It is said that aquaculture is believed to have the potential of meeting the shortage of wild fisheries production. In this context aquaculture should be based on the core principles of ecologically sustainable development. But some aquaculture practices do not always conform to the environmental standards.
According to Universiti Malaysia Sabah (UMS) Borneo Marine Institute director, Professor Dr Saleem Mustafa opined that pollution from fish farms can be divided into two categories – organic and chemical. He added that the prime source of organic pollution is in the form of fish excrement and unconsumed feed, and also from dead fish and fish waste. He explained that the nutrients such as nitrogen and phosphorus contained in the organic waste stimulate the growth of marine algae, which deplete oxygen when they die and decompose.
Then the accumulated waste can smother the marine organisms and produce oxygen depleted conditions at the seabed, while at the same time releasing methane, hydrogen sulphide and carbon dioxide. It is observed that the chemical pollution from farms includes antibiotics and other chemicals substances used to keep the cultured fish free from disease and to promote growth.
Dr Saleem stressed that therefore there is a need to focus more on disease management in aquaculture in Sabah. He told that this problem, to some extent, can be addressed by using high health or specific pathogen free (SPF) for exclusion of the possibility of vertical transmission of infection.
