Survival and Breeding Structure in a Population of Ambystoma maculatum

Abstract

Marking-recapture records of Ambystoma maculatum taken during 5 consecutive breeding migrations at a single pond have been used to estimate population parameters. Male survival is higher than female survival. The proportion of animals breeding each year is slightly higher for males. Sex ratios in the breeding population reveal more males than females, confirming the higher male rates. Sex ratios in identifiable groups of individuals increased in favor of males during the study. Survival rates and proportions breeding were used to compute sex ratios that compare well with field sample values.