Invasive species cause losses of US$ 400 billion a year – 09/04/2023 – Environment

The invasive species that destroy crops, devastate forests, spread diseases and alter ecosystems are increasing faster and faster all over the world, and humanity has not been able to contain them, warned this Monday (4) an international scientific body.

This situation is costing more than US$ 400 billion dollars (R$ 1.972 trillion in current exchange rates) per year in damages, equivalent to the GDP of Denmark or Thailand, a number that is probably underestimated, indicates the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), supported by the UN.

Invasive species range from the water hyacinth, an aquatic plant that suffocates Lake Victoria, in Africa, to rats and brown snakes that exterminate bird species in the Pacific, to mosquitoes that carry zika, yellow fever and dengue to new regions.

There are 37,000 exotic species in the world, of which just under 10% can be considered invasive and harmful due to negative or even irremediable effects on ecosystems and the quality of life on Earth, according to the report.

Economic development, population growth and climate change “will increase the frequency and extent of biological invasions and the impacts of invasive alien species”, the document states, and only 17% of countries have laws or regulations to combat this attack.

Whether by accident or design, when non-native species end up on the other side of the world, humans are always to blame, the scientists point out.

The propagation shows that the rapid expansion of human activity has radically altered natural systems and led the Earth into a new geological epoch, the Anthropocene, experts also say.

rabbits in new zealand

In Africa, the water hyacinth, which once covered 90% of Lake Victoria, paralyzing transport and suffocating aquatic life, was introduced by Belgian colonial authorities to Rwanda as an ornamental flower. In the 1980s, it reached the Kagera River.

Another case is the Everglades, in Florida (United States), full of descendants of ancient pets and domestic plants, from five-meter Burmese pythons to climbing ferns from the Old Continent.

English settlers brought rabbits to New Zealand in the 19th century to hunt and eat. When the animals began to multiply, they imported stoats, a small carnivore, to reduce their numbers. However, the stoats decided to attack endemic birds, such as the kiwi or the one-eyed plover (“ngutuparore”, in Maori), which were quickly decimated.

However, in many cases, the arrival of invasive species is an accident, as in the Mediterranean Sea, full of fish and non-native plants, such as lionfish and algae nicknamed “killers”, coming from the Red Sea through the Suez Canal. .

Largely due to large volumes of trade, Europe and North America have the world’s highest concentrations of invasive species, defined as those that are non-native, cause damage and appear due to human activity, indicates the IPBES report.