摘要:AbstractThe invasion of exotic species in aquatic environments is one of the several factors responsible for altering the dynamics of fish communities. The golden mussel Limnoperna fortunei was first recorded in the upper Uruguay river, Brazil in 2012 and since then there is an open need to discuss and evaluate how this invasive species interferes with the life of the ten must abundant fishes of this region. In order to achieve this, this work uses two different nonlinear state-space models to describe the dynamics of the K condition factor and abundance of these communities, whose parameters are identified by extended Least Squares procedures, considering real, in locus collected data. One model is polynomially nonlinear on the states and the other is linear, while both are output-nonlinear. This work also evaluates quantitatively how the (sudden) presence of the golden mussel medelled with the aquatic life of the upper Uruguay river, with the aid of high-fidelity simulation results. The methodology points to significant changes in five distinct fish communities, which was also partially observed in nature. Moreover, preliminary results regarding control techniques are also presented to illustrate how environmental policies could act to prevent a biological catastrophe due to this invasor.