Comparison between IMTA and monoculture farming of mussels (Mytilus galloprovincialis L.) in the boka kotorska bay

Abstract

This paper presents the resuls of growth rate and condition index analysis of Mytilus galloprovincialis in integrated system and monoculture. The aim of this study was to show if there are differences in growth and condition index of mussels between integrated multi-trophic aquaculture (IMTA) and monoculture farming. The growth rate and condition index were monitored during a 13-month study at three different sites: 1) close to fish cages (NBL), 2) 100 m removed from fish cages (NUD), 3) at a monoculture mussel farm (SVN) around 8 km far away from cages. The most intense growth of mussels was recorded in spring, and the least intense in summer. After 13 months, monitored individuals at all three locations achieved commercial size. The growth rate was very similar at all sites. The condition index showed spatial and temporal differences. Condition index values on site NUD were mostly higher compared to SVN and NBL, which were very similar, exept for the period from October to December when CI was similar on NBL and NUD site and higher in comparation with SVN. CI values on NBL an NUD site during cold period indicate on fact that mussels probably feed on the nutrients from fish farm origins.The highest mortality rate was recorded at the NBL site, probably due to the effects of fouling organisms.