Maintenance of spatial distribution, density and size structure pattern of freshwater mussel Diplodon Chilenisis Gray, 1828(Bivalvia : Hyriidae) in the Panguipulli Lake, Chile
- The purpose of the present study was to verify eventual changes in spatial distribution, density and size structure in a population of Diplodon chilensis inhabiting sandy and sand-gravel substrates in the Lake Panguipulli after 16 years of studies carried out in the mentioned population. Results indicate that mussels show in 2003 an aggregated spatial distribution in both substrates and a more aggregated distribution in sand - gravel than sandy substrate as in 1987. As in 1987, density was significantly higher in sand - gravel substratum in 2003 (P < 0.01). There were not significantly differences in density within the period elapsed in the same type of substratum. Size structure of population did not show much changes. Nonetheless, young were registered in both substrates in 2003, indicating that recruitment occurred. The results are discussed in relation to the role of these bivalves in the ecosystem and their potential use in ecological evaluation of lacustrine environments.