The use of DNA testing, originally developed for investigating human crimes, has now expanded to combat the illegal harvesting of endangered forest species.
In a story I wrote in mid-2021 I covered the African cherry, or Prunus africana, and how DNA testing is being utilised to track the harvest of its highly lucrative bark. In the coming weeks I will be providing a further update about this project.
About the African cherry: highly lucrative but growing concern over harvest
The recent International Day of Forests emphasised the importance of forest for health, and the African cherry is one of the most lucrative tree species extracted for medicinal purposes. Its bark is exported as dried, chipped or powdered with the international trade in the bark is valued at $220 million (USD) and is increasingly being used to treat malaria, kidney disease and prostate discovers.
According to the FAO, the commercialisation of the tree has been a major alleviator of poverty in Central and South Africa.
Concerns about its unregulated harvesting led to the species’ inclusion in Appendix II of the Convention on International Trade in Endangered Species (CITES) in 1995, in 2006 concerns over declining populations of the tree led to the European Union enforcing an import ban in 2007.
The tree can endure some bark removal; however, improper practices and excessive stripping result in its death. As a result, the International Union for Conservation of Nature (IUCN) designated the African cherry as “vulnerable” on their Red List, and it falls under CITES Appendix II, requiring trade regulation to prevent utilization that endangers the species’ survival.
CITIES and the ITTO work together to protect tropical tree species
In 2006, CITES partnered with the International Tropical Timber Organization (ITTO) to assist countries in implementing CITES regulations for tropical tree species. This collaboration remains robust in 2023.
“This exemplary collaboration demonstrates how international organizations and the worldwide community can unite to safeguard treasured tree species, benefiting both humans and the vast array of wildlife that relies on them.”Sheam Satkuru, ITTO Executive Director
In Cameroon, a 2009 project began with an assessment of African cherry trees and documentation of harvest levels.
The project promoted controlled, sustainable harvesting in Cameroon’s primary production areas and other African nations, including the Democratic Republic of the Congo. As a result, Cameroon produced the “Non-Detriment Finding” required by CITES, leading to the endorsement of a conservative export quota and the resumption of trade. The initiative also addressed the issue of blending bark from unregulated regions with products from authorized, controlled areas.
The program was overseen by the ITTO-CITES Programme Regional Coordinator in Africa, Professor Jean Lagarde Betti. He utilized an extensive network of stakeholders, such as government officials, private sector representatives, and local communities, who had been cooperating on CITES-listed tree species in the region since 2008.
The project unfolded in two phases:
• Phase 1 (2008-2012) prioritized constructing inventories, devising simple management plans, setting annual quotas, and developing non-detriment findings;
• Phase 2 (2012-2015) focused on implementing management plans and adhering to non-detriment findings recommendations.
DNA Barcoding: A Tool for Identifying Illegally Exported African Cherry
For the second phase of work in Cameroon, ITTO-CITES required assistance in establishing a DNA verification system for Prunus africana.
In 2014, Double Helix Tracking Technologies was called on to coordinate exploratory work on the genetic variation of the African cherry, which was scattered across the mountain ranges of tropical Africa and Madagascar.
In partnership with the Advanced DNA Identification and Forensics Facility at the University of Adelaide, a major body of work was undertaken to understand if it was possible to differentiate between bark from controlled and uncontrolled harvest areas, and so identify and exclude uncontrolled, unsustainable supply from the market.
University of Adelaide researcher Professor Andrew Lowe said at the time “we used the latest genomics methods to develop and apply a simple DNA test for African cherry”.
“The initial scientific results showed significant genetic variation between populations – even those less than 10 km apart.
“These results are tremendously promising and warrant further investigation, particularly to establish if differences can be identified at the annual plot level.”
“It’s also particularly important that this DNA work supports the implementation of simple management plans, and that local staff are trained in sampling and analysis procedures”, explains Professor Lowe.
Sampling can be risky business
One man on the ground who worked on this project and collected a lot of useful information, is Germain Yene, the Regional Coordinator for DoubleHelix.
Did Germain encounter any resistance to his work in helping to manage the African cherry bark according to CITES rules?
“In the field, we took samples at different points in the supply chain from batches of bark in the field to products prepared for sale or export.”
“Interestingly the sampling teams collecting bark did not encounter any resistance from the local people, only curiosity.”
He also pointed out that the areas open to the exploitation of Prunus africana tend to be natural forests, where the species has been growing naturally.
“However, there are local people in some areas who have planted Prunus and can seek to sell it by mixing it with the bark from the sites authorized for harvesting.
“It was made clear to all concerned that this work was being supervised by the administration in charge of forests and the environment to support CITES requirements, and which therefore had the potential to support good business operators”.
But he admitted that it can be risky work. Germain recounted that in the Lake Kivu region of the Democratic Republic of Congo, the local sampling team once came face to face with armed rebels “who confiscated their samples and working equipment”, but no one was harmed in the encounter.
Where to from here?
- The next phase of the project, a partnership funded by ITTO between the University of Adelaide, the Ministry of Forestry in Cameroon, the Faculty of Sciences of University of Douala and DoubleHelix), and started in Cameroon in May 2021 and involving four key objectives:
- Implementing an effective DNA traceability system to control trade in Prunus africana, as well as Pericopsis elata – commonly known as African teak.
- Collecting samples of P. africana and P. elata from different populations in Cameroon.
- Developing new genetic markers for P. africana, suitable to differentiate between populations in neighbouring areas.
- Analysing all samples with genetic markers to determine the most appropriate level of discrimination at different population levels for each species, such as “Prunus Allocation Units” or annual harvesting plots.
Working under the supervision of the Cameroon Ministry of Forestry and the Faculty of Sciences of University of Douala, Germain collecting samples from across Cameroon.
“Among other selection criteria, it will be necessary to have a good knowledge of the species – its ecology and distribution. When it comes to implementation of a DNA verification system, it is also a question of identifying the different handling points for samples and products along the supply chain, from the forest to the port of embarkation,” Germain explained.
“We will take a random assortment of bark and product samples, which will be compared to the genetic reference database to verify that they are from the claimed harvest area or not.“
Germain says we should think of it as a quality control system, but instead of checking for the physical quality of the bark, he is checking for the quality of its environmental claims.
DNA traceability essential to stop depletion of endangered species
Overseeing the collaborative project in Cameroon, Prof Betti sees this advanced DNA traceability project as essential to stop the depletion of endangered tree species and to control the trade in Prunus africana, as well as Pericopsis elata.
“While we accept that the African cherry has important international value as a medicine, we must find a way to stop the illegal harvesting of its bark. Of course, the tree is resilient to some bark removal, but poor and excessive bark stripping leads to death of the tree. This must stop,” Prof Betti insists.
- This article was sourced from extracts from a story Ken wrote for DoubleHelix Tracking Technologies. In the coming weeks, Ken will provide an update on the project.