Exotic species have been labeled as “invasive” since most of them excel in their new environments, eventually displacing native species or disrupting the ecosystem. Chapters 6 and 7 of the Rambunctious Garden discarded the popular view of exotic species and revealed alternate research on the other, lesser known, effects of exotic species. Most traditional ecologists view exotic species as a danger to most ecosystems in the world. This is because existing exotic species around the world have shown devastating effects such as economic damage or altering native species populations (by hunting them or simply over population). These invasive species are either nuisances to humans or they cause problems in ecosystems around the world, potentially causing the extinction of several species as they invade.
Emma Marris provides insight on why exotic species may not be as dangerous as they seem and why removal of these species would waste money. The disadvantages of exotic species are highlighted in the media, which makes the tamer and more useful exotic species ignored. The uses of exotic species falls in line with many modern conservation ideas like rewilding or assisted migration. Many species can be used to fill in niche roles in ecosystems and some of them have little impact on ecosystems in general. The main objection of many ecologists to exotic species is mostly due to their non-nativeness.
Another concept that is touched upon is the novel ecosystem, or a dramatically altered ecosystem, and how exotic species in the ecosystem have evolved the ecosystems and made them stronger. These exotic species tend to be invasive at first, and the, despite what many ecologists want to believe, the other species manage to adapt and control the invasive specie, like how native ducks learned to eat Zebra mussels in Lake Erie. Marris writes in her chapter how man of these novel ecosystems are more “vital and energetic”. These ecosystems are not controlled by humans which allow natural selection to take over, resulting in a healthier ecosystem; research has shown that ecosystem services like water filtering or erosion control are better in these novel ecosystems.
Humans have to admit that these novel ecosystems and exotic species are a result of human interaction, and similar to what Marris says, these novel ecosystems have already evolved and adapted to the exotic species and human interaction, thus trying to restore the native species is the same as going against nature/natural selection. I like the idea of letting natural selection run its course (unless the exotic species are really toxic) and develop more complex ecosystems that are adapted to the growing human influence on the world. This idea seems to focus more on letting nature be rambunctious, but there should be some human intervention or control if the ecosystem is endangered. My main objection to these chapters is how little importance is given to the native species that are endangered, and how they are portrayed as a necessary casualty of novel ecosystems.
