Saturday, May 15, 2010

Invasive issues and complicated species

 I apologise to my readers for the lack of hyperlinks.  However due to an IE8 upgrade I did not want, I am no longer able to write in word and copy to blogger with my hyperlinks intact.  If anyone has a non technical, non download necessary, easy to handle solution, I am all ears.   Until such time as this Technosaur, or IE and Blogger figure things out, I suppose that I will be reduced to just writing the words with out the new fangled technologies.



The issues that make up the world of invasive species involve a large number of stakeholders and interested parties. These parties are usually only interested the continuum of invasion that directly impacts their interests. Medical health professional for example are very interested in insects that can transmit human disease such as the tiger mosquito and West Nile Virus. Gardeners are interested in invasive insects and diseases such as Japanese beetles, Popillia japonica, first found in New Jersey around 1916, which attack many ornamentals including hybrid tea roses and the dogwood destroying fungus, anthracnose, Discula destructive, first seen in the United States near Connecticut and Washington State in the mid-1970s. Farmers are concerned about invasive weeds such as cogon grass, Imperata cylindrica, and soybean rust, Phakopsora pachyrhizi, to name only two of the many non indigenous species that can decimate agricultural yields. The recreational fisherman struggles with the non native Hydrilla verticillata while the commercial oystermen fight against the newly introduced green crab, Carcinus maenas.


Some species are invasive per se, such as emerald ash borer, kudzu, Asian long horned beetle or lythrum in specific conditions that allow their rapid expansion and domination. Invasive species can travel on their own power once introduced. Or, they can make use of one of the most efficient vectors or transport organisim which, of course, is mankind. They make use of the pathways created through his travel and his fast moving and wide-ranging marketplaces. Repeated reintroduction places pressure on the native self sustaining ecosystem until a point is reached at which the invasive species caused stress becomes so great that the original ecosystem begins to dramatically alter or even fail. One invasive species like the proverbial pet rabbit is usually not a problem until the next day when there mysteriously is suddenly and more than one rabbit about which to care.


Invasive species can attack humans directly causing illness, injury and death. Further, they can attack the ecosystems humans depend on thereby also causing illness, injury or death. Our solutions to the two events are interestingly dissimilar if not unexpected. We tend to get very excited about the first kind, and perform an elaborate denial maneuver akin to an ostrich when thinking about the second type of invasion. That is not to say that a 15 foot python or 60 pound flying carp cannot directly focus one’s immediate attention. However the focus is short-lived in ecological terms. The immediate attention is on the individual invasive species as a misplaced species in the sudden excitement of the moment rather than the head hurting, complications found by considering the invasion process and implications for tomorrow.


Invasive species coast resources calculated by some to be around 130 billion dollars per year/ This calculation does not include the loss of what might have been. For example, how are we going to calculate the loss of ash trees for baseball bats when there are no ash trees? What is the value of the loss of the Sonoran Desert landscape when the African buffel grass completely takes over in the American southwest? How do we calculate the value of not being able to eat an oyster, or to scuba dive safely because of lionfish invasion of Atlantic waters? If there are no more eastern woodland native wild flowers because of the non indigenous invasion of weeds and escaped ornamentals, what is the cost in dollars? More importantly, does anyone care enough to pay to stop the invasion? Is there anyone willing to make a sacrifice to preserve that upon which we cannot place an exact present dollar value?




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