The mass decline of amphibian populations poses a serious threat to global biodiversity and ecosystem health and stability. The pathogenic fungus Batrachochytrium dendrobatidis (Bd) has contributed to the extirpation and extinction of hundreds of species worldwide. Bd produces potentially damaging metabolites during the host infection process that may affect host growth and development, even in the absence of actual infection. Here, we exposed crayfish (Procambarus) and Cuban tree frog (Osteopilus septentrionalis) tadpoles and adults to one of three treatments (live Bd, Bd metabolites, or artificial spring water) and tracked development, growth and survival for one month.
Results/Conclusions
Metabolites increased crayfish gill tissue recession, which decreased crayfish respiration (X21 = 5.26; p = 0.021). Tadpoles exposed to Bd metabolites alone developed faster than those exposed to live Bd or ASW (p < 0.001). However, there was no difference in mortality, tadpole length or weight change among treatments (χ 21 = 5.05, p = 0.08, χ 21 = 1.28, p = 0.53 and χ 21 = 1.67, p = 0.44, respectively). There was no effect of treatment on adult growth or mortality (χ12 = 0.11, p = 0.74, χ12 = 0.05, p = 0.83, respectively). These results indicate that while hosts do not always appear to be notably impacted by non-infectious exposure to Bd contaminated water, these metabolites may be causing significant nonlethal effects.