Marris Chapters 6-7

The negative perspective towards invasive species is fueled by emphasis on such “new germs and viruses [that] can make people and animals sick” or the “introduced species [that] can cost farmers and ranchers big money, as they destroy crops or displace more palatable species on the range” (Marris 99). By focusing on such cases as the introduced brown tree snakes species that “has killed off ten of twelve native forest-dwelling birds on the island of Guam,” (99) we are only considering the negative aspect of introducing new species to a region. When it comes to invasive species, similarly to other topics Marris addresses in her book, we could perhaps benefit from being more open minded with the ability to recognize the possible beneficial impact a species could have on the new ecosystem it is being introduced to. One example that illustrates the potential benefit of new species is that in Britain, where climate change caused chicks to hatch early, leaving them without caterpillars to eat. In this case, the newly introduced European Turkey Oaks were beneficial to the survival of the chicks as they brought with them wasps that served as food in lieu of the caterpillars. Examples like these are necessary as they illustrate the recurrent benefits that many so called “invasive species” can have on ecosystems. Marris brings up a valid point by questioning why we are inclined towards disliking the introduction of new species. I agree with the notion that perhaps it is because we “merely fear and dislike any change” (107). I also agree “the invasive species paradigm is so easy” and that it is simply convenient for us to implicitly immediately judge new species as invasive and dangerous and solely welcome natives in ecosystems (108). Ecologist Mark Davis brings up another valid idea, suggesting we should “forget about where they came from, identify species that are causing us problems…and then deal with them” and perhaps we could deal with each species as a “separate case” rather than categorizing based on native or invasive status (108).   I appreciate Marris’ introduction of novel ecosystems, as they appear to be a good balance between complete conservation and radical moves such as assisted migration. Novel ecosystems are “defined by anthropogenic change but are not under active human management” (114).  I am optimistic regarding the concept of introducing a species to an environment and allowing it to thrive, perhaps even assisting the processes of evolution and natural selection. My optimistic outlook towards the idea of introducing new species to an ecosystem stems from the positive results from scientists such as Ariel Lugo who “found that the novel forests [in his study], on average, had just as many species as native forests” (119).  Although I, like Mascaro states, recognize that ”we will always have to deal with the risk [new species] pose to other systems,” I think we should further work towards and research novel ecosystems as it would be unfair to simply dismiss their potentially beneficial role in our environment.