Significant ecosystem-wide effects of the swiftly spreading invasive freshwater bivalve Limnoperna fortunei

BOLTOVSKOY DEMETRIO; KARATAYEV ALEXANDER; BURLAKOVA LYUBOV; CATALDO DANIEL; KARATAYEV VADIM; SYLVESTER FRANCISCO; MARIÑELARENA ALEJANDRO

HYDROBIOLOGIA

Springer Verlag

Lugar: Alemania; Año: 2009 vol. 36 p. 271 - 285

0018-8158

Since its introduction in South America around 1990, the freshwater Asian mussel Limnoperna fortunei has been shown to strongly interact with several components of the local biota. However, investigation of its ecosystem-wide effectswas hindered by (1) difficulties associated with evaluation of its densities over large spatial scales and (2) scarcity of preinvasion environmental data. The present survey overcomes these shortcomings and addresses the question whether Limnoperna’s impact on the ecosystem-wide scale ismeasurable and significant.On the basis of divercollected bottom samples, we estimated the overall density of this mussel in a reservoir (Embalse de Rý´o Tercero, Argentina), where Limnoperna is present since 1998 and analyzed changes in several water-column properties before and after the invasion. The 47 km2 reservoir hosts around 45 billion mussels; at these densities, a volume equivalent to that of this water body can potentially be filtered by the bivalves every 2– 3 days. Data collected regularly since 1996 indicate that after the invasion water transparency increased, and suspended matter, chlorophyll a, and primary production decreased significantly, with strong changes occurring in the areawith highest mussel densities.Our results indicate that the ecosystem-wide impacts of Limnoperna are generally comparable to those described in Europe and North America for another invasive mussel— Dreissena polymorpha. However, given Limnoperna’s wider tolerance limits, its influence on newly invaded water bodies, potentially including Europe and North America, will probably be stronger.