The mass decline of amphibian populations poses a serious threat to global biodiversity and ecosystem health and stability. Batrachochytrium dendrobatidis (Bd), a pathogenic chytrid fungus, has contributed to the collapse of many amphibian populations globally and has caused the extirpation and extinction of hundreds of amphibian species. Bd causes chytridiomycosis and ultimately death in many adult amphibians, but it does not typically cause mortality in tadpoles. Yet, non-lethal exposure to Bd or the metabolites Bd produces may have adverse effects on tadpole growth and development. In this experiment, Cuban tree frog (Osteopilus septentrionalis) tadpoles were exposed to one of three treatments (live Bd, Bd metabolites alone, or an artificial spring water control; n = 31 tadpoles/treatment). Growth and development were monitored weekly for four weeks and mortality was observed daily.
Results/Conclusions
Tadpoles exposed to Bd metabolites alone developed faster than those exposed to live Bd or artificial spring water (p < 0.001). However, there was no difference in mortality, tadpole length or weight change between treatments (χ21 = 5.05, p = 0.08, χ21 = 1.28, p = 0.53 and χ21 = 1.67, p = 0.44, respectively). These results indicate that tadpoles developing in Bd contaminated water may be adversely affected during development even when they are not directly exposed to the pathogenic fungus Bd.