Density, recruitment and shell growth of the invasive mussel Limnoperna fortunei (Mytilidae) in a subtropical region

CARLOS E. BELZ; GUSTAVO DARRIGRAN; NICOLÁS BONEL; OTTO S. MÄDER NETTO

JOURNAL OF FRESHWATER ECOLOGY

OIKOS PUBL INC

Lugar: Londres; Año: 2010 vol. 25 p. 227 - 233

0270-5060

Limnoperna fortunei (Dunker, 1857) is an invasive freshwater bivalve native to rivers and streams of China and Southeast Asia. In 2001, it was discovered in Itaipú hydroelectric reservoir (South America, Brazil) and its population has grown considerably since then. The aim of this study was to estimate density, recruitment and individual growth of L. fortunei in a subtropical region from a field experiment using an artificial substrate. Samples were collected between December 2004 and December 2005 at Bela Vista biological reservoir in Foz do Iguaçu, Brazil. Mussels were counted and measured to generate size frequency and distribution data. Estimated maximum and minimum densities were 204 ± 17 ind./100cm-2 and 94 ± 22 ind./100cm-2, respectively. Measurements of shell length ranged between 1 to 36 mm and shell-length frequency indicated presence of young mussels with variable densities throughout the period surveyed. The von Bertalanffy model fitted succesfully in all cases explaining more than 96% of the variation in shell length. Growth parameters estimated in this research showed differences to those estimated for populations of L. fortunei in temperate regions (k = 2.35 year-1, Linf = 38 mm).