CYCAD FORENSICS: CAN STABLE ISOTOPES AND RADIOCARBON DATING CURB ILLEGAL POACHING OF CYCADS?

 

Kirsten Retief, Michèle Pfab and Adam West

University of Cape Town, South African National Biodiversity Institute (SANBI)

 

Abstract:

The conservation status of endangered cycads is threatened by the illegal extraction of wild cycads for private collections and landscaping purposes, causing rapid decreases in populations. The conservation of wild populations has been ineffective, due to the increasing demand for wild cycads. The illegal trade continues to flourish, because of the difficulty in proving the origin of poached cycads when prosecuting poachers and collectors. We investigated the feasibility of using a suite of stable isotope ratios and radiocarbon dating to identify specimens removed from the wild. Relocated and wild (control) specimens of two species within the African genus Encephalartos were sampled: E. lebomboensis and E. arenarius. Radiocarbon analysis indicated that a ±30 year chronology could be reliably obtained from the cycads. The isotope chronology for both of our relocated specimens matched their known histories. Our multiple isotope approach allowed effective use of multivariate analyses to distinguish between wild and relocated cycads. 87Sr/86Sr and 18O showed the most potential as individual isotopic tracers, however this may vary depending on the specfic relocation history of the specimen under investigation. Our findings provide a basis for future research to use stable isotope ratios and radiocarbon dating to trace cycad origin. The successful application of this method will assist authorities in identifying the provenance of dubious ex situ cycads.

 

Presentation Topic:

CYCAD FORENSICS: CAN STABLE ISOTOPES AND RADIOCARBON DATING CURB ILLEGAL POACHING OF CYCADS?

Contact Ms Retief:
Email Kirsten Retief