Genetics and Wildlife Forensics once more together against illegal trade of species.
Harnessing the potential of Genetic Tools to tackle wildlife illegal traffic it is not such a new history, and has already proved useful in many conservation projects across de globe. It is specially highly regarded in forensic sciences in countries like Australia, New Zealand, Canada and different parts of Europe and its incorporation it’s being boosted in developing countries which have a great biodiversity to protect.
New ramifications of this application continue to emerge as the technologies advance, the example I want to show you today it is about a common practice when it comes to wild or exotic pets, which is the laundering of wild caught animals as “captive bred”. This is the specific case of the Broad-headed snake -BHS (Hoplocephalus bungaroides), endemic to Australia, and whose populations have been threatened by illegal extraction since the early 20th Century.
In this new paper Dr. Carolyn J. Hogg (from the Australasian Wildlife Genomics Group, of The University of Sydney) and collaborators assess the feasibility of using genetic samples to track the relationships between the BHS individuals kept in captivity either by private owners or zoos and wild individuals, so that it would be possible to distinguish actual captive bred animals and to develop the test to aid other species in similar conditions.
For the trial they worked with samples collected from private keepers as part of a regulation started in 2010, in which they were required to microchipped the snakes and provide tissue samples. Also used genetic material from zoos (with well known pedigrees) and “wild samples” obtained from different sources (e.g. road kills, museum collections). They applied both microsatellite and mitochondrial sequences analyses in order to calculate the Genetic differentiation (FST) and relatedness.
Their findings showed that the samples were grouped in two clusters. One cluster consisted entirely of “zoo” samples, and the second cluster comprised all “wild” and “private” samples. Since the “zoo” group “lineage” was founded by only 5 individuals, the researchers conducted further analyses including and excluding the “zoo” group, to ensure that their high level of relatedness was not causing clustering of the “private” and “wild” sample groups. Nonetheless, the removal of the zoo samples did not change the clustering pattern.
They highlight the fact that the differentiation from the matrilineal line of the zoo individuals, was noticeable after only three generations (one generation being of 8 years) of captivity, in contrast with the results of the privately owned BHS which does not seems to be a closed population, as not significant differences (considering that the species has been required to be held under license since 1997) were shown between them and the “wild” sample group. Rather the diferentiation suggests that there may have been recent “additions” sourcing from the wild.
Although the results are very encouraging, there remains the difficulty of determining whether the clustering is a result of actual illegal activities or is the result of low population diversity. Despite this downside and some other challenges for the test, it is a great start to enhance and adopt the approach of bio-backing of DNA samples to allow the construction of pedigrees and the development of forensic tools that will help regulatory authorities to better centralized and manage the licensing conditions. The document also points out at the importance of integrative and inclusive work among zoo industry, policy makers and researchers.
READ THE ORIGINAL PAPER HERE!!!