On February 23, the U.S. Fish and Wildlife Service (Service) issued a proposed rule to list two distinct population segments (DPSs) of the California spotted owl (Strix occidentalis) as endangered and threatened species under the Endangered Species Act (ESA). The two DPSs are the Coastal-Southern California DPS, which the Service proposes to list as endangered, and the Sierra Nevada DPS, which the Service proposes to list as threatened with a rule issued under section 4(d) of the ESA (4(d) rule). The proposed rule also serves as the Service’s 12-month finding on a petition to list the California spotted owl.

The California spotted owl is one of three subspecies of spotted owls. It is a medium-sized, brown owl with mottled plumage, a round face, pale facial disks, dark brown eyes, and a yellowish-green bill. California spotted owls are distributed across habitat in California and Nevada. As their names imply, the Sierra Nevada DPS is found in forests east of California’s Sierra Nevada mountain range, while the Coastal-Southern California DPS is scattered throughout the Southern California coast, in pockets of suitable habitat surrounded by inhospitable terrain. According to the Federal Register notice, these two DPSs comprise the entirety of the California spotted owl's range.

In the proposed rule, the Service explains its rationale for listing these two DPSs of California spotted owl. The Service writes that the Sierra Nevada DPS is negatively impacted by high-severity fire, tree mortality, drought, and predation by barred owls, and the Service expects these stressors to become more severe over time. Therefore, although the Sierra Nevada DPS still has some resiliency throughout its range, the Service concludes that a “threatened” listing is appropriate for this DPS. With respect to the Coastal-Southern California DPS, the proposed rule describes this population as having low resiliency, redundancy, and representation. The Service determined that threats including high risk of wildfires, habitat fragmentation, tree mortality, and drought put this population of the species in danger of extinction, making an “endangered” listing appropriate.

The Federal Register notice states that the proposed rule will be open for public comments until April 24, 2023. The notice and supporting documents are available at regulations.gov, under Docket Number FWS-R8-ES-2022-0166.