POPULATION ECOLOGY OF THE AUSTRALIAN FROG CRINIA-SIGNIFERA - ADULTS AND JUVENILES

A population of the common Australian frog Crinia signifera Girard, 18 53 was studied over a 3.5-year period at a site near Bridgewater in So uth Australia. In this population, C. signifera are long lived and ite roparous, with some individual males and females participating in at l east four consecutive breeding seasons. Adult survivorship was high (u p to about 70% per annum) for both males and females. Metamorphosis oc curred from October to January and some individuals reached maturity w ithin a year. However, most individuals reached maturity in the second breeding season following metamorphosis. Survival of juveniles ranged from 5 to 72% per annum, with individuals emerging early having highe r survival than those that metamorphosed late. However, it was not cle ar whether increased survival was associated with early emergence or l arge size at emergence. The data support the argument that iteroparity is favoured in situations in which preadult mortality is higher and l ess predictable than adult mortality.