The golden mussel: understand why this invading species is dangerous to nature

Foto: CBEIH/Divulgação

Have you ever heard of the golden mussel? It is a small freshwater mollusk (three to four centimeters long) originating from Southeast Asia that arrived in Brazil by the waters used as ballast in cargo ships. Due to its ease of attachment to rigid structures and great proliferation capacity, the golden mussel stands out as an invasive species due to its potential to cause obstruction of pipelines and equipment in hydroelectric power plants and supply facilities, in addition to affecting the natural habitat of fish and aquatic animals.

The Golden Mussel is considered an invasive species, i.e. it is not natural to the environment, and can be harmful, altering its characteristics and the natural balance of other communities. In Brazilian waters it has reproduced uncontrollably, for not having a predator and finding a favorable environment for its adaptation.

Industries, crops, hydroelectric plants among other segments, which use raw water (which comes directly from rivers) are constantly having to perform inspections and cleaning of their pipes. In the form of larvae, the mussels enter the pipes and settle there until the adult phase, obstructing them and forcing constant cleaning. The places where mussels are settled are transmission cooling pumps (from water collection stations), pipes of heat exchangers of hydroelectric power plants, irrigation systems among others.

In Brazilian rivers, the Golden Mussel – which comes from transoceanic ships – consumes a large part of the food of native mussels – contributing to their extinction. It also contributes to the death of fish that cannot digest them and also of animals such as lobsters and other mollusks, since the mussels stick to their surfaces and prevent them from moving, defending and even feeding themselves.

How did the Golden Mussel get to Brazilian rivers?

The Golden Mussel larvae or adult individuals arrived in the port of Buenos Aires, Argentina, around 1991, brought by ballast water of transoceanic ships. In only 10 years, they managed to spread through almost the entire La Plata basin, reaching the Paraná River with densities that can exceed 120,000 individuals/m².

What is ballast water?

It is the one that remains in vessel tanks. When they travel empty, their tanks are filled with water to help maintain stability and as soon as the load is placed the water is released. Each tank can have millions of liters of water and in it there can be anything from bacteria, algae, worms to even fish.

Cemig and the Center for Bioengineering of Invasive Species of Hydroelectric Power Plants (Cbeih) began their research to develop products based on calcium carbonate, an element commonly found in Golden Mussel shells. Some of them are: lime-based paints, fertilizers, poultry food.

What you can do to lessen the impacts of the Golden Mussel:

If you use boats, speedboats and other vessels for fishing and leisure, you can help to reduce the spread of the Golden Mussel and the environmental impacts caused by it. When moving from an area where the mussel is present to another, disinfect your vessel with commercial bleach or chlorine, according to the guidelines below:

Empty any water reservoir on the boat ashore;

Remove any vegetation residue found inside and outside the boat or trailer;

Clean the possible incrustations of adults with waste disposal on land;

Wash the entire boat, especially the hull, bait ponds and the trailer;

Throw bleach where water accumulates, especially in live bait boxes;

The entire boat must be brushed with a soft broom dipped in bleach.