Volunteers remove invasive verbesina encelioides (golden crownbeard) plants at Midway Atoll National Wildlife Refuge in the Pacific.

Invasive species are non-native plants, animals and other living organisms that thrive in areas where they don’t naturally live and cause (or are likely to cause) economic or environmental harm, or harm to human, animal or plant health. Invasive species degrade, change or displace native habitats, compete with native wildlife, and are major threats to biodiversity.

The origin and effects of invasive species invasive species
An invasive species is any plant or animal that has spread or been introduced into a new area where they are, or could, cause harm to the environment, economy, or human, animal, or plant health. Their unwelcome presence can destroy ecosystems and cost millions of dollars.

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vary. Many invasive species are spread or introduced accidentally, on the hulls of boats or soles of shoes, for example. Some are purposely acquired pets or garden trees or flowers that end up in the wild. Invasive fish and wildlife can prey on native animals and outcompete them for food and habitat. Invasive plants can outcompete native vegetation for space, moisture, sunlight and soil nutrients.

Although invasive species occur on all continents, islands experience disproportionate impacts. Islands make up just 5.3 percent of Earth’s land area, but they are biodiversity hot spots — home to a host of species. Unfortunately, islands also see the greatest concentration of species extinctions. About 75 percent of all reptile, bird, amphibian and mammal extinctions have occurred on islands. Invasive species have played a role in most of them.



Details about invasive species