For the first time, scientists have quantified the extent of the global wildlife trade, finding that at least one in five land-based species is bought and sold on the world market, according to a new study published in the journal Science.
But that doesn’t mean the other four out of five species are safe. Up to 3,196 additional species are at risk of going extinct due to trade, the study predicts.
“We show that the proportion of species in the wildlife trade has the potential to grow, given current patterns. We could see one out of four or one out of three species traded in the future,” said Brett Scheffers, assistant professor at the University of Florida/IFAS and one of the study’s lead authors.
The researchers determined the proportion of globally traded animals by analyzing data on more than 30,000 land-dwelling species of mammal, birds, reptiles and amphibians.
The wildlife trade is the number one cause of species extinction, tied only with land development, Scheffers said. The wildlife trade includes animals traded as pets and animal products, such as horns, feathers or meat.
Whether an animal is part of the wildlife trade depends on its set of desirable traits. “Animals are valuable on the market because they have something special—for example, brightly colored birds are in demand, as are animals that are a source of ivory,” he said.
These desirable traits were the second focus of the study. Physical traits are determined by evolution, and tend to show up in clusters of related species. Desirable traits, too, will be concentrated in particular areas on the evolutionary tree of life.
And where these desirable traits are concentrated, so is trading activity, the researchers determined.
“If one species is traded, chances are its evolutionary cousins are also traded,” Scheffers said. “Once we discovered that pattern, we could develop a model that would predict which species would likely be traded in the future, even if they aren’t traded now.”
Researchers have already seen this trend in the trade of specific animals, but this study shows this pattern applies more broadly across the tree of life.
“Once one traded species is exhausted, species with similar traits will become the target of trade,” Scheffers said. “If we run out of one species of bright yellow bird, we move on to the next one most similar to it.”
These finding have the potential to reshape the current approach to wildlife conservation, the study’s authors said.
“Wildlife conservation is often reactive. Protections are put in place once a species is in danger, not before. Our model allows wildlife managers and policy makers to be proactive and keep an eye on the current and predicted future targets of the wildlife trade,” Scheffers said. “A species might not be of concern today, but as our study shows, that can change with shifts in supply and demand.”
The study’s findings can also help online platforms like Ebay and Facebook screen transactions for at-risk species.
While the use of big data to understand global wildlife trade may seem novel, the wildlife trade itself is nothing new. One wildlife trait, body size, has driven the wildlife economy for millennia, Scheffers said.
“Many researchers have argued that humans are the reason why many of the big Ice Age animals, like the wooly mammoth or the giant sloth, went extinct. It’s interesting that today body size is still a strong predictor of whether a species is traded,” Scheffers said. “However, the difference today is that we actively conserve species, and we hope this study provides the science to guide policy and management.”
The study was co-authored with Brunno Oliveira of Auburn University at Montgomery, and Ieuan Lamb and David Edwards of the University of Sheffield in the United Kingdom.