[A preliminary study of variation in Tarebia granifera (Lamarck), Río Hatibonico, Camagüey].

A study was carried out on Tarebia granifera in Camagüey which allowed to gather ecological evidence in order to know this freshwater mollusk species likely to act as a biological control agent of intermediate hosts for tropical diseases. Highest density was observed in November, coinciding with the highest temperatures of a running water habitat. Also, there was an influence of density variations according to variations of ions NH4+, NO2- and NO3- concentrations in the medium. These data are useful to know the right time for extracting Tarebia granifera from the habitat and using it as competitor without considerable alterations in the population stability.