Efectos del desdoble sobre la biomasa cosechable de Mytilus platensis D'Orb en cultivo.
MetadataShow full item record
The effect of thinning on the harvestable biomass of mussel Mytilus platensis (d'Orb.) cultures was analyzed. Mussels were grown on ropes in sub-surface long-lines in Golfo Nuevo (Chubut, Argentina, 64° 59' W; 42°46' S) during a 15 month period (January 1987-April 1988). Ropes were seeded using the Spanish method with 2,000 individuals per rope meter. The thinning-out was performed three months later using the following thinning ratios (TR: number of half-grown ropes obtained from one seed rope):1,6 (900 individuals m super(-1)), 2,4 (600 individuals m super(-1)) and 3,2 (450 individuals m super(-1)). Growth rate (shell length and meat weight), survival and number of harvestable ropes increase with the thinning rate; the harvestable biomass being larger at the highest TR. The largest harvestable biomass is reached at the 12th month of culture, decreasing at the 15th month. The differences between the harvestable biomass at the 12th and 15th months are lower at TR: 3,2. For that reason, if mussels are to be maintained on the ropes beyond the optimal production time, it is convenient to use the highest TR. The main effect of thinning on harvest is due to the increase in the number of ropes obtained from the initial rope.