
Legal challenge filed July 14, 2026. Case No. 2:26-cv-02474, U.S. District Court, Western District of Washington.