Reproduction, fecundity, and growth of abalone (haliotis tuberculata Coccinea, Reeve 1846) in the Canary Islands

Abstract

The abalone, Haliotis tuberculata coccinea has been considered in the Canary Islands as a potential candidate species for aquaculture to restock its natural ecosystem. Because the study and development of artificial culture techniques require as much information as possible on natural populations, 20 monthly H. tuberculata coccinea samples were collected in the island of Gran Canaria between June 2005 and May 2007. Reproductive biology was assessed by histological techniques, and von Bertalanffy growth parameters were also estimated. Ovarian morphology of H. tuberculata coccinea showed 6 sexual cell stages during the oogenetic process and a group synchronous ovarian development. Its reproductive cycle is characterized by an annual spawning period throughout the entire year, although the maximum reproductive activity of this population was observed between August and February. Batch fecundity ranged from 85,749 (shell length (SL), 39 mm)-691,456 (SL, 62 mm), and a significantly higher fecundity rate was observed in individuals with an SL larger than 55 mm, suggesting that, to optimize egg production, this is the minimum broodstock size to be used in hatcheries. With regard to the population structure, the overall maleto-female ratio was 1:1.02 and the data of the size class analysis did not show any tendency. The von Bertalanffy growth parameters estimated for females and males were 72.5 and 78.8 mm in SL of asymptotic length, and 0.43 year-1 and 0.37 year-1 of growth rate.