The scope of the threat posed by invasive species is something like the forest versus the trees analogy. It is easy to focus on the specific threat and miss the broad picture. Apparently invasive species threaten Earth’s entire eco-system.
According to New Scientist the threat is very large indeed. Some estimates place the number of invasive species worldwide at about 37,000 with about 10 percent of them causing great harm.
New Scientist said:
“This is a huge, huge problem, and it is a growing problem,” says Helen Roy at the UK Centre for Ecology & Hydrology, one of 90 researchers who helped put the report together.
However, the report also says that much can be done to tackle the issue and prevent further introductions. Individuals can help as well as governments, says Roy. “People all around the world can make a difference.”
People can take steps to ensure they don’t help invasive species to spread and can also report the presence of invasive species to help eliminate them or prevent them from becoming established in the first place. For instance, she says, reports by members of the public in the UK are helping to ensure that any nests of Asian hornets are promptly destroyed, which has so far prevented the species from becoming established in the country.
Human activities have resulted in the introduction of 37,000 alien species around the world, with 3500 of those species responsible for serious harm to wildlife, food production and human health. The global economic cost of these invaders is now more than $420 billion a year, according to the first major global report on invasive species, by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).” (links in original).
The IPBES report can be linked here.
In the United States Texas and Florida are among the hardest hit. Destructive ants, wild pigs, various kinds of snake and eels are among the transgressors. Worldwide, Australia is also hard hit. Feral cats and a host of other invasive species threaten the Australian eco-system.