Saturday, June 26, 2010

Invasive species and oil spills impact ecosystems similarly

          What is so upsetting about the spread of oil across the ware and shores of the Caribbean? Is it the pictures of animals coated with oil slowly dying? Or recreational shorelines no longer open for human use? Perhaps it is the loss of jobs that once supplied our menus? Could it be the change in economics to an already stressed economy, or perhaps the loss of ecosystems that support our ways of life? Are we afraid of what tomorrow has in store with the dramatic change from what we new to the novel species limited environment that is in store? The oil freely gushing is the same oil for which we pay dearly in order to drive to restaurants and fly to beaches, to heat and cool our homes and to make the pharmaceuticals and plastics that fill our world.
          There is another carbon based spill that is invading our ecosystems and altering our ways of life. Unlike oil, which come from the remains of plants and animals, this wave of change is alive. It comes silently in the packing of the goods we import from near and far; it comes with us as we set sail in our boats; it follows us in to the water when we fish in felt bottom boots; it flows over the garden fence from purchases of beautiful flowers whose danger we do not notice. Invasive species bring disease and they bring death. They alter local ecosystems as surely as the charismatic oil flowing in the Gulf of Mexico, and they cost us the use of the environment. Invasive species limit our food supply and create medical problems. Invasive species change the temperature of wild fires and can impact the soil creating conditions for mudslides. Invasive species overwhelm the native species of today beginning a cascade that can lead to species extinction. And like oil they can provide energy, food, flowers, fiber, and feed, thereby providing opportunity for business and jobs.
          The oil is a catastrophic environmental disturbance that is changing much of the ecology of the gulf in ways we do not understand; invasive species are changing the world in a similar fashion. Invasive species are a biological wildfire, an oil spill with global reach that is silently changing our ecosystems because of our outputs and without our input. Invasive species come in with our purchases either directly because we choose to buy them or indirectly because we do not know they are there. Oil, free flowing from a well, looks like, smells like and acts like oil. There is no problem in knowing what you are seeing and what is causing the environment to change before your eyes. Invasive species on the other hand can be microscopic and hard to see or large enough to bite and yet remain  hidden behind a kitten's purr. From a virus or bacterium invading a forest or a field to a rat in an alley or a feral pet in the park, invasive species are hard to see and harder yet to define. The damage caused by these invaders disturbs the complex web of interactions pushing ecosystems to the tipping point..
          We like our oil in controlled situations, in tanks of cars and in plastic form. And so we like our invasive species; our little pet pythons in cages at home and our gentle English ivy container bound. We love the cool of oil in the heat of summer time and we love the quick shade of the Norway maple for a summer's eventide respite. And in so loving we quietly enjoy the short term benefits without knowing the long term impacts. Any negative outcomes to oil that moves without control or to invasive species that spread without concern is chalked up as necessary externalities which are a result of just the way things are and always have been. The assumption is that nature, which we feel individually as overwhelming in her force, is large enough to dispose of all that we cannot control or do not want.
          The collapse of a complex system such as a society dependent on a natural resource or ecosystem services is an opportunity to restart that comes at great cost. However, the collapse of existing ecosystems is happening without most of us aware; for the changes that come from invasive species come like the biblical thief in the night and shall wake us to a new and novel world not of our memory. We are sleep walking into history shepherded by invasive species and our need for oil. Thinking about invasive species and ecological change is very upsetting for it tells us things we do not want to know.

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