Invasive Species

From cane toads to kudzu, invasive species (sometimes called alien species) are those that aren't native to an ecosystem and that cause harm to native species, local economies or humans. Invasive species can be terrestrial species, like the pythons invading Florida's Everglades, marine, like the lionfish invading Caribbean waters, or pathogens. Invasive species can cause harm by out-competing native species, or preying on them. They can sometimes increase fire risks or contribute to erosion. Some invasive species have been introduced accidentally and others, like kudzu, were introduced on purpose and then spread more widely than originally intended. Invasive species are found in every type of habitat and are typically difficult to eradicate. Read more about invasive species around the globe and efforts to stop their spread.

Related Topics: Biodiversity, Insects, Planets

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Tawny crazy ants (Nylanderia fulva) are so named because of their quick and unpredictable movements.

Invasive crazy ants are being annihilated by murder fungus. Good.

By Mindy Weisberger published

Crazy ant colonies in North America are being driven to extinction by a fungus that targets the invasive pest species.

several giant african land snails in green grass; two are mating in the foreground

Giant snails that were eating Florida homes finally eradicated … again

By Nicoletta Lanese published

The cane toad (Rhinella marina) is an invasive species in Australia, where its tadpoles have become voracious cannibals.

Cannibal toads eat so many of their young, they're speeding up evolution

By Laura Geggel published

Competition is so fierce Down Under, the invasive cane toad has become a mega-cannibal.

Adults of the Asian giant hornet can be distinguished from other hornets by their big “cheeks” (which hold muscles for savage biting), teardrop-shaped eyes and a scalloped structure above the mandibles in between the eyes.

Invasive 'murder hornets' are officially back in the US

By Jeanna Bryner published

An invasive and destructive "murder hornet" has been spotted in Washington state for the first time this year, and the alien-looking insect was behaving accordingly — attacking a hive of paper wasps.

One of the enormous fish discovered in Lake Keller.

Football-size goldfish are taking over US lakes

By Ben Turner published

They can grow up to 1.5 feet and survive for more than five months without oxygen.

An invasive jumping worm spotted in Wisconsin.

'Crazy worms' have invaded the forests of 15 states, and scientists are worried

By Brandon Specktor published

Highly invasive jumping worms or 'crazy worms' have been found in 15 states, and they are only poised to spread more, scientists warn.

Wildlife biologist Jenny Ketterlin Eckles and wildlife technician Edward Mercer, both with the Florida Fish and Wildlife Conservation Commission, hold a Burmese python during a press conference in the Florida Everglades about the non-native species on Jan. 29, 2015 in Miami, Florida.

Would you eat a python to save the Everglades?

By Patrick Pester published

Invading pythons are causing problems for the native wildlife in Florida. Should people start eating them and are they even safe to eat?

An image shows a murder hornet's distinctive face.

Here's how to tell a 'murder hornet' from other nasty wasps

By Rafi Letzter published

A new paper gathers images of invasive Vespa hornet species worldwide, and offers clues to help identify them.

Flushed Goldfish Grew to Be Kitten-Size in Niagara River

By Mindy Weisberger published

Tens of millions of "freed" goldfish are thought to inhabit the Great Lakes.

python in Florida

Captured 17-Foot-Long Python Was About to Have 73 Babies

By Laura Geggel published

Lionfish, which have no natural predators in the Atlantic, threaten reef systems by preying on fish that clean the reef and keep it healthy.

Lionfish: Beautiful and Dangerous Invaders

By Nicoletta Lanese published

Lionfish are known for their breathtaking beauty, venomous sting and relentless invasion of tropical waters far from their native habitat.

bobcat, urban bobcat

Show-Off Bobcat Walks in Front of Tourists with a Dead Iguana Dangling from Its Mouth

By Brandon Specktor published

This iguana never stood a chance.

Green shore crab (Carcinus maenas).

Mutant Green Crabs Are Mean, and They're Invading Maine's Waters

By Stephanie Pappas published

Fearless crabs threaten the state's shellfish industry.

Newly Discovered Hybrid Pythons Could Threaten Florida's Everglades

By Yasemin Saplakoglu published

The hybrids could harbor more robust genes that allow them to adapt to various types of environments.

Sea pickle

Tropical Pink 'Sea Pickles' Are Invading the Waters of the Pacific Northwest

By Kimberly Hickok published

It's a totally tubular invasion.

Wild parsnip flowers.

This Woman Stumbled into a 'Hobo Parsnip' Plant. Days Later, Her Legs Were Severely Burned.

By Kimberly Hickok published

When plants fight back, the results can be pretty painful.

This Towering Plant Is Invading the US, and It’s Causing Serious Sunburns

By Yasemin Saplakoglu published

How does a plant cause sunburn?

he Crest-tailed Mulgara was once commonplace in the Australian desert, but had declined to the appearance of extinction under pressure from invasive species.

A Tiny, 'Extinct' Marsupial Re-Emerges in the Australian Desert

By Rafi Letzter published

A species of tiny, adorable marsupial that scientists thought had been extinct for more than 100 years has re-emerged in New South Wales, Australia.

Japanese mussels (<em>Mytilus galloprovincialis</em>), barnacles (<em>Megabalanus rosa</em>) and sea anemones attached to a tsunami buoy washed ashore on Long Beach, Washington, in February 2017.

Marine Invaders: Japanese Tsunami Brought 300 Species to US Shores

By Megan Gannon published

Plastic made the mass migration possible.

lionfish

'Twilight Zone' Horror Story: Lionfish Prey on Unknown Fish Species

By Stephanie Pappas published

Fish unknown to science are being scarfed down by an invasive species.