Alien invasion: Study reveals alarming economic costs of biological invasions to the European Union

The European Union continues to be exposed to thousands of invasive alien species -- harmful species introduced by humans from outside of their natural habitat. The EU is particularly vulnerable because the region's volume of economic activity via trade and the transportation of goods increases the risks of biological invasions, according to the study published in Environmental Sciences Europe.

Most invasive alien species are not adequately assessed for their actual and potential economic impacts therefore most cost estimates are grossly underestimated, say the researchers. To fill this gap, the team quantified the economic costs of biological invasions to the European Union, while estimating future invasion costs using predictive models.

Costs potentially 501% higher than previously recorded

Their findings are alarming -- of the approximately 13,000 invasive alien species known to have established populations in the European Union, only 259 (around 1%) have reported costs, showing substantial knowledge gaps in cost assessments regionally. The researchers' models projected unreported costs to be potentially 501% higher than currently recorded, reaching a staggering €26.64 billion (US$28.0 billion) in the European Union, led by countries such as Lithuania, Malta, and Czech Republic.

The study's projections for future estimates revealed a substantial increase in costs, with estimates soaring to more than €142.73 billion (US$150 billion) by 2040 in the absence of effective management.

"Our study reveals a shocking underestimation of the economic costs of biological invasions in the European Union. These costs are not only a huge burden for the European Union's economy, but also jeopardise the ecological balance and well-being of societies," says lead author Morgane Henry, a PhD student under the supervision of McGill University Professor Brian Leung.

"It is imperative that we take immediate action to enhance cost reporting, identify the most concerning economic impacts, and work together on a global scale to address the threat posed by invasive alien species," she adds.

The researchers warn that policymakers, scientists, and stakeholders should take heed of the implications of the study and collaborate to protect ecosystems, safeguard biodiversity, and ensure the well-being of communities. Otherwise, biological invasions will create an insurmountable financial burden unless the EU and its governments take swift action to address the devastating ecological impact that's happening.

"The costs are potentially huge, but in most cases we just don't know. Notably, our fivefold increase in cost estimates included only 1% of species with existing data, by extrapolating to other countries where they are known to have invaded, but where costs have not been estimated yet. We don't know about the other 99% of the species," says Professor Brian Leung of McGill University's Department of Biology.