In 2003, João Miguel Folgosa walked into the Recife/Guararapes–Gilberto Freyre International Airport in Brazil with a ticket to Lisbon in his hand and five nylon stockings wrapped around his abdomen. They held 58 eggs, carefully packed in paper napkins underneath his shirt. He headed toward the departure lounge and waited to board his flight, but federal police officers recognized him as the leader of an international gang of wildlife trafficking and swooped in. After his arrest, Folgosa claimed he was carrying quail eggs. Authorities suspected they were actually parrot eggs, bound for the exotic pet market. But there was no way to tell who was right, because the confiscated eggs never hatched. Folgosa was released a few days later.

When Cristina Miyaki, a biologist at the University of São Paulo in Brazil, heard about the Folgosa case, she knew there had to be a better way to catch and convict wildlife smugglers. Now, she and her colleagues have published two papers that could help solve smuggling cases and design better conservation strategies in Brazil and beyond.

Wildlife smuggling is a major headache all over Latin America, but in Brazil it has evolved into a growing and profitable industry that is worth up to $2 billion a year, according to the Brazilian Institute of Environment and Renewable Natural Resources. “[Brazil’s] borders are hard to control and its extraordinary biodiversity is often seen as easy money by trafficking networks,” says Juan Carlos Cantú, a biologist in Mexico City who manages the Mexico office of Defenders of Wildlife, a conservation group in Washington, D.C. Birds are especially vulnerable, and parrots top the list of threatened species because of the high demand for them in the pet market.

As the Folgosa case shows, identifying smuggled wildlife isn’t always straightforward. Many smugglers transport birds as eggs or chicks, when it can be difficult to determine their species just by looking at them. Miyaki used an alternative method: genetic testing. Using the 58 eggs confiscated in the Folgosa case back in 2003, she and her team searched for short DNA sequences that coded for a piece of the ribosome, the cell’s protein-producing factory. These sequences are specific to particular bird species, much like molecular barcodes. They then spent years sequencing other species-specific markers, like mitochondrial genes, which could support their work and finally compared them with a very large database of wild bird DNA to find any matches.

Their results, which appear this month in the Journal of Heredity, confirmed what the wildlife authorities had feared: Fifty-seven embryos belonged to wild parrot species, and one was an owl. Using such DNA tests to identify smuggled animals as soon as they are confiscated “can help the authorities establish stronger criminal cases against traffickers,” Miyaki says. But even though it was too late to prosecute Folgosa based on Miyaki’s test, she did learn something from the cold case that could help law enforcement today. Most of the bird embryos belonged to yellow-faced parrots, suggesting that this species could be a common target for poachers—information the police could use to develop more focused protection plans for the birds.

Still, the story of smuggled birds does not always end with confiscated eggs. When live animals are seized, police and scientists hope to be able to release them back into the wild. But because most are confiscated far from where they were initially trapped, it’s often unclear where they come from. “The biggest problem here is releasing animals with no known origin,” says Juliana Machado Ferreira, a conservation geneticist who directs Freeland Brasil, an anti–wildlife-trafficking organization in São Paulo. Diseases, invasive species, disruption of reproductive cycles, and less fit hybrid offspring are just some of the risks that parrots and other species face when they are released in unfamiliar places and begin to reproduce with individuals from different populations. Without proper rehabilitation, “you are basically freeing them to their death,” says Cantú, who was not involved in the new studies.

So what if scientists could somehow determine the geographic origin of seized birds? Miyaki says it’s possible, thanks to population genetics. She and her colleagues published another paper in the same issue of Journal of Heredity about blue macaws, the charismatic and threatened parrots made famous by the animated film Rio. “The little ecological information we have about blue macaws suggest there are three isolated populations [in Brazil],” Miyaki explains: one from Amazonia in the north, another from the grasslands of the northeast, and the last one from the Pantanal, a vast wetland that stretches across the central states of Mato Grosso and Mato Grosso do Sul.

Making use of the DNA in blood samples collected from wild macaws, the team found that over time the Pantanal group has divided into two genetically different populations, whereas the north and northeast groups have fused into one. The researchers then worked with the wildlife authorities to try to determine the probable source population of chicks that had been recently confiscated. The suspected smuggler claimed he had caught them in the Pantanal, “but our genetic data strongly suggested that these birds were not from there, but from the north and northeast areas,” Miyaki says. “If this is correct, the trafficker was just passing through the Pantanal to get to the border of another country, possibly Bolivia.” Such data could not only help the birds return home, but also might shed light on current trafficking routes in Brazil.

According to Machado Ferreira, who was not involved in the research, Miyaki’s work is an excellent example of cooperation between scientists and the police. But scientific research “is meaningless if we lack law enforcement and awareness,” she says. Wildlife crimes in Brazil are misdemeanors, carrying no or little jail time.

The situation is no better in other countries hit by wildlife smuggling, like Mexico. “Scientific advances may assist the authorities to do a better job,” Cantú says, but that doesn’t mean they can stop illegal trafficking. To do that, he says, you have to stem the demand. The best way to help? Cantú says it’s simple: “Don’t buy parrots.”