Invasive species, long recognized as a global threat to biodiversity, have emerged as the leading cause of biodiversity loss in Australia, according to a comprehensive report released by the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES). The report sheds new light on the extensive impact of invasive alien species on ecosystems and underscores the urgent need for action.
The IPBES, a collaboration of 143 countries advising the United Nations, conducted the most extensive assessment of biological invasions to date. It revealed that invasive alien species pose a severe and often underestimated global threat, with over 37,000 alien species introduced to new regions worldwide through human activities, of which 3,500 are considered invasive, causing detrimental effects on biodiversity and local ecosystems.
Assessment co-chair Anibal Pauchard highlighted the gravity of the situation, stating that invasive alien species played a major role in 60 percent and were the sole driver in 16 percent of global animal and plant extinctions recorded. Moreover, at least 218 invasive alien species have contributed to more than 1,200 local extinctions worldwide. The economic cost of these invasions surpassed $655 billion annually in 2019 and has been escalating rapidly since 1970, with climate change further exacerbating the problem.
Australia, in particular, faces an alarming situation, with nearly 3,000 invasive alien species estimated to cost the nation approximately $25 billion annually in agricultural losses and management expenses, as explained by CSIRO chief research scientist for biosecurity Andy Sheppard.
The primary culprits behind biodiversity loss in Australia, according to Dr. Sheppard, are feral cats on land and European carp in rivers. European rabbits, while causing significant damage to agriculture, also remain a top concern. Notably, the most harmful invasive invertebrate is the red imported fire ant due to its adverse effects on human health, the environment, and agriculture.
The report emphasizes that there are effective measures to prevent and manage invasive alien species. However, it revealed that 45 percent of all countries do not invest in their management, and only 17 percent have national laws or regulations addressing the issue. Prevention is highlighted as the most cost-effective strategy, but eradication, containment, and control are also effective in specific contexts. Ecosystem restoration can enhance the resistance of ecosystems to future invasive alien species.
Despite the challenges, some success stories are noted, such as Australasia’s efforts in reducing the spread of the brown marmorated stink bug through strict border biosecurity and import controls. The report underscores the importance of preparedness, early detection, and rapid response in minimizing the establishment of alien species.
Dr. Sheppard stressed the need for coordinated action in Australia, urging collaboration with neighboring governments, sectors, NGOs, Indigenous peoples, and local communities to achieve the goal of preventing new extinctions. Federal Environment Minister Tanya Plibersek affirmed the government’s commitment to addressing invasive species as a top priority, noting the devastating impact of feral cats and their role in two-thirds of mammal extinctions over the past two centuries. Measures and funding initiatives are in place to combat this critical issue, as part of the Threatened Species Action Plan and the National Heritage Trust.
