Radiocarbon dating of seized ivory confirms rapid decline in African elephant populations and provides insight into illegal trade

Proc Natl Acad Sci U S A. 2016 Nov 22;113(47):13330-13335. doi: 10.1073/pnas.1614938113. Epub 2016 Nov 7.

Abstract

Carbon-14 measurements on 231 elephant ivory specimens from 14 large ivory seizures (≥0.5 ton) made between 2002 and 2014 show that most ivory (ca 90%) was derived from animals that had died less than 3 y before ivory was confiscated. This indicates that the assumption of recent elephant death for mortality estimates of African elephants is correct: Very little "old" ivory is included in large ivory shipments from Africa. We found only one specimen of the 231 analyzed to have a lag time longer than 6 y. Patterns of trade differ by regions: East African ivory, based on genetic assignments of geographic origin, has a much higher fraction of "rapid" transit than ivory originating in the Tridom region of Cameroon-Gabon-Congo. Carbon-14 is an important tool in understanding patterns of movement of illegal wildlife products.

Keywords: Africa; forensics; genetics; isotopes; wildlife.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cameroon
  • Carbon Radioisotopes / metabolism*
  • Commerce
  • Congo
  • Conservation of Natural Resources
  • Crime
  • Elephants*
  • Gabon
  • Population Dynamics / trends
  • Radiometric Dating / methods*

Substances

  • Carbon Radioisotopes