How many juvenile abalone are there? The example of Haliotis roei

We use population surveys of Haliotis roei on intertidal rock platforms at Perth, Western Australia to examine recruitment of juvenile individuals into the adult, fishable population. Despite intensive surveys conducted seasonally and over several years very few small H. roei were found. We propose the following life cycle for Haliotis roei: juveniles grow fast, reach adult size quickly, and survive for a number of years as adults. Recruitment of juveniles to the adult population is low, either through a steady annual maturation of juveniles or by substantial recruitment during an occasional good year.