We, the U.S. Fish and Wildlife Service (Service), announce a 90-day finding on a petition to list Sierra Nevada red fox (Vulpes vulpes necator) as endangered or threatened under the Endangered Species Act of 1973, as amended (Act), and to designate critical habitat. Based on our review, we find that the petition presents substantial scientific or commercial information indicating that listing this subspecies may be warranted. Therefore, with the publication of this notice, we are initiating a review of the status of the subspecies to determine if listing Sierra Nevada red fox is warranted. To ensure that this status review is comprehensive, we are requesting scientific and commercial data and other information regarding this subspecies. Based on the status review, we will issue a 12-month finding on the petition, which will address whether the petitioned action is warranted, as provided in section 4(b)(3)(B) of the Act.