Experts have identified a tipping point at which the rapid spread of invasive species will cause major biodiversity loss. The researchers found that a 20 to 30 percent increase in non-native plants and animals will result in the loss of many native species worldwide.
Human activities such as global trade and transport are increasingly moving species into regions where they are not usually found. Invasive plants and animals can cause major problems in their new habitats, where they compete with native wildlife for food and often trasmit diseases.
While the historical movement of invasive species has been well-studied, the potential magnitude of this issue – as well as the future consequences – are largely unknown.
The current study was conducted by 38 researchers from Europe, North and South America, New Zealand and South Africa. The international team was led by Franz Essl and Bernd Lenzner of the University of Vienna.
“At the moment it is not yet possible to generate precise predictions based on computer models as to how the spread and impact of alien species will change in the future,” said Essl. “Therefore, expert assessments via standardized surveys are an important tool to obtain a better understanding of the causes and consequences of the spread and impact of alien species for the coming decades.”
The experts determined that when 20 to 30 percent more invasive species become established, which could happen in the near future, a large amount of wildlife will be completely phased out of their native habitats.
According to the study findings, humans are the driving force behind the introduction of invasive species in three main ways: the increasing global transport of goods, human-induced climate change, and economic development including land use changes.
“There has been a rapid escalation in the number of non-native species being transported and introduced by humans around the world; the adverse effects of some of these so called invasive non-native species on biodiversity and ecosystems has been extensively documented,” said study co-author Helen Roy of the UK Centre for Ecology & Hydrology.
“It is now critical that we work collaboratively to predict future patterns so that we can inform appropriate action going forward – such as improved biosecurity to prevent further introductions of the most damaging invasive non-native species.”
The study is published in the journal Global Change Biology.