Temporal variation in adult sex ratio in a population of the terrestrial salamander Speleomantes strinatii

The adult sex ratio of a population of Speleomantes strinatii living in an underground habitat was studied for 12 consecutive years by temporal removal sampling. Capture probabilities of males (0.72) and females (0.69) were similar and yielded highly reliable sex ratio values. The adult sex ratio, expressed as the proportion of males, was significantly male-biased (mean 0.57, bootstrap 95% confidence intervals 0.53–0.65) and remained relatively constant during the study. A negative relationship was observed between adult sex ratio in one year and the abundance of juveniles in the following one (P=0.02), suggesting that an excess of males limited juvenile recruitment and therefore influenced population dynamics.