Yes. Because of the harm that invasive species can cause, they can reduce biodiversity and break the web of life.
An invasive species is an organism moved intentionally or accidentally by people or human activity from its native range to a new environment. Out of its native range, the species is only designated as invasive if it causes or is at risk of causing harm to the environment, the economy, or human health.
Many non-native species (e.g., agricultural crops) are beneficial and have shown no tendency to escape into the wild. By definition, a native species within its native range is not invasive, regardless of how vigorously it grows, reproduces or spreads, such as white-tailed deer and native grapes. Invasive species typically lack natural controls from their native ranges, such as herbivores, predators and pathogens.
Listed below are some examples of invasives that have generated headlines: Porcelain-Berry (vine), Spotted Lanternfly, Northern Snakehead, and Sudden Oak Death.
Judy Fulton
Bruce Moltzan, USDA Forest Service, Bugwood.org
Kp Rath, Shutterstock
Amy Lutz, Shutterstock
Are you seeing a new species in your area that you think might be invasive? Using the approach of "Early Detection and Rapid Response" is more effective than fighting a well entrenched enemy. LEARN MORE
Invasive species harm ecosystems by disrupting the delicate balance within the environment. Invasives compete with native organisms for limited resources (e.g., light, water, space and food) and degrade habitats. As a result, invasives can reduce populations and cause extinctions of native plants and animals, thereby lessening native biodiversity and ecosystem services essential to life and health. Invasives can also magnify the effects of climate change, including the impacts of erosion, wind, flooding and fires.
Besides contributing to natural disasters, invasive species can damage or decrease the productivity of crops, impede recreational and sports activities, and destroy infrastructure. By displacing natives species, invasives interfere with the important contributions that natives make to the economy.
A 2005 scientific article indicated that economic damages associated with invasive species-their impacts and control-totaled $120 billion per year in the U.S. (Pimentel et al., 2005). Since then the situation has continued to deteriorate. As a result, costs have risen due to the harm these nasty organisms are causing.
For example, the Asian tiger mosquito (Aedes albopictus) is a vector for equine encephalitis. Japanese barberry (Berberis thunbergii) infestations have been shown to more than triple the number of deer ticks (Ixodes scapularis) infected with the Lyme disease pathogen (Borrelia burgdorferi) (Williams et al., 2017).
Additionally, trees weighted down with invasive vines, like English ivy (Hedera helix) and oriental bittersweet (celastrus orbiculatus), can fall on people or structures. Feral pigs (Sus scrofa) can trample or gore people, and are now spreading far and wide throughout the U.S.
Native species occur in a particular place without human intervention. Species native or indigenous to the mid-Atlantic are generally recognized as occuring here prior to European settlement. Non-natives are species people introduced from other continents, parts of North America, ecosystems, or habitats. Many non-native plants and animals have great economic value for agriculture and other industries, and pose few environmental and human health threats. However, other non-native species have become invasive and are having serious negative impacts.
Photo: Judy Fulton 2019
Photo: Madamnoire, 2013, Wikimedia Commons
Native species are essential components of biodiversity and support life on Earth, as we know it. Massive extinctions of native species negatively impact civilization, and could threaten the continued existence of the human race. Natives have traits developed over thousands of years through coevolution with other plants, animals and the environment.
This complex web of life is crucial for ecosystem health, but can be thrown off kilter by invasives. Native species diversity increases ecosystem productivity, stability and sustainability, and so the quality of life for humans and other animals. The picture below shows how different life forms are interdependent, each component interacting with all other levels within the food web.
Download a PDF of the Food Web graphic
Plants are the most important building block of the food web, on which all life depends. Using the sun's energy, plants produce food (i.e. glucose) from carbon dioxide and water, and release the oxygen that animals breathe. Primary consumers—such as ungulates and many insects—eat plants, and these herbivores are in turn eaten by secondary consumers. These carnivores and omnivores are eaten by apex predators, such as humans and other large meat-eaters. When organisms die, they are decomposed into their basic elements by fungi, bacteria, protozoans and small invertebrates. By recycling dead organic material, decomposers create nutrients for plants, thereby continuing the cycle of life.
Healthy wild places and landscapes with natives provide crucial ecosystem services to the environment. For example, native plants help clean the Chesapeake Bay by filtering run-off, reducing erosion, and limiting the need for pesticides and fertilizers. Native plants increase the numbers and diversity of native pollinators, which in turn increases crop productivity. Native predators, such as dragonflies and songbirds, can reduce populations of nuisance insects, such as mosquitoes.
You can also look up other information, such as how and why species were selected for MIAT.