Abstract

Obtaining settlement of laboratory-produced larvae on the surfaces of plastic net-bag collectors is a critical step in the production of "seed" scallops for mass cultures in the sea and is a commonly process used in Chile. The results, however are variable and irregular. The present study evaluated the possibility of biologically pre-treating net-bag spat collectors using bacterial strains, in order to facilitate the settlement and metamorphosis of the scallop larvae. Three bacterial strains were isolated from the microflora attached to collectors with high percentages of larval settlement. The collectors were exposed in simple form and combined with the bacteria selected to compared a) the settlement in the treatments with bacteria and b) normal conditions of culture. A second group of collectors was concurrently tested by the same method, with the addition of peptone and yeast extract to increase the development of the bacterial primary films. The results suggested an increment of scallop settlement in bacteria-treated collector bags which were treated with nutrients. The results obtained after 30 days of culture in the sea were higher when the three strains were combined (243,45%). The results suggest that the employment of strain periphytic in the settlement phase is a feasible way to improve the settlement of scallop larvae.