Bioinvasion Discussion Summary


James Casey


One of the most destructive impacts that humans have on the environment does not directly involve humans. The invasion of non-native species into unprotected ecosystems has hugely destructive consequences. The travel and trade of humans facilitate this bioinvasion. It can occur in many forms. There can be unexpected stowaways in an airplane’s wheels. Shipping containers can be full of organisms hat have no business being where they are. Ships have some of the worst effects on the oceans. Their ballast tanks are havens for every type of sea creature that can be taken aboard. These creatures and picked up at one port with the ballast water and then dropped off at another when the water is released. Some of the greatest offenders are those who trade in organic items. Wood, clothes, food and other natural products can harbor species that could destroy the ecosystem that it is let out in. Most of the time these organisms don’t survive in their new home because the conditions are not right for them. But sometimes they do survive and begin to flourish in their new habitat. At the very least they will begin to take away resources that were once used by other organisms in the area. If there are no natural predators in the region and an abundance of food the results could be much worse. They could go as far as to eradicate entire populations and devastate the local environment and economy. If the local human population is dependent on the plant of animal that has been negatively influenced by the non-native species that was introduced the consequences could be terrible. In this way the bioinvasion of non-native species can have a great negative effect on the ecosystem as well as the human population. Unfortunately efforts to try to stop this have had little success. This is largely due to the fact that people in general do not recognize that it is a problem until it is too late. Alternatively an ecosystem that is ravished by invasive species can look natural and health but really be n dire need of help. An example of the kind of opposition that is being faced can be found with a ship’s ballast water. There are many easy solution to this problem like taking in deep sea water instead of water by the coast, or trying to treat the water before it is released, but all of these ideas take extra time when a ship would be idle and in a world where time is money the people who own the ships do not want to take the kind of time that is needed. The real way to attack the problem is through international trade regulations and monitoring systems but they are very hard to work out. So for the time being we may have to get used to the new organisms in our environment.


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last updated 4/23/06

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