43 U.S.C. § 687c–1

section 687c of this titleThe Secretary of the Interior is authorized to perform any and all acts, and to make such rules and regulations as may be necessary and proper, for the purpose of carrying the provisions of into effect, including provisions for the forfeiture of any lease for failure to stock the same with fur-bearing animals within a period of one year from the date of the lease, or in the event of the devotion of the lease area primarily to any purpose other than the rearing of such fur-bearing animals.