Study: Invasive Species Cost Earth $423 Billion Every Year

What do kudzu vines choking off a native oak tree in North Carolina and blue crabs killing shellfish off the shores of Italy have in common? They're both invasive species. They, and others, do great harm to native ecosystems. Last week, the United Nations (UN) put a price tag on that damage. $423 billion per year.

The UN defines an invasive species as a plant or animal from one ecosystem that has been moved elsewhere. It also states these species have harmful impacts on nature. They hurt biodiversity, local ecosystems, and native species. The so-called “murder hornet'' is one example. It attacks honeybees in the Pacific Northwest. But it comes from southeast Asia.

A key study was published last Monday. In it, experts analyzed the global impact of invasive species. They estimated the cost of damage these species have caused. They found it quadrupled each decade since the 1970s.

Helen Roy is an ecologist. She is also a study co-leader. “We are seeing unprecedented increases in the numbers of alien species worldwide,” Roy told The New York Times. “It’s about 200 new alien species every year.  And, yes, with those kinds of numbers, we will also see the impacts increasing.”

The report was compiled by 86 experts. They come from 49 countries. They used data from thousands of independent studies. They found evidence of more than 37,000 invasive species worldwide. Almost all of the species were moved because of humans' actions.

Peter Stoett is an environmental expert. “The problem is growing," he stated. But he also said it's a problem humans can still reverse. People simply have to work hard at it.

Reflect: What do you think are some of the challenges we might face in trying to protect native ecosystems from invasive species?