DNA Forensics in Pangolin Wildlife Crime: How Genetic Science Fights Trafficking

A pile of dried pangolin scales sits in an evidence room at a South African police station. They could belong to any of eight pangolin species spread across two continents. They could have been poached in Limpopo or smuggled from Cameroon. To the untrained eye, the scales look identical. But to a forensic geneticist, each one carries a molecular signature that can identify the species, pinpoint the geographic origin, and link the evidence to a specific criminal network.

DNA forensics has become one of the most powerful tools in the fight against pangolin trafficking. As the world's most trafficked wild mammals face relentless pressure from illegal trade, genetic science is giving investigators, prosecutors, and conservationists the evidence they need to fight back.

The Identification Problem

Pangolin scales from different species are morphologically similar, making visual identification unreliable. This matters because all eight species were uplisted to CITES Appendix I in 2016, banning all international commercial trade. Proving which species is involved determines which laws apply and the severity of penalties. Processed or mixed seizures, where scales from multiple species and source countries are combined, make the problem worse.

DNA barcoding solves this. Forensic scientists extract mitochondrial DNA from scale samples and amplify specific gene regions, primarily COI (the standard DNA barcode gene) and Cytochrome b. These sequences are compared against taxonomically verified reference databases to reliably distinguish all eight extant species.

The foundational study for African pangolin forensic identification was published in 2017 by Dr Monica Mwale and colleagues at SANBI, South Africa's National Biodiversity Institute. Their paper in the journal Genome demonstrated that DNA barcoding could accurately identify illegally traded African pangolin scales, providing a validated forensic tool for enforcement authorities.

South Africa's Forensic Laboratories

South Africa is one of the few African countries with dedicated wildlife forensic DNA capacity. Two principal laboratories handle the bulk of casework.

The SANBI Genetic Services Unit in Pretoria maintains DNA barcoding reference libraries for South African fauna, including pangolins. Led by researchers including Dr Monica Mwale, the unit processes forensic cases for the South African Police Service, the Green Scorpions, and other enforcement authorities. It receives funding through the GEF7 project to enhance forensic support for wildlife trafficking investigations.

The Veterinary Genetics Laboratory at the University of Pretoria complements SANBI's work with validated forensic markers, including microsatellites and single nucleotide polymorphisms specifically developed for Temminck's ground pangolin. These markers enable individual identification, linking a specific seized scale to a specific animal, which strengthens evidence chains in prosecution.

Between August 2017 and July 2024, these two laboratories collectively analysed 3,763 wildlife forensic cases across all species in South Africa. The caseload reflects both the scale of wildlife crime and the growing reliance on genetic evidence in prosecution.

Mapping the Supply Chain

Identifying the species is only the first step. To dismantle trafficking networks, investigators need to know where the pangolins were poached. This is where phylogeography, the study of geographic patterns in DNA variation, becomes critical.

By comparing DNA profiles from seized scales against georeferenced reference samples from known wild populations, researchers can trace trafficked pangolins back to their source region. A landmark 2023 study published in Science by Heighton and Gaubert mapped the white-bellied pangolin genome using 111 samples from known Central African localities, identifying Nigeria as a major regional trafficking hub with onward routes to China, Thailand, Vietnam, Laos, and Singapore.

Their follow-up study in 2026, published in PLOS Biology, went further. The team sequenced over 700 samples from three pangolin species, including museum specimens and bushmeat market samples, and developed a single gene-capture kit that works across all eight species. The resulting genomic reference map can trace trafficked pangolins to their geographic origin with a median accuracy of approximately 72 kilometres. The study identified poaching hotspots in southwest Cameroon and Myanmar, and revealed that domestic bushmeat trade overlaps with the same source regions feeding international trafficking networks.

Separately, researchers used Oxford Nanopore's MinION portable sequencing platform to genotype 2,346 scales from 37.5 tonnes seized in Singapore in 2019. The analysis identified all six known phylogeographic lineages of African pangolins among the seized material, indicating that poaching draws from the species' entire continental range rather than isolated pockets.

In the Courtroom

Between 2016 and 2024, 302 Temminck's pangolins were recovered from illegal trade in South Africa. Of these, 81.4 percent were still alive at the point of recovery. A total of 679 suspects were arrested across 276 separate police operations, with pangolins retrieved in eight of the country's nine provinces.

Under NEMBA, the maximum penalty for illegal activities involving threatened or protected species is 10 years imprisonment and a R10 million fine. In a landmark 2019 case, the African Pangolin Working Group, the Cullinan Stock Theft and Endangered Species Unit, K9 units, and the Green Scorpions conducted a sting operation in which a pangolin was offered for sale to an undercover agent. The female pangolin later died of malnourishment, dehydration, and physical injuries. The principal offender received the full 10-year sentence without option of fine, described by the National Prosecuting Authority as the highest sentence ever imposed for pangolin poaching in South Africa. Prof Ray Jansen provided expert evidence in aggravation of sentencing.

Internationally, genetic evidence has supported significant convictions. In Nigeria, three Vietnamese nationals and one Guinean were sentenced to six years each in 2024 for trafficking 7.1 tonnes of pangolin scales and 850 kilograms of ivory. In the United States, the National Fish and Wildlife Forensics Laboratory confirmed pangolin scale identification using laboratory analysis in a 2021 Portland prosecution.

Emerging Technologies

Several advances are expanding what forensic science can extract from pangolin evidence.

A species-specific digital PCR assay developed in 2025 targets a 116-base-pair fragment of the 16S ribosomal DNA gene. This approach works on highly degraded samples where conventional PCR fails, which matters because seized scales are often heat-treated, dried, or chemically processed by traffickers before confiscation.

Researchers have also discovered that pangolin scales transfer detectable amounts of DNA onto the plastic bags used for transport. Using a nucleic acid staining dye, scientists visualised latent DNA deposits and successfully amplified product from all 30 bag samples tested, the first reported use of this technique for a non-human mammal. This means that even the packaging materials in a seizure can yield forensic evidence.

On the human identification side, researchers at the University of Portsmouth and the Zoological Society of London developed a gelatine-lifter method to recover human fingerprints from pangolin scales, achieving a 74 to 90 percent success rate. Field-testing kits are being deployed to wildlife rangers in Cameroon and Kenya, connecting the physical handler to the trafficked product.

The Gaps That Remain

For all its promise, DNA forensics in pangolin crime faces real constraints. Geographic reference databases remain incomplete. The Heighton and Gaubert reference map, the largest to date, covers only three of eight species. Regions within pangolin range states where no reference samples exist represent blind spots in geographic tracing.

Laboratory capacity in Africa is concentrated in South Africa. Most other range states lack accredited wildlife forensic labs, and the equipment, reagents, cold-chain storage, and reliable electricity required for genetic analysis remain scarce in many countries where pangolins are poached.

Admissibility standards create another bottleneck. Wildlife DNA evidence must meet the same forensic rigour as human DNA evidence in court, including validated methods, accredited laboratories, and documented chain of custody. A 2026 conviction of a lion trafficker using DNA evidence was reported as a world first for large mammal trafficking, suggesting that DNA-as-decisive-evidence precedents in wildlife crime are still being established.

And there is the matter of scale. Over 370 tonnes of pangolin scales were seized globally between 2015 and 2024. Each seizure represents a forensic opportunity, but the volume of confiscated material vastly exceeds the capacity of existing laboratories to process it.

Building the Foundation

DNA forensics will not stop pangolin trafficking alone. No single tool can. But genetic science does something no other enforcement method offers: it converts anonymous biological material into actionable intelligence. A dried scale becomes a species, a source region, a trafficking route, and ultimately a piece of evidence that can put a poacher in prison for a decade.

South Africa, with its two forensic laboratories, its world-leading pangolin researchers at SANBI, the University of Pretoria, and the African Pangolin Working Group, and its legal framework under NEMBA, is better positioned than most countries to use this tool effectively. The challenge now is expanding that capacity across the continent, so that every seizure, in every range state, can be turned into evidence that sticks.