Most invasive species are spread accidentally by human activity

Florida: the invasive pythons capital of the world

As invasive pythons choke the life out of South Florida, it’s down to a loose-knit group of thrill-seeking bounty hunters to get rid of them.

Invasive species can harm infrastructure and threaten human health

The wildfires in Hawaii in 2022 were made worse by flammable invasive grasses introduced from Africa as livestock pasture, and Zebra mussels native to the Caspian and Black Seas have spread across Europe and the US, where they can clog power plant pipes. Invasive mosquitoes can carry diseases, such as dengue and malaria.

See photos of a 200-pound Burmese python is captured in Florida

Conservationist Mike Elfenbein and his son, along with three other hunters, captured a massive 198-pound Burmese python in Florida's Big Cypress National Preserve in the fall of 2023. See images of the hunters and their prey here.

Cane toads are an example of an intentional species introduction turned invasive

In 1935, Australian scientists imported several hundred cane toads to hunt and eat beetles that were damaging sugar cane fields. However, the toads could not reach the bugs at the top of the plant or the grubs in the soil. Instead, they negatively affected native species populations as their numbers grew to over 2 billion.

These invasive spiders are weaving their way across the US

The Joro spider was first spotted in the US in 2013 and has since spread throughout the Southeast. Get the 101 on this massive (and massively) invasive Asian spider in this article and infographics.

View some of the most invasive species in US waters

Introduced in the late 1600s from Eastern Asia, the goldfish is considered the first invasive fish in North America. The venomous lionfish is safe to consume, but catching it is complicated by its reluctance to respond to hook-and-line-style fishing attempts.

Benign species can become invasive if introduced into predator-free habitats

Most ecosystems contain organisms that, over many generations, have evolved into a stable balance with one another and their surroundings. In a new environment, a species may no longer be restricted by the limiting factors it is used to, and the native organisms in the area may not adapt quickly enough to the invader to establish a new balance.

Florida reports 71 imported malaria cases annually—4% of all the US cases

The Sunshine State reports an average of 71 imported malaria cases annually. Malaria isn't endemic to Florida but mosquitoes in the state are biologically capable of transmitting the disease from one infected person to another noninfected person.

The most effective method of managing invasive species is prevention education

Controlling a spread after a species has become established in an area is much more costly and time-consuming than early detection and rapid response. Control methods include the purposeful introduction of predators, the use of pesticides, herbicides, fungicides, and insecticides, and physical collection and removal.

Feral and free-ranging cats rank among the most harmful invasive species

Transported across the planet by humans, cats can now be found in many environments and are estimated to kill about 2 billion birds each year in the US. Studies suggest cats have contributed to the extinction of at least 63 species worldwide.

Increasing contact between humans and wild animals is driving zoonotic threats

Zoonotic diseases, which spread from animals to humans, present one of the most significant emerging threats worldwide. Scientists have identified around 200 viruses capable of infecting humans, and unfortunately, the number of such diseases are on the rise—at least 60% of all emerging infectious diseases are zoonotic in origin.

How scientists know invasive nutria were likely introduced to California by humans

Although native to South America, DNA testing of the semiaquatic rodents showed they are closely related to a population in Oregon, suggesting they were deliberately transported into the state. First identified in the San Joaquin Valley in 2017, the distance, terrain, and lack of nutria between the two regions has allowed researchers to rule out natural migration.

How Guam became an island of snakes and spiders

The US territory of Guam has 40 times the number of spiders of nearby islands, and a voracious collection of snakes which has nearly emptied it of any native birds. Researchers took it upon themselves to count the species and determine what turned the island into such a haunt of arachnids and serpents, where walking into the woods can mean navigating endless layers of spider webs. Find out more here.

Land use changes in Connecticut may have helped to enable Lyme's leap into humans

Forest clearing and fragmentation, alongside suburban development, may have contributed to the emergence of Lyme disease in humans in the 1970s. Those changes brought mice, carriers of the disease, into greater contact with people. Climate change is also facilitating Lyme's spread as tick populations survive milder winters and move northward.

West Nile virus found in the UK for the first time

The West Nile virus, which mainly spreads between birds and mosquitoes, was detected in the UK for the first time. While no evidence exists for any human infections, climate change may be expanding mosquitoes—and the diseases they carry—farther north.

Two invasive termite species are threatening Florida homes

Asian subterranean and Formosan subterranean termites have been found in northern and coastal counties, respectively. About half of all structures in the urban South Florida metropolitan area could be at risk of infestation by one or both species by 2040.

Canine inspectors can help detect potential carriers of invasive insects

At ports of entry in the US, Customs and Border Protection agents use dogs to sniff for forbidden foods and other items that are known to harbor invasive pests. Agents also physically inspect items such as flowers to prevent entry by species that may harm US agriculture.

Watch how viruses like Ebola can spill over from animals to humans—and vice-versa.

Ticks are extremely hard to kill

These arachnids can transmit more than a dozen diseases to humans, and they're very resilient: Some can survive extreme heat and cold, live for years without a blood meal, and even survive multiple days underwater.

The American cockroach is actually from Africa—an apparent hitchhiker aboard ships carrying enslaved people—with evidence suggesting it may have arrived in the New World as early as the 1600s

This podcast delves into the history of Periplaneta americana and explores why the bugs elicit such fear, disgust, and, at times, shame. The bug likely climbed aboard the slave ships because they had both unprotected food sources and places to hide during their journey.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

Explore a collection of galleries of pollinators found in national parks

Many of the photographs were taken during pollinator inventories in national parks across the US. Although these inventories often focus on bees and butterflies, the collection also features beetles, moths, spiders, and birds that transfer pollen as they move from bloom to bloom.

Dragonfly migration season is believed to run from August to November

Researchers know much less about dragonfly migrations than they do about bird or whale migrations. However, North America may have up to 18 migratory dragonfly species. A recent study revealed that the species undertakes complex long-distance migrations every year that span generations and seem to be influenced by temperature, making them particularly vulnerable to climate change.

Two marsupials thought to be extinct discovered in New Guinea

The pygmy long-fingered possum and the newly described ring-tailed glider were discovered in 2026 after scientists believed the species had been extinct for 6,000 years. The pygmy long-fingered possum is partially defined by its unusual trait of one finger on each hand that is twice as long as the others.

How flowering plants took over the world

Flowering plants are relatively young in the evolutionary scheme of things, only arriving after the dinosaurs had already been wiped out. Their evolution has long puzzled scientists, but recent research indicates their success is due to smaller,...

Humans are the only known reservoir of poliovirus

The virus has not been found in any other species, which makes humans the only known reservoir for polio. In laboratory settings, nonhuman primates have also been infected with the virus, but there's no evidence that they contract the virus in nature.

Why bananas are in trouble

The average American eats over 25 pounds of bananas every year, but we won't for long if a deadly soil fungus continues to spread. Learn what scientists are doing to save the popular fruit.

Some Pokémon have been named after real and fictional organisms, while some real-world species have been named after Pokémon, such as Chilicola charizard and Binburrum zapdos.

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

Poison ivy was sent to Europe in the 1600s as an exotic, ornamental oddity, where it was purposefully grown in the English royal gardens at Kew, the Faculty of Medicine in Paris, and a few other locations.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Planarian flatworms are small, aquatic worms with exceptional regenerative capabilities. When cut, the worms can regenerate multiple bodies in a matter of weeks.

When caught in the mouths of cardinal fish, seed shrimp release glowing, bioluminescent chemicals, which alert predators of the cardinal fish, prompting the shrimp's ejection.

About 12.5% of US adults experience a phobia in their lifetime, a diagnosis that hinges on the intense fear interfering with daily life and persisting for at least six months.

Explore fun facts from the USPS, including unique post office buildings, a stamp that traveled past Pluto, and more.

See this overview of the firework rules across all 50 states, ranging from a complete ban on non-professional fireworks in Massachusetts to states with more lax rules like Indiana.

In 2019, a laptop loaded with six of the worst malware in history and described as 'an exhibit of historical weaponry' sold for $1.3M.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

The concept of phantom limbs, the perception that amputated limbs are still present, dates back to a French military surgeon in the 16th century.

In 2009, the nation was gripped by the story of a missing young boy who was believed to be floating over Colorado in a homemade balloon, until it was revealed that he was at home the whole time.

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

The power and influence of the American presidency have expanded significantly over time—far beyond what the founders envisioned.

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

The Russia-Ukraine conflict is the largest ground war in Europe since World War II in casualties, forces mobilized, and displacement of civilians.

Telehealth demand for GLP-1s for weight loss is booming as consumers seek easier access.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

See how Budweiser's famous Clydesdales spend their days at Warm Springs Ranch, where roughly 70 to 80 of the beer brand's giant horses can be found at any given time.