Aquatic Invasive Species

Fifty years ago, Miconia Calvescens was only known to make its home from Mexico in the north, down to Brazil and Argentina in the south. Today, that range includes not only the original land, but several pacific island groups, thousands of miles away. In Tahiti, nearly two thirds of the existing rainforests is composed of this “green Ebola”, whereas only a relatively short time ago, it was unknown on the islands (Meyer and Florence 1996). Closer to home, on the islands of Hawaii, Miconia has also made a significant impact, and although it does not constitute as large of threat as it does in Tahiti, Hawaii is on the verge of the same ecological disaster.

The first step to understanding the threat Miconia poses on the Hawaiian islands is to look at the idea of island ecosystems. The idea is that a body of land that has been separate from the mainland for long periods of time will slowly develop unique life forms not found anywhere else in the world. This is certainly the case with Hawaii. Species such as the crested honeycreeper, the nene (a type of goose), hapu’u fern, and the ‘ahinahina (a.k.a silversword) are found only on this small island chain in the northern pacific ocean. It is species like these, and the ecosystems that they inhabit, that are most threatened by the invasion of Miconia on the islands.
The National Geographic film, “Strange Days on Planet Earth,” follows researcher Dave Duffy as he attempts to explain the Miconia’s success and develop effective methods to prevent it from becoming more widespread. The first part comes much more easily than the second. Duffy, and other researchers, have found that because of the broad leaves of miconia, the plant can easily beat out many of the native species for sunlight. This, coupled with the fact that it produces a large amount of seeds, gives this species a significant advantage over the natives. The second half of the goal, however, is much more elusive. According to the film, there is no fail-safe solution for Miconia in the Hawaiian islands. Instead, activists and researchers are forced to remove the plant mostly by hand. Although several methods have been established for locating areas of high Miconia density, these only offer a helping hand and do not directly effect the number of Miconia plants on the islands.

The approached featured in the Miconia segment of “Strange Days on Planet Earth” is far from the most desirable path. Destroying patches of Miconia by hand only acts as a way to put off an inevitable expansion of Miconia throughout the forests of the Hawaiian Islands. Even with the large amount of people who do contribute to the effort, this plant remains so widespread and located in many difficult-to-reach areas of the islands, that nearly nothing short of total extermination will end the problem. With this said, however, there currently does not exist a better solution. At the very least, this approach is preventing the further spread to this “green ebola” and ultimately helps keep a lot of the native ecosystems still intact. Still, until a final solution is found, Miconia will remain a huge threat to the Hawaiian islands.

Meyer, Jean-Yves, and Jaques Florence. “Tahiti’s Native Flora Endangered by the Invasion of Miconia Calvescens.” Journal of Biogeography 23.6 (1996): 775-81. Wiley Online Library. 1 May 2007. Web. 23 Jan. 2011. <http://onlinelibrary.wiley.com/doi/10.1111/j.1365- 2699.1996.tb00038.x/abstract>.

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