It’s National Invasive Species Awareness Week, which means it’s time to draw attention to the problem of invasive species and how best to address the issues they cause. First, what is an “invasive species”? This term describes animals, plants and fungi that are “non-native”, meaning they were introduced into an environment where they do not naturally occur. Invasive species often cause problems by overtaking the native animal and plant populations, and disrupting the ecological balance, particularly when they are unchecked by natural predators.
There are many ways in which a particular species can travel from its natural region of origin to a new, non-native habitat. Often, in the case of animals in particular, humans are involved. Sometimes, the species are transported unknowingly. Several species of rat have been introduced throughout the world by traveling alongside humans on ships, crossing oceans that the rats would otherwise have no way of getting across.
In other instances, the introduction of a species is intentional, for various and often misguided reasons. For example, a man named Eugene Schieffelin introduced the European starling to North America by releasing 100 of these birds in New York’s Central Park in the 1890s. His goal was apparently to introduce all the birds featured or mentioned in William Shakespeare’s plays to North America. Because of one man’s actions, it is now believed there are well over 200 million starlings in the United States, with many negative consequences for the ecosystems they have invaded.
Many species become so widespread that it is almost forgotten that they aren’t native in the first place. The large mouth bass, a fish native to North America, was brought to other countries due to its popularity as a sport fish, but has caused harm to local native fish populations all over the world. Another type of fish, the common carp, is native to Europe but was long ago brought to other countries to be farmed for food. They are now found virtually everywhere except for the extreme north and south poles. Despite being so widespread throughout the world, it is ironically endangered in its native habitat. The Asian carp is another extremely invasive species that was originally intended to control algae in fish ponds, but was able to escape into other lakes and rivers in times of flooding and spread invasively to environmentally sensitive areas in North America.
|Large Mouth Bass||Koi Fish|
Another very common way invasive animals spread is through the pet trade. Often, animals kept as pets will escape or be purposefully released by their owners who no longer want to care for them. These animals will then form wild populations that breed and spread, often uncontrollably. The Japanese koi, a relative of the carp mentioned above, is a domesticated breed of fish that often escapes and forms invasive populations. Some other examples include the Burmese python, the green iguana and the lionfish.
Florida, the home state of Safari Ltd®, has more invasive species than almost anywhere else in the entire world. In addition to pythons, iguanas and lionfish, other animals including the giant African snail, the Monk parakeet, and walking catfish. Unfortunately, these species thrive in Florida’s accommodating climate, and are easily brought into the state by way of Florida’s bustling ports. These animals have devastated the local populations of many animals; it is estimated that there are about 60 species of lizard living in Florida, and only 16 of those are native species. Additionally, Burmese pythons have led to a severe drop in mammal populations in the Florida Everglades, with some species dropping by over 99% in less than ten years. Lionfish are known to eat 70 species of native fish that are of ecological and commercial importance.
|Green Iguana Baby||Green Iguana|
What can be done? Unfortunately, combating invasive species that have established themselves in an area is very difficult. One easy way is to not contribute to the problem in the first place: do not release a pet bird, mammal, reptile, fish, invertebrate, or plant into the wild. Before you take on the responsibility of caring for a living thing, make sure you are prepared for everything that entails. You can also inquire with a local park or wildlife refuge about how to volunteer to help remove invasive species.
Bernie’s Bonus Fun Fact: The tumbleweed, often used to symbolize the Western frontier era of American history, is actually an invasive species originating in Russia. Seeds of the tumbleweed were accidentally brought over with other farmed crops, and the plants thrived so much in the new environment that they came to be forever associated with it.