The Distribution and Zonation of Barnacles Around Intertidal Shores of Penang Island

The intertidal shores around Penang Island were surveyed for the distribution of barnacles from 14th November 2011 to 31st January 2012. The sampling was done by using 20 cm x 20 cm transect to count the barnacles. Three replicates were taken for each zonation available of the intertidal areas; i.e. upper, middle, and lower zonations, at every sampling site. From the result, three species were identified, including Euraphia withersi and Chthamalus malayensis from Family Chthamalidae, and Balanus amphitrite amphitrite from Family Balanidae. Chthamalus malayensis was found to be most abundant among the three species with 44.24% of total population; and Tg. Tokong recorded the highest abundance of this species (28.22%). This was followed by Euraphia withersi with 38.77%; which was found to be densely populated at Gelugor (21.92%). Balanus amphitrite amphitritewas least abundant with only 16.99% and mostly found at Gurney Drive (26.24%).The distribution of the three species of barnacles also varied among the sampling locations. Gertak Sanggul recorded the highest relative abundance of all three species of barnacles at 18.01%; while the location with the least relative abundance of barnacles is Queensbay with 0.33%.Based on ‘Non-Supervised Artificial Neural Network' (ANN), distinct zonation was observed where Chthamalus malayensis was more dominant on the upper zonation; Euraphia withersi on the middle zonation; and Balanus amphitrite amphitrite on the lower zonation. The interaction betweenbarnacles with other barnacles leads to competitive exclusion and niche partitioning which created zonations among the species. Interspecies interaction that brought by predation also played a part in the distribution of barnacles. Apart from that, the distribution was affected by the sampling sites and humanactivities; such as embankment, land reclamation, and residential development

The Potential Use of Probiotics for Sustainable Aquaculture of Mud Crab, Scylla SP.

The mud crab (Scylla) is a commercially important crustacean, as there is a large demand in many Southeast Asian countries. Currently, one of the main bottlenecks to the expansion of Scylla aquaculture is the inconsistent and low production of hatchery juveniles. One major challenge to overcome at the hatchery level is disease issues caused by bacteria. The use of probiotics to outcompete pathogenic bacteria is being tested in the industry as a better disease prevention method in Scylla aquaculture compared to antibiotics, and is getting more recognition in aquaculture to reduce bacterial issues. The current review discusses mudcrab farming activities in Malaysia and the scope for using probiotics in Scylla aquaculture, as this is a potential way to increase survival rates in a long term sustainable way