Polly Want a DNA Test?

A new study looks at how genetic analysis can help fight the exotic pet trade.

August 13, 2015

A blue-fronted Amazon parrot, a species frequently captured in the wild for the pet trade
Photo: Matt Watts/Flickr

Brazil, 2003. A man tries to board a flight bound for Portugal with 58 bird eggs taped to his belly. He gets caught. “They’re only quail eggs!” he argues. Hmm…

A lot of bird eggs look alike, but to the authorities, these appeared to be more parrot than pheasant. And…they likely assumed the guy with nearly five dozen eggs hidden under his shirt didn’t have a high regard for the truth. (Exhibit A: Dennis Nedry.)

Brazil is home to 83 species of parrots, 21 of which are considered endangered at some level. So there was a very good reason the authorities wanted to know the identity of those embryos. None of the eggs hatched, so ID'ing the chicks by appearance was out.

And there was good reason for the smuggler to lie. Killing, hunting, hounding, capturing, or otherwise using wildlife without the proper licenses or authorizations is illegal in Brazil, with penalties of up to six months or a year in prison—and potentially worse if the victim is an endangered species. Gaps, however, exist between what the law states and what the courts typically enforce.

“Cases related to the illegal wildlife trade are not considered as important as other offenses, such as the illegal gun or drug trade,” says Cristina Yumi Miyaki, a biologist at the University of São Paulo. “It’s a problem of priority.”

Without really knowing what was under those 58 eggshells, the court fined the smuggler the minimum amount for each ovum offense, and he was released after a few days. But that’s not where the story ends.

For the last several years, Miyaki and her colleagues have been analyzing genetic material taken from those 58 mystery eggs. At first, they could only pin down short gene sequences, not enough to make a positive ID. But with time, the team was able to sequence a second, longer mitochondrial gene that allowed them to match the samples against a public database of genetic material. Another lucky break was the development of a second database that helped them narrow the likely identities of the eggs.

The results, published this month in the Journal of Heredity, show that in addition to being an egg smuggler, the perp was also a liar. Shocking, I know.

Of the samples, three of the eggs were blue-and-yellow macaws, four were various kinds of Amazon parrot, and one belonged to some sort of owl, likely a tropical screech owl, Miyaki says. The other 50 eggs on their way to Portugal’s pet shops belonged to the yellow-faced parrot, a species listed as near threatened due to habitat destruction and, you guessed it, the exotic pet trade.

Photo: Robert01/Wikimedia CommonsThe illegal bird trade has been blamed for the decline of the Spix's macaw, which is now believed to be extinct in the wild.

According to a study conducted last year by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), birds are by far the most popular animals in the international pet trade, with parrots being the favorite. In a piece for Audubon, Lynn Miao writes that the illegal wildlife trade “is believed to have contributed to the threatened status of 66 parrot species and the extinction of the brilliant blue Spix’s macaw.”   

Though something like 40 million pet parrots squawk in cages in the United States, Americans are mostly insulated from the smuggling practices that bring wild-caught birds to our breakfast nooks. According to a report from Defenders of Wildlife, traffickers employ sticky traps, slip knots, and mist nets to acquire birds. Some trappers even lure them in with other birds by tethering parrots to snares or wire cages. To obtain eggs and nestlings, they’ll climb trees, or simply cut them down, gathering whatever survives the fall.

Children help, too. Trappers in Mexico pay kids to search for orange-fronted parakeet nests. (The birds lay their eggs in holes scratched out of termite mounds.) The traders then stop back once or twice a month to pay the children a pittance and collect what they’ve found.  

How the egg-nabber acquired his contraband is still unclear, even though authorities had been keeping an eye on him. Before he was arrested at Recife International Airport, they tracked him across several Brazilian states, any one of which could have yielded the eggs.

Obviously, it’s much too late for Miyaki’s findings to affect the fate of this particular parrot trafficker, but her results show that this sort of analysis is continuing to emerge as a powerful tool for conservation. In Nepal, the Tiger Genome Project has consulted genetic material to see if the animals they’ve tagged are winding up on the black market as pelts and trophies. DNA data has also helped scientists pinpoint certain areas targeted by elephant poachers.

As Miyaki mentioned above, legal priority has been one thing standing in the way, but until recently, so has lack of data. When the man was caught by police in 2003, one of the genetic databases Miyaki consulted didn’t even exist yet. And even today, databases are only as robust as the material they contain. Luckily, parrots are well represented. But other clades are far less characterized, so the techniques may be less effective for cases involving woodpeckers or wading birds and the like.

Still, DNA analysis could potentially blow the door open for officials looking to hold traffickers accountable. Bush meat, bycatch, trophy hunting—it’s time to throw the book at those who want to make a buck off of pilfering endangered species. Preferably a nice big one, like the Sibley Guide to Birds.


onEarth provides reporting and analysis about environmental science, policy, and culture. All opinions expressed are those of the authors and do not necessarily reflect the policies or positions of NRDC. Learn more or follow us on Facebook and Twitter.

Join Us

When you sign up you'll become a member of NRDC's Activist Network. We will keep you informed with the latest alerts and progress reports.