Every year, more than 100 million plants and animals are traded both legally and illegally around the world. But whether this is sustainable remains hotly debated among researchers. A study published July 26 in Nature sheds some light on the issue by creating a global map of ecosystem resilience to current levels of wildlife trade.
The findings could help conservation scientists and policymakers show where to focus resources by identifying hotspots where the wildlife trade could cause the most damage.
Author Oscar Morton, a conservation biologist at the University of Sheffield in the UK says It’s one thing to say, we know the trade is unsustainable, we know what happens to ecosystem X if we take out species A. For example, more than a million Tokai geckos (Gekko gecko) small, colorful lizards common in Southeast Asia are traded as pets each year. However, it is not known whether this volume of trade is sustainable.
Effects on the entire ecosystem
When measuring the overall sustainability of the wildlife trade, individual species cannot be considered in isolation, says Morton. Yet analyzing the impact of industry on ecosystems as a whole is so complex that few attempt it.
Morton and his colleagues addressed this gap by compiling data on legal trade in birds and mammals collected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and legal and illegal trade by the International Union for Conservation of Nature (IUCN). Scientists overlaid this information on maps of the distribution of different species around the world.
They added data on the species’ phylogeny their evolutionary history to indicate whether each had unique characteristics (see ‘Uniqueness Hotspots’). They also included information about the functional role of the species in the ecosystem for example, whether it is a large predator or a small herbivore. “In a healthy ecosystem, you want a wide range of traits, because then they’re performing all your ecosystem services that is, seed dispersal, carbon storage, pest control,” says Morton.
The resulting maps allow the team to visualize the potential impact of removing a species from an ecosystem.
Hornbills, for example, are widely traded for their mantles, the bony projections on their upper beaks. But as big fruit eaters, birds have a key role in seed dispersal in their ecosystems. If the hornbills were depleted from the area, the vegetation would change radically, with knock-on effects for the birds, insects and other animals that inhabit the ecosystem, Morton says.
Harmful business
The map revealed global hotspots where trade has the greatest potential for damage, i.e. ecosystems where functional and evolutionary diversity was high. “It’s an impressive piece of research that collects a huge amount of data,” says Vincent Nijman, a wildlife trade specialist at Oxford Brookes University in the UK. He says the map clearly shows that in relatively small areas of the world, industry could threaten ecosystems. It points to parts of Africa and Southeast Asia as important hotspots.
If we were able to pay more attention” to regulating trade in these regions, Nijman says, “then we will get a much better return on our investment.”
International and domestic policy should require assessing the impact of wildlife trade on entire ecosystems, Morton says. “When we talk about business sustainability, we should be looking at ecosystem sustainability as well as species sustainability,” he says.
As well as the role many species play in their ecosystems, it also has intrinsic scientific value, says University of Sheffield data scientist Mike Massam, co-author of the study. “We don’t want to lose millions and millions of years of evolutionary history.”
Written by: Vaishali Verma
