Reading the four articles, especially the Mute Swans article, got me thinking about the definition of invasive species. While the ecological definition of invasive species is relatively well defined (“non-native species of plants or animals that out-compete native species in a specific habitat” from http://www.floridasprings.org/glossary.html), I feel that that the qualities that label a species as “invasive” and offensive by the public are much more vague.
The Mute Swans, for example, are scientifically an invasive species. The species was first introduced to the East Coast from Europe and Asia in the early 1900’s, when they were imported as decorative birds for parks and estates. Wild Mute Swan populations increased drastically in the Chesapeake Bay in the 1980’s and 90’s, as they out-competed native species for food and habitat. Legislation was passed in 2000 to control the swan population. There has, however, been public opposition to killing the mute swans. The article from class mentioned the “deeply divided” state panel, and the opposition from animal rights groups.
Mute swans pose just as great a threat to native species as snakeheads or didymo, but the opposition to swan population control in the Chesapeake made me wonder why there were no similar movements for these species. I guess the fact that swans are more aesthetically pleasing (as opposed to http://www.mountainmurmur.com/wp-content/uploads/2008/11/didymo-mararoa_s1.jpg) does influence public opinion on how comparatively “invasive” species seem, since noone wants didymo in their water. I’m sure there are many other invasive species that drastically disrupt native ecosystems and completely drive away certain species, but we don’t make a big deal about them because we are okay with having the invasive species around. There are factors (economic or aesthetic) other than endangering native ecosystems that the public takes into account when we decide whether a species is “invasive” and should be eliminated, or if nature should be allowed to run its course.