Radiocarbon dating of seized ivory confirms rapid decline in African elephant populations and provides insight into illegal trade.
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.
IsoForensics, Inc., Salt Lake City, UT 84108; thure.cerling@utah.edu.|Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112.|Department of Biology, University of Utah, Salt Lake City, UT 84112.
Thure E
TE
Cerling
IsoForensics, Inc., Salt Lake City, UT 84108.
Janet E
JE
Barnette
IsoForensics, Inc., Salt Lake City, UT 84108.
Lesley A
LA
Chesson
Save the Elephants, Nairobi 00200, Kenya.|Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom.
Iain
I
Douglas-Hamilton
Wildlife Program, Vulcan, Inc., Seattle, WA 98104.
Kathleen S
KS
Gobush
Lamont-Doherty Earth Observatory, Division of Biology and Paleo Environment, Columbia University, Palisades, NY 10964.
Kevin T
0000-0001-6882-0900
KT
Uno
Center for Conservation Biology, Department of Biology, University of Washington, Seattle, WA 98195.
Samuel K
SK
Wasser
Department of Earth System Science, University of California, Irvine, CA 92697.
Xiaomei
X
Xu
D000818:Animals; D002163:Cameroon; D002250:Carbon Radioisotopes / Q000378:metabolism*; D003132:Commerce; D003223:Congo; D003247:Conservation of Natural Resources; D003415:Crime; D004606:Elephants; D005681:Gabon; D011157:Population Dynamics / Q000639:trends; D055110:Radiometric Dating / Q000379:methods*
D002250:Carbon Radioisotopes
Africa; forensics; genetics; isotopes; wildlife