Invasive species have cost the global economy an annual mean amount of US$26.8 billion per year since 1970, with a threefold increase every decade, a new study has found.
Insects comprise some 90% of damage costs found by researchers, with vertebrates and plants rounding out the rest of the $1.62 trillion impact over the last 50 years on ecosystems, crops and fisheries. Specifically, the costliest invasive species were the tiger mosquito, followed by crop-eating rats, the Asian gypsy moth, and even domestic cats.
The worldwide implementation of efficient, coordinated control and mitigation strategies remains limited, according to researchers based in France, the Czech Republic and Australia. Their joint research paper is titled “High and rising economic costs of biological invasions worldwide”. The researchers hail from Université Paris-Saclay, Museum National d’Histoire Naturelle of Paris, Université de Montpellier and the University of South Bohemia.
“We found that costs roughly doubled every six years, a pattern that mimics the continuous increase in the number of alien species worldwide,” announced Professor Corey Bradshaw of Flinders University.
While Canada does not register as one of the harder hit countries on the study’s global map, invasive species are estimated to have cost it at least $22.8 billion since 1970.
Canada has been impacted significantly by the emerald ash borer, the brown rat, the gypsy moth and the Asian long-horned beetle. In the Great Lakes along the Canada-U.S. border, another $408.6 million in costs have been accrued from zebra and quagga mussels.
The researchers say that biological invasions should become a major factor when deciding transnational projects. They take place when species of animals, plants and pathogens are deliberately or accidentally introduced in regions not previously occupied by these species. One of the most contemporary examples is China’s ambitious Belt and Road Initiative that will open avenues for the introduction of new species around the world.
“That’s why we’re calling for international policy agreements that aim to reduce the burden of invasive species,” adds Professor Bradshaw.