'Biological Pollution' Threat To Developing Countries

Sep 3, 2016

The yellow star-thistle is native to the Mediterranean Basin, but it's an invasive species in California, where there are no herbivores to eat it. So, the star-thistle will take over fields and its spikes prevent native animals from grazing or migrating.
Credit Jeffrey Dukes, Purdue University

Researchers from Purdue and other universities published a major global analysis of invasive species threats. The study found invasive species will primarily endanger developing countries.

Jeff Dukes, a Purdue University biology and forestry professor, calls invasive species plants or animals that have invaded an area they’re not native to.

“Invasive species are basically a form of biological pollution and it’s like biological pollution that doesn’t just sit there, it sort of explodes on you,” says Dukes. “They’re species that have evolved somewhere else, they’re new to an ecosystem and have real, negative consequences for the ecosystems that they enter.”

For example, Dukes says Indiana is dealing with problems from honey suckle shrubs. Originally brought here as decorative plants, he says they grow on the ground in forests and choke out tree saplings.

The study found that countries with fragile economies, like Niger, Chad and Mongolia, are especially vulnerable to invasive species. “We get a lot of benefits from nature that we sometimes take for granted,” says Dukes, benefits like fishing and agriculture.

“There’s very little margin for error for farmers in the developing world, much less than there is here,” says Dukes.

The study was published in the journal Nature Communications by researchers from Purdue and 13 other institutions.