The federal Endangered Species Act (ESA) has long been one of the major flash points in debates over government interference with property rights. This report outlines the ESA provisions most relevant to the act’s impacts on private property and surveys the major ESA-relevant principles of Fifth Amendment takings law. The Takings Clause of the Fifth Amendment promises “just compensation” when government actions “take” property.
The report then summarizes the court decisions on whether particular government actions (or inaction) based on the ESA “take” private property under the Fifth Amendment. The cases to date address several kinds of ESA impacts on private property: (1) restrictions on land uses that might adversely affect species listed as endangered or threatened, and mitigation conditions to offset the impacts of development; (2) administrative delays; (3) reductions in water delivery or allowable water diversion to preserve lake levels or instream flows needed by listed fish (currently the most active area of ESA takings litigation); (4) restrictions on the defensive measures a property owner may take to protect his/her property from listed animals; and (5) restrictions on commercial dealings in listed species..
To date, only one of the 18 ESA-based takings cases disclosed by research, Tulare Lake Basin Water Storage District v. United States, has found a taking. However, two cases, Casitas Municipal Water District v. United States and Klamath Irrigation District v. United States, have yet to be finally resolved and may or may not result in holdings that takings occurred.