Reproductive strategies of the golden mussel (Limnoperna fortunei) during the initial invasion in the Brazilian Cerrado

Abstract

The establishment and persistence of invasive species are directly related to their reproductive strategies, which are strongly influenced by environmental factors. The golden mussel Limnoperna fortunei is opportunistic and maintains the same general reproductive pattern during both the invasion and establishment periods. We asked whether this is also the case in the Cerrado biome of Brazil, where the invasion is relatively recent and where the environment may offer ideal physical and chemical parameters for the mussel to spread toward the Northern Hemisphere. Specimens were collected from the mid Paranaíba River and analyzed for condition index, gonadosomatic index, general health condition, and reproductive stage frequency (gametogenesis). Results showed that the golden mussel exhibited a higher frequency of hermaphroditism than might be expected in the early years of invasion. Histologically, mussels were reproductive year-round, with no resting interval, contributing to their high reproductive capacity. Variation in general health condition during the reproductive cycle, combined with histological analysis of the gonads, suggested an optimal period during which the mussel may be more susceptible to control measures. After almost 30 years since the golden mussel invaded South America, there is still no efficient control method; this research may provide a time window to optimize future actions for developing a control strategy.