Questioning Invasives by Raichle Dunkeld
When invasive species take hold of an environment and assert themselves as the dominating force, they often obliterate the landscapes they’ve infiltrated. This is due to the fact that dominance over new, resource-rich environments gives invasives an acute ability to propagate in high volumes. Native species populations, namely those in direct habitat competition with invaders, are the first to drop and invariably a monoculture is established. Think of the rainbow trout, Oncorhynchus mykiss, introduced throughout the United States by government programs bolstering “American manhood.” This species has effectively been introduced and re-introduced by American National Park systems, and where rainbows were introduced, they took hold. Unfortunately, instead of adding to native environments, the rainbow trout caused widespread species loss. Among the casualties was the decimation of populations such as the Golden Trout of California, a native to precious few alpine regions and known for its scales’ glimmering response to sunlight (Halverson, 2011).
Not unlike our dedication to “add” to natural landscapes through non-native species introductions, humans as onlookers and members of localized environmental communities often feel the need to step in, to “save” natives threatened by a takeover. Beyond our demonstrated ineffectiveness in managing ecosystems, there is a profound irony that lies in our control of invasive populations, because as a dominant species in our own habitats, it isn’t far fetched to look at the human population as an invasive species. We have spread far and wide, inhabiting landscapes that we didn’t evolve in; we aren’t meant to live in Polar Regions, but through ingenuity we have adapted to harsh climates such as the Nordic States. So far, we have played a major role in the current mass extinction, earning ourselves the naming of a new geologic era, the Anthropocene. As a general rule, where humans go, biodiversity falls as native landscapes are defaced. Human effect on ecosystems, in comparison with other species, is magnified to such a degree that our impact is worthy of a global recognition—a title for our era, the age of humans, the Anthropocene. The extinction of charismatic megafauna has been especially pernicious over time, with species such as the Sumatran Rhino on its last leg of existence. The last of its fertile individuals (one male and one female) are being cared for at the San Diego Zoo. After years of failed inseminations, researchers are considering relinquishing their hold on the species and conceding to the extinction of the Sumatran Rhino (Kolbert, 2014).
We treat invasives as poison to an environment, with little to no benefit to the spaces they inhabit. National park systems utilize all resources available to eradicate invasive species when present, and this fight isn’t just national. Organizations in the Galapagos Islands spent decades on the eradication of invasive galapa-goats, and researchers in Australia have spent hundreds of thousands of dollars on management of invasive cane toads, a species introduced in the 1960s (). In the US alone, we spend $100 million every year on invasive species prevention (US Fish and Wildlife, 2012). We see invasives as incredibly detrimental to environments, and are willing to pay through the nose to eradicate them. With such a negative stance on invasive species and an acute awareness of our own interactions with the environment, as an unbiased observer looking in on the state of our world, should humans be eradicated for the sake of all other species on the planet?
References:
Halverson, A. (2011). An Entirely Synthetic Fish: How Rainbow Trout Beguiled America and Overran the World. New Haven, CT: Yale University Press.
Kolbert, E. (2014). The Sixth Extinction: An Unnatural History. New York, NY: Henry Holt and Company.
US Fish and Wildlife. The Cost of Invasive Species. 1, 2012. http://www.fws.gov/verobeach/PythonPDF/CostofInvasivesFactSheet.pdf (accessed 30 5, 2015).
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