Section 17.83 - Interagency cooperation(a) Any experimental population designated for a listed species (1) determined pursuant to § 17.81(c)(2) of this subpart not to be essential to the survival of that species and(2) not occurring within the National Park System or the National Wildlife Refuge System, shall be treated for purposes of section 7 (other than subsection (a)(1) thereof) as a species proposed to be listed under the Act as a threatened species.(b) For a listed species, any experimental population that, pursuant to § 17.81(c)(2) , has been determined to be essential to the survival of the species or that occurs within the National Park System or the National Wildlife Refuge System, as now or hereafter constituted, will be treated for purposes of section 7 of the Act as a threatened species.(c) For purposes of section 7 of the Act, any consultation or conference on a proposed Federal action will treat any experimental and nonexperimental populations as a single listed species for the purposes of conducting the analyses and making agency determinations pursuant to section 7(a) of the Act.49 FR 33893, Aug. 27, 1984, as amended at 88 FR 42651 , July 3, 2023