The world is losing the war against invasive species

Invasive species that destroy cropsdevastate forestsspread diseases and disrupt ecosystems, are spreading faster and faster around the world and humanity has failed to stop them, an international scientific body warned Monday.

This situation is costing more than US$ 400 billion a year in damages and lost income, the equivalent of the GDP of Denmark or Thailand, a figure probably underestimated, indicates the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES). ), sponsored by the UN.

Invasive species range from the water hyacinth choking Lake Victoria in Africa to brown rats and snakes wiping out bird species in the Pacific, to mosquitoes carrying Zika, yellow fever and dengue fever to new regions. .

There are 37,000 exotic species in the world, of which slightly less than 10% can be considered “invasive” and “harmful” for the effects “negatives” or even “irreversible” they have on ecosystems and on the quality of life on Earth, according to the report.

Economic development, population growth and climate change “will increase the frequency and scope of biological invasions and the impacts of invasive alien species”indicates the report, and only the 17% of countries have laws or regulations to deal with this attack.

Whether by accident or on purpose, when non-native species end up on the other side of the world it is always the responsibility of humans, according to scientists.

Its spread shows that the rapid expansion of human activity has radically altered natural systems and has led the Earth to a new geological epoch, the Anthropocene, experts say.

Rabbits in New Zealand

In Africa, the hyacinth that came to cover the 90% from Lake Victoria, crippling transport and suffocating aquatic life, was introduced by Belgian colonial officials to Rwanda as an ornamental flower. But in the 1980s it made its way up the Kagera River.

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

In New Zealand, English settlers brought rabbits in the 19th century to hunt and eat. When they began to multiply they imported stoats, a small carnivore, to reduce their numbers.

But the stoats decided to attack endemic birds, such as the kiwi or the one-eyed plover (‘ngutuparore’ in Maori) that were soon decimated.

New Zealand and Australia are “exemplary cases” how it’s a mistake to try to control one imported pest with another, Elaine Murphy, a scientist at the New Zealand Department of Conservation, told AFP.

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

Largely due to the enormous 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, the IPBES report indicates.

In the Hawaiian archipelago, the fire that swept through the town of Lahaina on the island of Maui last month was fueled in part by dried plants, a species imported decades ago to feed livestock but later spread to the abandoned sugar plantations.

In December, an international treaty to protect biodiversity was approved in Montreal (Canada), which includes the goal of halving the rate of spread of invasive alien species by 2030.