Aquaculture-based Enhancement and Restoration of Many-colored Abalone Resources (Haliotis diversicolor Reeve, 1846) in Bach Long VI National Marine Protected Area, Vietnam

Abstract

Many-colored abalone (Haliotis diversicolor) is high commercial species in Vietnam. Meanwhile, these resources have been over-exploited, thus, artificial breeding was implemented to restore natural abalone resources. After sourcing the broodstock, many-colored abalones were stimulated to reproduce during October -December 2013 at the Abalone Seed Center in Bach Long Vi, Hai Phong City. The results showed that veliger larvae developed from 11h - 36h after breeding. Abalone juveniles reached to 4.5 mm (shell length) at the age of 42 days. Survival rate of abalone juveniles 1-2 mm (28 days old) was 0.92%, 3.80%, and 24.00% at larvae densities 7.5, 6.8, and 1.6 larvae/cm super(2) algae board, respectively. After 2 months (October - November), 30,000 juveniles of 4.5 mm shell length; 33,800 juveniles of 3 mm shell length; 45,500 juveniles of 2 mm shell length; and many small larvae were collected at the Bach Long Vi Abalone Seed Center. More than 6,000 juveniles of 4.5 mm shell length were released to Bach Long Vi National Marine Protected Areas for conservation in April 2014. The restoration assessment was briefly carried out in June 2015, and found that almost all individuals were found to have average shell length of 3.4 cm in Bach Long Vi National Marine Protected Area. This is an initial achievement of aquaculture and juvenile rearing to release and protect the many-colored abalone resources in Viet Nam.