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The golden mussel (Limnoperna fortunei) has caused worldwide problems for the eco-environment and man-made structures. There have been many control strategies proposed, which have various strengths and weaknesses. To help selection of the effective control strategies that consider the biological traits of L. fortunei and the actual situation of biofouling, we studied the ecological amplitudes that indicate the tolerance of the species to environmental conditions and propose appropriate strategies based on their ecological amplitudes. We set five levels for the environmental factors water temperature, dissolved oxygen concentration, pH and ammonium ion concentration and four levels for light intensity. The survival ratio and attachment ratio of golden mussels under the different environmental conditions were measured and the nonlinear regression models were used to simulate the ecological amplitudes of golden mussel. The results show that their ecological amplitudes are wide-ranging with respect to water temperature (13–29 °C), dissolved oxygen (> 1.5 mg/L), pH (4.1–8.7), ammonium ions concentration (lower 65 mg/L) and light intensity (0–55,000 l x) and the mussels show obvious negative phototaxis. Therefore, adjustment of the environment with high water temperatures, low dissolved oxygen, high pH values or strong and continuous light illumination is suggested as a potentially effective control strategy of golden mussel biofouling.

The golden mussel, Limnoperna fortunei, is native to South China but has spread to Japanese freshwater environments as a nuisance invasive species. The golden mussel colonizes hard manmade substrates and its attachment can cause economic losses at water intake facilities. To evaluate the repellent effects of the high alkalinity (pH 12–13) of freshly prepared cement mortar on golden mussels, test pieces made of cement were immersed in a Japanese urban tidal river. Compared with coated mortar, and wood and limestone test pieces, the cement mortar did not show significant repellent effects on golden mussel attachment. Therefore, concrete constructions on riverbanks may be a preferred substrate for golden mussel colonization. A 4-year immersion experiment showed that copper substrate had a strong repellent effect on biofouling, while cement mortar, aluminum, and stainless steel did not have any adverse effects on golden mussel attachment. This experiment also revealed the settlement of invasive golden mussel in an urban tidal area where the salinity fluctuated up to 20.0‰.

The invasive bivalve Limnoperna fortunei (Dunker 1857) was introduced in South America in 1991, with the first occurrence in Brazil in 1998. In the Iguassu River, the species was recorded in 2001; however, it is unknown how it was introduced and spread. Adults and larvae were sampled in Iguassu and Parana Rivers, and the genetic profiles were compared. The species was absent in the upper reaches and only larvae were found, in low densities, in intermediary reaches. The L. fortunei populations from the lower Iguassu River presented no genetic differentiation among themselves, suggesting strong connectivity, and were significantly different from the Parana River populations, most likely because of Iguassu Falls. Furthermore, the results suggest that the Parana River represents the source of propagules to the Iguassu River. Generally, no significant differences were observed between the genetic structure inferred from adults and larvae. Only the population from the Iguassu National Park, a lotic environment, differed from the remaining subpopulations. The characterization of genetic profile using larval stages of L. fortunei populations was satisfactory, and represents an important protocol for studying the population genetics of aquatic species with planktonic larval stages.

We investigated the predation and depth effects on abundance and size distribution of an invasive freshwater bivalve, Limnoperna fortunei, post-larvae using screened (5-, 25-, and 50-mm mesh openings) and unscreened cages at three depths (6, 12, and 1 m above the bottom) in a dam reservoir, Lake Ohshio of Japan. The densities of L. fortunei on the unscreened cages were much lower than those of the 5-mm mesh screened cages at any depth. The predation rates estimated by dividing the density of the unscreened cage by that of the 5-mm mesh screened cage were 97.3% at 6 m depth, 96.6% at 12 m depth, and 95.8% at the bottom. Shell lengths of L. fortunei post-larvae were small on bottom cages, and their size distribution was significantly different from those at other depths. These results suggest that predation and depth affected the abundance and size distribution of L. fortunei in the lentic environment. The impact of L. fortunei invasion on the food web and the possibility of regulating their population by predation pressures are also discussed.