Effects of elevated salinity on Cuban treefrog Osteopilus septontrionalis aldosterone levels, growth, and development

Abstract

ABSTRACT Amphibians are increasingly challenged with salinization due to factors such as elevated sea level associated with climate change, the use of road salts, and lowering of water tables. Aldosterone is a steroid hormone that is produced by the adrenal cortex and is involved in osmotic regulation and may play an important role in amphibian acclimation to elevated salinity. We studied the effects of salinity on growth, development, and aldosterone levels in Cuban treefrog (Osteopilus septentrionalis) tadpoles. Gosner stage, growth rates, and aldosterone levels were determined for tadpoles among three salinity treatments (1.0, 2.5, and 3.5 ppt) over a six-week period. It appears that Cuban treefrog tadpoles have the ability to respond to high salt levels with decreased aldosterone secretion; however, in order to survive high salt concentrations, trade-offs in growth and development must occur to regulate osmotic functions.