We found the most vulnerable countries to be from Sub-Saharan Africa, while those countries representing the greatest threat to the rest of the world (given the invasive species they already contain, and their trade patterns) to be the United States and China.
Invasive species are capable of causing extinctions of native plants and animals, reducing biodiversity, competing with native organisms for limited resources, and altering habitats. This can result in huge economic impacts and fundamental disruptions of coastal and Great Lakes ecosystems.
1. Spotted lanternfly. Spotted lanternflies (Lycorma delicatula) are native to China but have run rampant all across the northeastern U.S., prompting experts to advise people to kill them. While they are harmless to humans and animals, they are a danger to over a hundred plant species.
The largest numbers are recorded in the intensive agricultural regions surrounding the major cities, such as the Sydney Basin, south-east Queensland, the Flinders Lofty Block and the Victorian midlands. We now have more introduced terrestrial plant species in Australia than native ones (Groves et al.
We found the most vulnerable countries to be from Sub-Saharan Africa, while those countries representing the greatest threat to the rest of the world (given the invasive species they already contain, and their trade patterns) to be the United States and China.
Most dormant invasive plants take an average of 40 years to become an issue. According to tracking data from the University of Georgia, 1,695 invasive or non-native plant species have been mapped in the California (No. 1) wilderness, the most in our ranking.
Invasive species are spreading in the Pacific Northwest at unprecedented rates due to large volumes of trade, tourism, and global climate change.
But many countries in South America, Africa and Southeast Asia have little capacity to prevent the introduction of invasive species and weak programs for reacting to invaders once they are present, leaving their natural resources at risk.
Tree-of-heaven (Ailanthus altissima), also known as Chinese sumac, is a deciduous tree native to northeast and central China and Taiwan. It was first introduced to North America in 1784 in Philadelphia, and became a popular ornamental tree commonly found in nurseries by the 1840s.
Zebra mussels negatively impact ecosystems in many ways. They filter out algae that native species need for food and they attach to--and incapacitate--native mussels. Power plants must also spend millions of dollars removing zebra mussels from clogged water intakes.
The domestic cat is often a beloved pet, but it's also a major threat to birds. Introduced to the United States with European colonists, the number of domestic cats has tripled in the past 40 years. Today, more than 100 million feral and outdoor cats function as an invasive species with enormous impacts.
Humans have effectively become an invasive species, taking over the homes and resources of animals across the globe. People continue to expand into new lands and territories to compensate for an ever-growing population, converting natural land into cities with homes, offices, shopping centers, and more.
The Pacific Islands are much more susceptible to invasive threats. Since the islands were buffered by extreme isolation throughout their evolutionary history, invasions can have a dramatic detrimental effect on ecosystems.
Invasive species are capable of causing extinctions of native plants and animals, reducing biodiversity, competing with native organisms for limited resources, and altering habitats.
The American bullfrog, native to the eastern US, is an invasive species in 40+ countries around the world, including parts of South America, the Caribbean, Europe, China, South Korea, and Japan.
Invasive species are primarily spread by human activities, often unintentionally. People, and the goods we use, travel around the world very quickly, and they often carry uninvited species with them.
Invasive species are spread primarily by human activities, often unintended. People, and goods transported, travel quickly around the world, and often carry uninvited species with them. Invasive species can be introduced to an area by ship ballast water, firewood, accidental release, and by people.
Ecological Threat
Many other wildflower fields across California and Arizona are now 75% occupied by Saharan mustard preventing wildflowers and other native shrubs from growing. During dry months Sahara mustard becomes and extreme fire hazard capable of spreading fire across sand dunes.
Invasive species frequently have strong negative impacts on fish populations and the fisheries they support. Sea lamprey, alewife, dreissenid mussels, round gobies, and the spiny water flea are all examples of invasive species that have affected or are affecting Great Lakes fisheries.