Landscape Ecology, biological invasions, pérdida de biodiversidad, invasiones biológicas, Lithobates catesbeianus, Lithobates pipiens, ecología del paisaje, enfermedad emergente, emerging disease, bullfrog, biodiversity loss, dulceacuícola, leopard frog, freshwater conservation, Rana pipiens - microbiology, Rana catesbeiana - microbiology