Ageing and growth of the endangered midwife toad Alytes muletensis

A better understanding of the demography of endangered amphibians is important for the development of suitable management and recovery plans, and for building population viability models. Our work presents, for the first time, growth curves and measurements of mean longevity, growth rates and age at maturity for the Vulnerable midwife toad Alytes muletensis. Von Bertalanffy growth models were used to estimate longevity and growth rate parameters. Females had a mean (+/- SD) longevity of 4.70 +/- 0.19 yr, significantly higher than that of males (3.24 +/- 0.10 yr). The maximum estimated longevity was 18 yr for both males and females. The age distribution indicated that males reached sexual maturity at the age of 1 yr, and most females at 2 yr. There were significant differences in growth rate between sexes, with higher values in females during the first 4 yr of life, and similar values in both sexes thereafter. These life-history traits were compared with equivalent measures in the closely related amphibian genera Bombina and Discoglossus.