METAMORPHOSIS AND POSTLARVAL GROWTH OF ABALONE HALIOTIS RUFESCENS
IN A MEXICAN COMMERCIAL HATCHERY
RICARDO SEARCY-BERNAL,1* ESTEBAN PÉREZ-SÁNCHEZ,1
CASANDRA ANGUIANO-BELTRÁN1 AND ROBERTO FLORES-AGUILAR2
1Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Ensenada,
Baja California, México; 2Centro de Investigación y Desarrollo de Recursos y Ambientes Costeros i-mar,
Universidad de los Lagos, Puerto Montt, Chile
ABSTRACT Metamorphosis induction and postlarval growth of the red abalone (Haliotis rufescens) were evaluated in a
commercial farm of Baja California, México. This hatchery settles larvae with gamma-aminobutyric acid (GABA, 1-mM final
concentration) and culture postlarvae in 250-L tanks placed in a four-story structure inside a building with artificial illumination.
Eight tanks (four at the top and four at the bottom of a culture structure) were sampled during four months after settlement.
Upper tanks received more light than the lower tanks (means of 727 and 217 lux, respectively) and had a higher mean water
temperature (14.9C and 14.4C, respectively). Estimates of metamorphosis induction were highly variable (37% to 99%) and
mean values were higher in lower (76%) than in higher (54%) tanks. Potential causes of this unexpected variability are discussed.
There was a significant positive linear relationship between metamorphosis induction and early (7-day) postlarval survival.
Average postlarval growth rates were also highly variable among tanks (37–63 mm/day) and slightly higher in upper than in lower
tanks (60 and 52 mm/day, respectively). During the sampling period, growth variability was positively associated with water
temperature changes, especially after the formation of the first respiratory pore when growth increased abruptly.
KEY WORDS: postlarvae, metamorphosis, growth, abalone, Haliotis rufescens
In abalone (Haliotis spp.) hatcheries, metamorphosis induc-
tion and postlarval culture are key issues, because most
mortality occurs during these