We exposed tadpoles to Bd zoospores in water containing one of the three presumed predatory microorganisms. The presence of microorganisms significantly affected the probability of infection . None of the tadpoles exposed with Notommatidae spp. developed infections, 3 of 15 tadpoles were infected in the presence of P. caudatum, and 16 of 60 tadpoles exposed with the Pyrenean P. aurelia were infected.