Context: With the rise in the spread of invasive species, the world has seen economic damages quadruple every decade since 1970, the UN Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) noted, in its findings.

Key Findings of the IPBES Assessment Report

• According to a major new report by the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), more than 37,000 alien species have been introduced by many human activities to regions and biomes around the world. This conservative estimate is now rising at unprecedented rates. 

• More than 3,500 of these are harmful invasive alien species – seriously threatening nature, nature’s contributions to people and good quality of life. Too often ignored until it is too late, invasive alien species are a significant challenge to people in all regions and in every country.

• The repor said that invasive alien species are one of the five major direct drivers of biodiversity loss globally, alongside land and sea use change, direct exploitation of organisms, climate change, and pollution.

• The report has noted that the number of alien species (species introduced to new regions through human activities) has been rising continuously for centuries in all regions, but are now increasing at unprecedented rates, with increased human travel, trade and the expansion of the global economy.

• Not all alien species establish and spread with negative impacts on biodiversity, local ecosystems and species, but a significant proportion do – then becoming known as invasive alien species. 

• About 6% of alien plants; 22% of alien invertebrates; 14% of alien vertebrates; and 11% of alien microbes are known to be invasive, posing major risks to nature and to people.

• Nearly 80% of the documented impacts of invasive species on nature’s contribution to people are negative.

• The report further noted that many invasive alien species have been intentionally introduced for their perceived benefits, “without consideration or knowledge of their negative impacts’’ – in forestry, agriculture, horticulture, aquaculture, or as pets.

• Invasive alien species like Aedes albopictus and Aedes aegyptii spread diseases such as malaria, Zika and West Nile Fever, while others also have an impact on livelihood such as the water hyacinth in Lake Victoria in East Africa led to the depletion of tilapia, impacting local fisheries.

• The IPBES report has further warned that warming temperatures and climate change could favour the “expansion of invasive species’’.

• “Climate change is also predicted to increase the competitive ability of some invasive alien species, extending the area suitable for them and offering new opportunities for introductions and establishment. Invasive alien species can also amplify the impacts of climate change.

Key Impact

• Invasive alien species (IAS)  led to a loss of more than $423 billion in 2019 and the report points out that they are among the five top drivers of biodiversity loss along with changes in land-and sea-use, direct exploitation of species, climate change and pollution.

• The report also shows that 45 per cent of all countries do not invest in the management of biological invasions. 

• At present 34 per cent of the impacts of biological invasions are in the Americas, 31 per cent in Europe and Central Asia, 25 per cent in Asia and the Pacific and only about 7 per cent in Africa.

• Most negative impacts are reported on land (about 75%) – especially in forests, woodlands and cultivated areas – with considerably fewer reported in freshwater (14%) and marine (10%) habitats . Invasive alien species are most damaging on islands, with numbers of alien plants now exceeding the number of native plants on more than 25% of all islands.

• Most countries (80%) have included targets related to managing invasive alien species in their national biodiversity plans. Only 17% specifically address the issue in national legislation, although more (69%) include it as a part of legislation in other areas. Nearly half of all countries (45%) do not invest in management of biological invasions.

How big is threat of invasive species?

• “Invasive alien species are a major threat to biodiversity and can cause irreversible damage to nature, including local and global species extinctions, and also threaten human wellbeing,” wrote Roy, Professor Anibal Pauchard and Professor Peter Stoett, who led the research. 

• The researchers also noted that while “specific species that inflict damage vary from place to place, these are risks and challenges with global roots but very local impacts facing people in every country, from all backgrounds and in every community – even Antarctica is being affected.”

• “Invasive species are affecting not only nature but also people and causing terrible loss of life,” said Pauchard who is also the report co-chair. 

• One of the most recent examples of this is the wildfires in Hawaii last month which claimed the lives of at least 115 people and are said to be driven by flammable invasive grasses which, scientists say, were brought over from Africa as livestock pasture. 

• According to Roy, invasives can show up in several forms, including microbes, and invertebrates but plants, and animals often have the greatest environmental impact, particularly predators. 

Key Suggestion

• Once introduced and established in an environment, getting rid of invasive species is difficult. While some small islands have witnessed some success in eradicating invasive rats and rabbits with trapping and/or poisoning; larger populations pose a challenge. 

• The report also noted that only 17 per cent of countries have measures, laws or regulations to manage this onslaught of invasive species. 

• “Birds in New Zealand had no experience with rats until humans came and brought rats. Their nests are at ground level,” said Pauchard, speaking about how many island species had previously evolved without predators which made them “very naive”. 

• Meanwhile, invasive plants often reportedly leave their seeds lying dormant in the soil for years. 

• Therefore, the IPBES outlines general strategies to combat invasive species which include prevention, eradication and then, failing that, containment. However, prevention measures through border biosecurity and import controls are most effective, said the scientists. 

• In a bid to save biodiversity, at least 190 countries have committed to placing 30 per cent of land and water under protection by 2030, in line with a global treaty hammered out in Montreal last December. 

• The Kunming-Montreal Global Biodiversity Framework also aims to reduce the rate at which invasive alien species spread by half by 2030. 

About Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) 

• It is an independent intergovernmental body. It aims to strengthen the science-policy interface for biodiversity and ecosystem services for the conservation and sustainable use of biodiversity, long-term human well-being and sustainable development. 

• It was established in Panama City, on 21 April 2012 by 94 countries. It is not a United Nations body. However, at the request of the IPBES Plenary and with the authorization of the UNEP Governing Council in 2013, the United Nations Environment Programme (UNEP) provides secretariat services to IPBES.

• It currently has close to 140 member States. A large number of NGOs, organizations, conventions and civil society groupings also participate in the formal IPBES process as observers.

What does IPBES do?

The work of IPBES can be broadly grouped into four complementary areas:

• Assessments: On specific themes (e.g. “Pollinators, Pollination and Food Production”); methodological issues (e.g. “Scenarios and Modelling); and at both the regional and global levels (e.g. “Global Assessment of Biodiversity and Ecosystem Services”).

• Policy Support: Identifying policy-relevant tools and methodologies, facilitating their use, and catalyzing their further development.

• Building Capacity & Knowledge: Identifying and meeting the priority capacity, knowledge and data needs of our member States, experts and stakeholders.

• Communications & Outreach: Ensuring the widest reach and impact of IPBES’s work.