A Look at How Invasive Species Threaten Endangered Animals

There’s a fine balance in nature, as various environments support indigenous flora and fauna, creating conditions for these species to survive and thrive. However, when certain types of plants or animals arrive from elsewhere, it can create unwelcome changes. Let’s look at what defines an invasive species, how they might be introduced to a new location, and the kind of impact they can have on endangered species, humans, and the environment once they arrive.

Invasive species defined

Essentially, an invasive species is any sort of living organism that comes from another ecosystem. This could be an animal, disease, parasite, or plant. The other criterion is that their introduction must come with the potential to cause a degree of harm, such as to local populations of animals, plant life, the natural surroundings, or people.

What also makes these organisms invasive is their capacity to spread quickly and overtake the normal growth of species native to the locale. As they compete for resources, they begin to edge out the original organisms that depend on what the ecosystem offers for their survival. By definition, an invasive species doesn’t have to come from outside of the country, just from another location. 

Impact on endangered and threatened species

Would it surprise you to know that invasive organisms have put at risk the survival of about 42 percent of endangered or threatened species? Since these non-indigenous species have no natural predators in the area, they flourish and their numbers rapidly increase. The harm they do to native species includes overtaking them for resources like food, causing disease, killing their young, and interfering with their ability to reproduce.

Environmental damage

It’s been documented that invasive organisms can cause significant damage to food chains. They can replace or destroy food sources indigenous to the area and change the diversity of native species. When invasive plants grow aggressively, they leave less room for other species that the ecosystem and local wildlife depend on. Altering the habitat in this way can have a dramatic and devastating impact. There are actually invasive species capable of changing ecosystem conditions, including the chemistry of the soil and the intensity of wildfires. 

How spread occurs

Ordinarily, invasive species are spread by humans. This is usually quite unintentional, as people engage in various outdoor activities like fishing or gardening. They may unknowingly carry an invasive organism from one lake to another, or they might plant a lovely perennial in their flower bed without realizing that it can grow quickly and threaten native flora. People who have ornamental houseplants or keep exotic animals as pets might inadvertently allow them to escape and invade the local landscape. This is how Burmese pythons, for instance, have become a real issue in the Everglades.

And it’s not just individuals who bring non-native organisms into a different ecosystem. They can be introduced to a new habitat when they’re transported with goods shipped around the world. For instance, uninvited aquatic guests might come aboard large ships and reside in the ballast water or travel on the propellers of smaller vessels. Insects can be transported from one place to another in the wood of shipping crates or pallets.

Finally, nature plays a role in spreading invasive organisms, as well. As average temperatures rise with climate change and there are different rainfall and snowfall amounts, it sets the stage for certain species to move into another ecosystem. Plants weakened due to drought conditions, for example, are more susceptible to the ravages of an invasive species like the pine beetle.

Risk to human health

The health outcomes for people living where non-native species have been brought in can be challenging. Alien organisms may induce allergic symptoms or cause physical injuries. Another notable problem is that these species can carry infectious diseases that are harmful to humans. Exotic birds, insects, and rodents are able to bring pathogens to parts of the planet where they haven’t been before, promoting the emergence of new diseases. Additionally, attempts to eradicate invasive organisms with herbicides and pesticides can affect the health of residents when these substances get into the soil and water table.

Economic impact

The economic cost resulting from invasive species can add up fast. These pests can clog waterways, decimate crops, increase fire vulnerability, threaten fisheries, farms and ranches, and more. Critical infrastructures that supports communities with food and water security can be put at risk. The people who are most dependent on what nature provides are the first to be impacted. Globally, the cost to economies is quadrupling each decade with the most recent figure estimated at over $423 billion. The consequences can be insurmountable and exacerbated by other influences, such as climate change.

In closing

Ecosystems need to maintain a delicate equilibrium to preserve the indigenous population. When non-native organisms are introduced, the impact can be devastating, causing harm to humans and endangered animals, the environment, and the economy.