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DNA Barcoding: Cracking Down on Bushmeat
Geneticists are using the building blocks of life to combat a horrific illegal trade.

Last summer students from High Tech High in San Diego, led by Dr. Jay Vavra (center), traveled to Tanzania, where they discussed how to fight the illegal bushmeat trade with hunters, wildlife officials, and students such as those shown here at the Nou Forest School.
Sam Bozzette

Gorilla. Duiker. Mandrill. The six fingernail-sized pieces of dried, smoked meat ready to be analyzed on the warped table in an impromptu lab in the Cameroonian jungle could belong to any, or none, of these animals. That’s what Sarah Burgess-Herbert, a biologist at the Zoological Society of San Diego, California is here to find out. Using minimal equipment, Burgess-Herbert is testing whether she can extract DNA sequences, or bits of genetic information called barcodes, from these samples confiscated by Cameroon’s Ministry of Forestry and Wildlife. Then she’ll try to identify their origin. It’s a process that’s easily done in a traditional laboratory, but it’s a challenging feat in this remote locale, where sterile space, supplies, and equipment can be hard to come by.

If the experiment is successful, the portable laboratory could help to crack down on the illegal bushmeat trade. Not all wild animal meats are illegal to sell, but with more logging, roads, and access to previously untouched areas, hunters can reach rare, exotic wildlife, which end up in the market. Instead of sending meat samples elsewhere to be tested, a mobile test kit could help local authorities better track which species are being sold illegally as bushmeat, and provide evidence to prosecute providers of these illicit victuals. Burgess-Herbert is just one researcher in an international effort to curtail the bushmeat crisis using forensic genetics.

“As somebody who has worked on DNA studies for a long time, I said, ‘These should be easy to identify if you have a data set of samples,’ so we started a collection of referenced specimens,” says geneticist Oliver Ryder, also of the Zoological Society of San Diego, who is leading the effort there. “DNA barcoding is a tool right now that we think can make a difference, and that’s what we want to do.”

Illegal bushmeat hunting is one of the most egregious and significant threats to animals around the world, from primates in Africa to elephants and tigers in Asia to jaguars in South America. Combined with other threats, like habitat destruction and global warming, the bushmeat trade could push endangered species closer to extinction.

“I see no difference between sequencing blood from a crime scene and identifying confiscated samples of species facing the peril of extinction,” says Sergios-Orestis Kolokotronis, the coordinator of the DNA barcoding initiative for conservation at the Sackler Institute for Comparative Genomics.

As anyone who’s ever seen CSI or Law and Order knows, scientists can match blood or hair samples to an individual by looking at specific regions of DNA. This concept is also employed to identify certain animals: One gene in particular, cytochrome oxidase 1, is used to identify differences between a vast number of species. Today researchers use this technique to identify genetic differences in populations of humpback whales, to determine if captive thick-billed and scarlet macaws can be reintroduced into the wild, and even to reveal which type of parasite is infecting elephants with tuberculosis. But its application in tracking illegal bushmeat has taken off only in the past few years, and the technology is still being fine-tuned.

As barcoding technology improves, it will become cheaper and easier to use, says Burgess-Herbert. In five to ten years there may even be small handheld devices that can scan animal tissue—whether it’s raw, smoked, or in some other form. “You could have something the size of a PDA that you put a little piece of tissue in, and whether you’re an ecologist or a law-enforcement official, it tells you what the species is. That’s the vision that people have for the power of DNA barcoding and being able to identify species,” says Burgess-Herbert.

The technology has a ways to go before that goal is realized, but already it’s being put to use—in some instances, by high school students.

Jay Vavra incorporated the DNA barcoding technology into the biology class he teaches at High Tech High in San Diego. His students looked at whether the fish in local markets were labeled correctly, and identified roadkill based on genetic analysis. After they learned about the bushmeat crisis, the students asked to take a trip to Africa to learn about the trade firsthand. Vavra partnered with organizations, including Ryder’s group, and planned a trip.

This past summer Vavra took a handful of students to Tanzania, where they spoke with local Maasai, Iraqw, and Hadza tribesmen to learn about how they coexist with wildlife and to make an educational documentary.
Megan Morikawa

This past summer Vavra took a handful of students to Tanzania, where they spoke with local Maasai tribesmen to learn about sustainable bushmeat hunting and to make an educational documentary. “It’s really special, the whole experience, just for them to take this classroom lesson and then realize the true need for their design and developments and ingenuity and how those could be implemented to preserve biodiversity in Africa,” says Vavra. (To see the students at work, click here.)

In fact, while they were there, the kids identified how they could help local officials conduct DNA barcoding. Next summer they hope to return to Tanzania and help train authorities about how to use the techniques they employed in class to identify bushmeat samples. In the meantime, they’re working to raise funds for the trip. Although each country is different when it comes to penalizing those who possess illegal bushmeat, the DNA barcoding technology could make identification easier if it’s shared with the people prosecuting the offenders.

Students interviewing Lazarus Saruni, a park warden in Tanzania, for their documentary.
Steve Pye

The students also made a documentary about the illegal bushmeat trade, called “Students of Consequence,” which they started showing when they returned to San Diego. In December they won the National Council for Science and the Environment award for best overall video.

Burgess-Herbert has also experienced success with her bushmeat endeavors. During her trip to Cameroon, she demonstrated that it is possible, using a portable laboratory with just the basics, to identify unrecognizable samples of an animal using DNA barcoding. “Out of the six that we did, we got a very good sequence for everything,” she says. Most of the samples were duiker, a small antelope, but one was primate.

Although the technology she used is in its infancy, and may not be the best tool to identify samples until a few years from now, the work the researchers—whether they’re established scientists or pursuing high school diplomas—are doing is bringing attention to the global illegal bushmeat trade.

“We’re beyond who is to blame, and now we’re losing species,” says Kolokotronis. “Science is only an advisory force. It’s all about raising awareness and making people understand.”


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