Unity Threads
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The Human Increased Impact of Invasive Species
by: Sylvia Kniss
Native species function within their own ecosystems and have their own roles. When an invasive species is introduced, they interrupt the ecosystems and can cause damage. They may be predators to native species and wipe out that native population. This could cause the whole ecosystem to fall when that piece is no longer in its place. Invasive species are introduced in a variety of ways. A recent example of an invasive species that has reached the news is the Spotted Lantern Fly. This species was found on a shipment of rock exported from China to Pennsylvania in 2014. The lantern fly can cause damage in wooded and residential areas and has become a nuisance for many crops, specifically grapes, while also causing stress to deciduous trees (Cornell CALS, 2022). Non-native species are different from invasive species, however, because they either do not reproduce quick enough, cause harm to native species, or do not adapt well to their new environment. Species can also be introduced with a purpose, such as cats being used as pest control on Marion Island in South Africa, but then have unintended consequences (National Geographic Society, n.d. a). Invasive species are all over the planet and are continuing to spread.
Invasive species quickly take over their environments and threaten the native wildlife of the area. The damage that invasive species cause is contributed to by a variety of factors. Exponential human population growth increases the need for transportation and, therefore, increases the probability that a species will be brought somewhere it should not be. Affluence and unsustainable resource use create avenues for species to be brought in through the demand for live food. People living in poverty do not have the facilities and funding to control and remove invasive species. The cost for species to be introduced does not generally include the factors that do not have a short-term physical use. When people travel, they are isolated from the harm that they are doing to the environment by bringing invasive species with them on their vehicles. The world also has different views about what is important, and many do not believe invasive species are an issue that is serious. Invasive species are an environmental issue that is causing harm all over the world to native species, biodiversity, the food supply, and humans. These effects are only being increased by a variety of human factors, such as population growth, affluence, poverty, full-cost pricing, isolation from nature, and differing world views.
Human population growth has been increasing exponentially for a long time. The result is an increased need for all sorts of resources, such as food, water, transportation, and shelter. As families have more children, they move to bigger houses, sometimes far away from where they lived originally. People move for work or for education, and there is a constant flow of human movement from place to place. As populations continue to grow, more food has to be brought in, creating more opportunities for invasive species to be brought in. According to National Geographic, “invasive species are almost always spread by human activity. The increase of activities such as tourism and trade have meant people and goods can move all over the planet, and they often take invasive species with them” (n.d. b). The spread of invasive species can have huge impacts on the way of life in places like Alaska. For example, if the Norway rat were to be introduced, “more than 100 species of ground-nesting birds used for subsistence in Alaska may be vulnerable” (Alaska Department of Fish and Game, n.d.). As human populations continue to grow, traffic to places like Alaska will increase and so will the possibility of invasive species being introduced. The opportunity for major damage from these species is growing with the human population.
The need for food creates a strong demand and a swift moving trade to meet that demand. In many affluent restaurants, they serve exotic foods, many of which are brought to the United States live. Imports of these animals go through different ports such as the ones in Alaska. The non-native species bring with them disease and pathogens that can cause native species to die while these new species survive and even thrive in Alaska’s waters (Alaska Department of Fish and Game, n.d.). For example, “The snakehead fish and the Chinese mitten crab are two species brought into the U.S. for commercial distribution as food” (Alaska Department of Fish and Game, n.d.). Snakehead fish are aggressive predators, and the mitten crab burrows into riverbanks when it moves upstream to reproduce. This can cause the Pacific salmon to lose habitat to spawn in when those riverbanks erode (Alaska Department of Fish and Game, n.d.). Affluence and the unsustainable use of resources from other countries gives invasive species an opportunity to come into the country and harm native species. These native species may even be a resource for people to use, such as the Pacific salmon, which is a source of food.
People living in poverty generally do not concern themselves with the control of invasive species. They are focused on survival rather than what they can do to prevent the spread of these organisms. In a project in 2016, a group of scientists worked in South Africa to help control the invasive species populations that threatened many species unique to that area. When the new government rose to power, they saw the opportunity to create awareness and support for their goals. In areas that do not have much funding, they “remained concerned about the effects of alien plant invasions on the unique biodiversity of the CFR, because the issue was unlikely to be prioritized by the new government” (van Wilgen and Wannenburgh, 2016). The new government needed to focus on fixed issues such as unemployment and the poverty that many people were living in. This program fortunately created opportunities for employment through their program, but this is not the case in many places (van Wilgen and Wannenburgh, 2016). Invasive species are taking over landscapes, and those areas are too poor to combat it or even care without outside help. This creates an issue of biodiversity loss if action is not taken to prevent the spread of invasive species.
Full-cost pricing is when the cost of both the product and the consequences involved with getting that product are included. For example, when a species is introduced, the cost of bringing that species over does not include the cost of having to remove it once its population gets out of control. Another cost that is not included could be the cost that is for non-use purposes, such as “the value of leaving a natural and functional ecosystem to future generations” or “the value of knowing that a natural ecosystem exists” (Cusack, Harte, Chan, 2009). This can have a huge economic cost. According to Cusack, Harte, and Chan, a “more recent study estimated the costs associated with a much wider group of [invasive species] to be in the region of $143 billion per year. [These] estimates were based on direct-and indirect-use values (such as damage and costs of control) but did not take into account non-use values” (2009). When the full cost of a product is not included, the awareness that people have of invasive species and their impacts decreases. People are not as directly affected so invasive species spread quickly because little attention is directed toward them.
Invasive species also do not get a lot of attention because many people are isolated from thinking about nature in that way. Many people travel without giving a second thought to what might be clinging to their vehicles, which then spread to new areas. Some people are unaware of the issue of invasive species. In a survey conducted on a group of college students in Texas where they were given a quiz on invasive species and it was found that, “The average score on knowledge questions related to invasive and native plants and animals was 32%. Most students underestimated the negative impact of invasive species, but many were aware of costs to manage those species” (Waliczek et. al., 2017). In another survey on a group of nature professionals in Belgium, it was found that “only forty-two percent of respondent horticulture professionals and eighty-two percent of nature reserve managers had a general knowledge of [invasive species]” (Vanderhoeven et. al., 2011). Even people in the field of environmental science are unaware of the full impact that invasive species can have, such as with the food supply or with biodiversity loss. When people are isolated from this issue, they cannot help prevent it, which allows the damage to continue.
There is a wide variety of people and opinions in the world, which allows for a lot of different views on the issue of invasive species. A positive example of this is from the study of Texas college students which found that, “respondents who were knowledgeable of invasive species in the community had more positive attitudes toward the management of invasive species” (Waliczek et. al., 2017). A more negative example from National Geographic is “when government officials encouraged people to plant [kudzu] in an effort to prevent soil erosion. But the kudzu quickly grew out of control” (National Geographic Society, n.d. b). The view that the introduction of invasive species can be beneficial is dangerous when not all consequences are considered, which is the case in this example. Another dangerous view on invasive species is when people do not care about the impact of invasive species, such as when owners released pet Burmese pythons into the Everglades. These snakes preyed on many native species and thrived because they have no natural predators in this area (National Geographic Society, n.d. b). World views not being united in the prevention of the spread of invasive species makes it harder for the issue and the damage to be stopped.
In conclusion, invasive species and the spread of the damage they cause is increased by a variety of human factors. Invasive species can cause damage to the food supply, biodiversity loss, billions of dollars in damage, and loss of habitat for native species. These factors include population growth, affluence, poverty, full-cost pricing, isolation from nature, and differing world views. The damage that invasive species do affects the entire world and its ecosystems. When an invasive species interrupts and takes over a habitat, the effects work their way up the food chain to humans. People should work to raise awareness of the damage humans are causing by introducing invasive species because that damage comes back to affect them in the end. Invasive species are an environmental issue that is causing harm all over the world to both native species and humans, and these effects are only being increased by a variety of human factors such as population growth, affluence, poverty, full-cost pricing, isolation from nature, and differing world views.
Works Cited
Alaska Department of Fish and Game. (n.d.) Invasive species, methods of introduction. Retrieved from https://www.adfg.alaska.gov/index.cfm?adfg=invasive.pathways
Cornell CALS. (2022) Introduction, native range, and current US range. Retrieved from https://nysipm.cornell.edu/environment/invasive-species-exotic-pests/spotted-lanternfly/spotted-lanternfly-ipm/introduction-native-range-and-current-range-us/#:~:text=Spotted%20lanternfly%20(SLF)%2C%20Lycorma,altissima%2C%20or%20Tree%20of%20Heaven.
Cusack, C., Harte M., & Chan, S. (2009) The economics of invasive species. Retrieved from noaa_39804_DS1.pdf
National Geographic Society. (n.d. a) Invasive species. Retrieved from https://education.nationalgeographic.org/resource/invasive-species
National Geographic Society. (n.d. b) People and invasive species. Retrieved from https://education.nationalgeographic.org/resource/people-and-invasive-species
Vanderhoeven et. al. (2011) Perception and understanding of invasive alien species issues by nature conservation and horticulture professionals in Belgium. SpringerLink. Retrieved from https://link.springer.com/article/10.1007/s00267-011-9621-8
van Wilgen, Brian W & Wannenburgh, Andrew. (2016) Co-facilitating invasive species control, water conservation and poverty relief: achievements and challenges in South Africa’s Working for Water programme. Science Direct, 7-17. Retrieved from https://www.sciencedirect.com/science/article/pii/S1877343515000962
Waliczek et. al. (2017) College student knowledge and perceptions of invasive species. American Society for Horticultural Science. Retrieved from https://journals.ashs.org/horttech/view/journals/horttech/27/4/article-p550.xml