Plasma androgen levels during male parental care in a tropical frog ( Eleutherodactylus)

Abstract

Males of the Puerto Rican frog Eleutherodactylus coqui practice parental care of terrestrial eggs throughout embryonic development (17–26 days). Parental care is associated with marked changes in male behavior, including the cessation of normal calling activity (necessary for mate attraction) and reduction of egg cannibalism. To analyze the relationship between parental behavior and androgens, blood was collected from male frogs in the field and plasma analyzed for total androgens. Parental males had significantly lower androgen levels than both nonparental, calling males, and amplectant (mating) males. The decline in circulating androgens between the sexually active state (calling and mating) and the parental care state was fairly rapid (<12 hr). Androgen levels did not differ among parental males at different stages of the parental care period.