Alien species dilemma
Non-native species that have been introduced by humans over the past decades have been known to cause a lot of trouble. For example the introduction of rabbits in Australia who were introduced for the hunting sport but quickly caused the most rapid invasion of animals ever recorded(Animal Control Technologies Australia), or the Nile perch that was introduced in lake Victoria and completely disrupted the lakes ecosystem (Ogutu-ohwayo 1990). All for various reasons, whether it is for the hunting or fishing sport, as with the rabbits and some fish species, or to kill a plague in an area, after which the introduced species handled themselves better than expected (Philips & Shine 2006). Internationalisation doesn’t help much either. Almost every kind of species which is farmed or bred can be spread almost all around the world and are being introduced into an area in which it is not native, where escapees or pollen can cause a lot of trouble on both economical and environmental scales. Transport these enables humans to travel to the other side of world while we unknowingly spread all kinds of plant seeds, spores or even eggs from insects for example (Mack & Lonsdale 2001, Keth 1999). All in all humans have become a greater form of global dispersal rather than mother nature itself we have given the non-native or alien species a very bad reputation.
But we should also consider this, it is by all means clear that humans have had a bigger impact on the global ecosystem than all directly or indirectly introduced species combined, mainly by changing the native species’ original habitat in all kinds of ways (Davis 2011). It is therefore not remarkable that non-native species do so well since the original habitat has shifted to a state not suitable anymore for some native species, and because a lot of non-native species are either intentionally or unintentionally introduced, there is bound to be one or more species among them that are able to adapt to the new environment (Davis 2011). Since we might be too late to restore habitats in their original state (and yet we still try to), an article by Mark Davis argues that rather than trying to get rid of non-native species we should embrace them and maybe use them to our benefits. The article mentions for example that tamarisks, which have been introduced from Europe and Asia to America, fulfil in the habitat the same role as the species it outcompeted in the first place.
Non-native species will be introduced everywhere around the world whether we want it or not. Instead of preventing introductions we should maybe do more research in using alien species to our advantage. We changed to world in major way ourselves, so we should just deal with the consequences.
References
Davis, M. A., Chew, M. K., Hobbs, R. J., Lugo, A. E., Ewel, J. J., Vermeij, G. J., Brwon, J. H., Rosenzweig, M. L., Gardener, M. R., Carroll, S. P., Thompson, K., Pickett, S. T. A., Stromberg, J. C., Del Tredici, P., Suding, K. N., Ehrenfeld, J. G., Grime, J. P., Mascaro, J., Briggs J. C. 2011. Don’t judge species on their origins. Nature 474, 153-154, 09 June 2011.
Keth, A.C. 1999. Three Incidents of Human Myiasis by Rodent Cuterebra (Diptera: Cuterebridae) Larvae in a Localized Region of Western Pennsylvania. Journal of Medical Entomology, Volume 36, Issue 6, 1 November 1999.
Mack, R. N., Lonasdale, W. M. 2001. Humans as Global Plant Dispersers: Getting More Than We Bargained For. Bioscience 51 (2): 95-102, 2001)
Ogutu-Ohwayo, R. 1990. The decline of the native fishes of lakes Victoria and Kyoga (East Africa) and the impact of the introduced species, especially the Nile perch, Lates niloticus, and the Nile tilapia, Oreochromis niloticus*. Evironmental Biology of Fishes 27: 81-96, 1990.
Philips, B. L., Shine, R. 2006. An invasive species induces rapid adaptive change in a native predator: cane toads and black snakes in Australia. Proc. R. Soc. B 22 June 2006 vol. 273 no. 1593 1545-1550
http://www.animalcontrol.com.au/rabbit.htm
Interesting topic. I agree that non-native species will be introduced to new areas due to humans, and the question whether it is to the better or worse will always be a hot topic. One ting is how we humans can take advantage from it, but in some ecosystems I actually believe that introduced species can increase the biodiversity and the ecosystems health. Unfortunately, we often know too little of the consequences by introducing a new species to a area, resulting in not doing so (voluntary at least).
Thank you for your article about invasive species. I think you are right, when you say that it is a mistake to see only the downside of introduced species and that their over all bad reputation is made by human. There have always been alien species introduced and this don’t need to be a bad thing. But I really think, that in the cases in which humans introduce species on purpose, we should definitely do proper research before and think twice, if or if not this is the best solution.
I think the main problem is that often the effects of invasive species are only realised too late when the damage could potentially have become irreversible. We can benefit from invasive species but then we need to decide how we value the origianal biodiversity landscapes more than the benefits.