How Invasive Species Impact Our Environment?
What are Invasive Species?
Animals or plants from another section of the world that do not belong in their new environment are considered invasive species. They can enter an area through ship ballast water, accidental release, and, most commonly, people. Invasive species can impact the environment by causing the loss of native plants and animals, the destruction of biodiversity, and permanent alteration.
Invasive species can impair both natural resources and human usage in an ecosystem. It can enter a new location through the ballast water of ocean-going ships, purposeful and unintentional discharges of aquaculture species, aquarium specimens or bait, and other sources. Invasive species have the potential to extirpate native plants and animals, reduce biodiversity, compete with native organisms for limited resources, and modify environments. This can have significant economic consequences and fundamental disturbances to the coastal and Great Lakes ecosystems.
Where do invasive species come from?
Invasive organisms can penetrate new ecosystems through a variety of channels. Some are purposely brought to new regions and established but with unintended consequences. Beach vitex was planted as an attractive plant for coastal residences in coastal North Carolina in the 1980s. However, once established, the plant began to supplant native species. The plant also lacks the vast root system that native plants have for holding sand in place. As it spreads, the plants speed dune erosion by destroying vegetation that holds the dunes’ sands in place.
Some invasive species were introduced due to failed attempts to control others. Rats that arrived on ships in the Virgin Islands swarmed the sugar cane plantations, causing severe crop damage. Farmers introduced mongoose as a predatory control for rats. However, because rats are nocturnal and sleep in trees, and mongooses are diurnal and cannot climb trees, they could not eradicate the rats. As a result, the islands now have to deal with two invasive species.
Other species are purposely transported to distant locations but mistakenly released, as is occasionally with animals in zoos and aquariums. Lionfish are thought to have arrived in the Caribbean after escaping from a shattered seaside aquarium after Hurricane Andrew in 1992. When people no longer desire to care for their exotic pets, they may sell them. This has been the situation with invasive Burmese pythons in the Everglades. These were previously popular pets due to their brilliant colors and easygoing demeanor. They can, however, grow up to 6 feet in the first year and live for more than 20 years.
What is the impact of invasive species?
Invasive species can have a variety of detrimental effects on the environments they inhabit. The widespread loss of habitat is the most serious of these. The hemlock woolly adelgid is an invasive Asian bug that kills afflicted hemlock trees quickly. It is estimated that up to 80% of hemlock trees have been killed in some sections of the Eastern United States. Many creatures rely on these woods for habitat; if they disappear, species that depend on them may become extinct.
Similarly, the health of many kinds of wood is threatened by kudzu vines, which were introduced in Japan as an aesthetic plant in the nineteenth century. This plant was widely dispersed throughout the Southeastern United States as an erosion control and grazing animal food source. However, the vine quickly became widespread and can fully overgrow entire forests. It effectively kills the forest by preventing sunlight from reaching the trees. Furthermore, the weight of the thick vine mats on trees might cause them to crack and tumble over. Because of its capacity to quickly overgrow and destroy forests, it has acquired the moniker “the vine that ate the South.”
In addition to devastation, sure intruders can physically alter the habitat. In 1946, 50 Canadian beavers were moved to Tierra del Fuego, an archipelago off the southern tip of South America, to be hunted for their pelts. They have since expanded and currently number in the hundreds of thousands. The trees in the region are not suited to beaver activity like they are in North America, and most do not regrow after being gnawed by beavers. Parts of the once pristine forests now appear plowed through by a bulldozer. Beaver activity also causes ponds, which flood parts of the woods. These basins of stagnant water disrupt the nutritional cycle in forests, allowing exotic species to thrive. Beavers also form dams in grassland drainage ditches, and cattle frequently fall into them, becoming trapped and dying.
Other invasive species may not harm habitat, but they can have an impact by causing the extinction of many endemic species. Burmese pythons, for example, are among the most dangerous predators in the Everglades. As a result, they have wiped out the local mammal and bird populations. These monsters, capable of swallowing deer and even alligators, eat almost any animal in the Everglades. Several fragile and endangered bird species have also been discovered in python digestive tracts, raising concerns that they may drive certain species to extinction. Lampreys parasitize native fish in the Great Lakes.
Because the native species have not evolved lamprey defenses, they frequently die from wounds, or the scars grow infected and eventually cause death. Invasive species can potentially endanger native species by vying for resources. Asian carp brought into the United States compete with local fish for food and space, significantly decreasing native fish populations. In the United States, invasive species are the second leading cause of extinction.
Invasive species can affect human health. Toxins such as PCBs and PAHs are accumulated in the tissues of invasive zebra mussels. Toxins are transferred up the food chain when other creatures hunt on these mussels, and they can also infect animals ingested by humans. Ship ballast water can potentially include dangerous microorganisms such as cholera. Invasive animals can also act as disease vectors.
In addition to these consequences, invasive species can impose significant economic expenses. In the Great Lakes, zebra mussels can quickly blanket submerged surfaces, obstructing water intakes at water treatment facilities and power plants. Removing this invasive species will cost $500 million annually in the Great Lakes alone. Power providers spend an estimated $1.5 million each year to control kudzu vines that grow on power wires. Lampreys have destroyed numerous fisheries stocks in the Great Lakes to the point where they are no longer lucrative. In the United States, invasive species are expected to cost $120 billion yearly in control methods and environmental resource loss.
The Bottom Line
Invasive animals are one of the most severe dangers to native biodiversity. It harms around 42% of vulnerable or endangered species. Invasive organisms endanger both human health and the economy. Each year, the effects of invasive species on our natural ecosystems and economy cost billions of dollars. Various commercial, agricultural, and recreational activities rely on healthy native ecosystems. Invasive species impact animals in a variety of ways. A novel, aggressive species may be introduced into an ecosystem without natural predators or restrictions. It can swiftly reproduce and spread, taking over an area.
Native fauna may not have evolved defenses against the intruder, or they may be unable to compete with a predator-free species. Invasive species pose direct hazards to native species by preying on them, competing with them for food or other resources, spreading or carrying disease, and preventing native species from breeding or killing their young.