50 CFR §14.52

1. (a)Except as otherwise provided by this subpart, a Service officer must clear all wildlife imported into the United States prior to release from detention by Customs officers. A Service officer must clear all wildlife to be exported from the United States prior to the physical loading of the merchandise on a vehicle or aircraft, or the containerization or palletizing of such merchandise for export, unless a Service officer expressly authorizes otherwise. Such clearance does not constitute a certification of the legality of an importation or exportation under the laws or regulations of the United States.
2. (b)An importer/exporter or his/her agent may obtain clearance by a Service officer only at designated ports (§ 14.12), at border ports (§ 14.16), at special ports (§ 14.19), or at a port where importation or exportation is authorized by a permit issued under subpart C of this part. An importer/exporter must return forthwith any wildlife released without a Service officer's clearance or clearance by Customs for the Service under authority of § 14.54 to a port where clearance may be obtained pursuant to this subpart.
3. (c)To obtain clearance, the importer, exporter, or the importer's or exporter's agent will make available to a Service officer or a Customs officer acting under § 14.54:
   1. (1)All shipping documents (including bills of lading, waybills and packing lists or invoices);
   2. (2)All permits, licenses or other documents required by the laws or regulations of the United States;
   3. (3)All permits or other documents required by the laws or regulations of any foreign country;
   4. (4)The wildlife being imported or exported; and
   5. (5)Any documents and permits required by the country of export or re-export for the wildlife.