posted on 2021-02-03, 04:02authored byVincent NaudeVincent Naude, Vivienne L. Williams, Marli de Bruyn, Peter G.R. Coals, Desiré L Dalton, Antoinette Kotzé
<p>From 2008 to
2018, South Africa permitted the export of captive-bred African lion (<i>Panthera leo</i>) skeletons to Southeast
Asia. Exports rose from approximately 50 individuals in 2008 to a maximum of 1,771
skeletons in 2016, leading to concerns over possible laundering of non-lion,
multiple-source and wild material. Monitoring tools for the legal trade in lion
bones are critical to CITES compliance, ensuring that i) other species are not laundered
as lion, ii) all bones in a consignment comprise of a known number of unique
individuals to avoid ‘pooling’ or ‘tag-swopping’, and iii) each individual can
be traced to their captive origin. In addition to exploring conventional skull
morphology- and weight-based monitoring techniques, a CITES-compliant genetic
monitoring protocol to confirm the species, individual identity, and thereby the
origin of legally traded lion bones was developed and validated. We traced 800
and 799 lion bone samples obtained under ‘chain-of-custody’ sampling from the
2017 and 2018 lion bone quotas, respectively, while an additional 25 and 102
random ‘spot-checked’ samples were collected at the airport prior to export. A
real-time polymerase chain reaction was used for species assignment, while pairwise-comparative
sample matching of individual DNA profiles and origin tracing analyses were
conducted using 18–23 microsatellite markers. There are significant differences
in lion skeleton weights: farm weights (listed on CITES export permits) are
heavier than export weights, and skeletons in more recent trade are heavier
than in preceding years. Monitoring skeleton weight profiles can provide
significant regulatory advantages when correctly applied, but it may be prone
to misinterpretation and should be considered in the full context of the
procedural system. Molecular identification of individuals and species
successfully highlighted ten anomalies in comparative sample matching of
individual pairs with the same tag number between source farms and airport
spot-checks, excluding one overt attempt at laundering. We here provide both
the lion weight and genetic profile data to support these analyses. </p>