Freshwater sponges overgrow the invasive golden mussel Limnoperna fortunei in the Upper Parana River, Brazil

The golden mussel Limnoperna fortunei is one of the top three invasive animals in Brazil. It is widely distributed in South America, changing the whole environment, and causing exorbitant expenses for hydroelectric power plants (HPPs). The aim of this report is to record freshwater sponges as a natural enemy of the invasive mussel in the Upper Parana River. Specimens of six native sponge species were observed overgrowing the L. fortunei in SCUBA dives conducted in three HPP reservoirs. This type of competitive relationship is poorly understood in South America, but it is similar to previous reports of freshwater sponges around the world interacting with other invasive mussels, such as zebra and quagga mussels. Further studies must explore defence mechanisms of both groups using in situ and laboratory-controlled experiments and identify metabolites expressed to understand the dynamics of the ecological interaction.

Automated summary

The aim of this report is to document freshwater sponges as natural enemies of the invasive golden mussel in the Upper Parana River in Brazil. These sponges overgrow the golden mussel and the competitive relationship observed is similar to previous reports of freshwater sponges interacting with other invasive mussels around the world.