The golden mussel, Limnoperna fortunei, is a medium-sized freshwater bivalve mollusk belonging to the family of true mussels. Generally, they only grow to between 0.79 and 1.18 inches in size and have a golden brown shell. Sometime, between 1965 and 1990, the mussels spread to Hong Kong, then Taiwan and Japan.
Around 1990, this invader was discovered in an estuary of the La Plata River in Argentina, brought into the country in the bilge water of Chinese freighters. Today, almost 20 years later, the invader is found in five South American countries and is widespread in the La Plata, Uruguay and Paraguay river basins, as well as the Tietê River and the Patos Lagoon system.
While this highly aggressive invasive species has taken over a wide range of river ecosystems, researchers fear it is only a matter of time before they reach the Amazon River, the largest and most important river in South America. The Amazon is a hydrological engine, playing an important role in both regional and global climate conditions.
The world’s smallest hydrological engineer
The golden mussel has been dubbed an “ecosystem engineer,” meaning it can alter dramatically the sediment in lake beds and create changes in the associated invertebrate communities. They can also clog pipes, disrupt dams and create malfunctions in other hydraulic machinery. Because they are filter feeders, they end up increasing the concentrations of phosphorus and nitrogen in the water, causing toxic algae blooms that can kill off native aquatic animals.
In a study done in 2010, the golden mussel was compared to the zebra mussel, another invasive species that entered Lake Erie, as well as many other countries. What the researchers found is interesting. Golden mussels are far more tolerant of increased salinity, lower pH levels, and higher temperatures than zebra mussels. North America was also taken into account in this study, the scientists saying the golden mussel would be able to find a niche in places not suitable to the zebra mussel. The same holds true in South America, and, in particular, the Amazon River and its tributaries. These invaders would devastate the native freshwater mussels.
As with the zebra mussels, golden mussels have also helped to increase fish populations. But this phenomenon is a “two-sided sword.” Computational biologist Marcela Uliano da Silva, a native of Brazil who’s trying to thwart the mussels’ proliferation, told the TED Blog, “But when you increase the number of fish, it has a domino effect, as they are at the top of the food chain. Ultimately, when the mussel invades, it transforms the ecosystem, decreasing biodiversity and homogenizing the environment.”
Da Silva is working on creating a that targets a specific genome in the golden mussel. She says it could be released, infect the mussels and make them infertile. But other scientists are a bit nervous about this plan, saying it may even be dangerous, saying the “bio bullet” could possibly do more harm than good when it’s released. “Every day, I’m anxious,” Da Silva admits. “But you have to be able to live in agony. Otherwise, you’re not going to do great things. … You cannot be safe. You need to take risks.”
