As fish production in northern waters nears full capacity, S’pore looks to the south to boost supply
Written by: Audrey Tan / Science and environment correspondent for Straitstimes.com
Photography credit: Alphonsus Chern
The fish-rearing capacity of the narrow body of water to Singapore’s north, where almost all the nation’s offshore fish farms are located, could soon reach maximum production levels as the country scales up local food production.
So to further boost the Republic’s resilience against disruptions to global supply chains, as what is happening amid the ongoing COVID-19 outbreak, the authorities have now set their sights on the nation’s southern waters for aquaculture.
A spokesman for the Singapore Food Agency (SFA) said the agency has conducted a broad scan of the southern waters for potential aquaculture sites for sustainable farming systems. “Various spatial, production and environmental constraints were taken into consideration to determine potential sites,” she added.
There is now only one deep-sea fish farm in the southern Singapore Strait, Barramundi Asia, which occupies two sites. Over in the Johor Strait are 108 coastal fish farms that make up the bulk of Singapore’s 110 licensed sea-based fish farm sites.
Last year, local farms produced about 4,700 tonnes of fish – or about 10 per cent of total consumption.
The Straits Times has learnt that a study commissioned by SFA has shown that certain sites north of the mainland are nearing carrying capacity, which indicates maximum production levels.
Production above the maximum levels could result in poorer water quality within the farming zones and impact farm productivity, the SFA spokesman said.
But the study also found that overall, implementing management measures would support higher production levels of the aquaculture zones, an SFA spokesman said.
She did not elaborate on what these measures could be, but said the agency would be engaging stakeholders like nature groups and farmers as part of its planning and assessment for the development of the aquaculture zones in the Johor Strait.
Professor Dean Jerry, an aquaculture expert, said expanding aquaculture zones could dramatically increase home-grown aquaculture products, especially as companies move towards a high-volume, industrial-scale production model.
“Marine aquaculture if done on an industrial scale is one of the most efficient animal protein producing sectors available,” said Prof Jerry, director of the Tropical Futures Institute at James Cook University Singapore.
“Opening up new areas for aquaculture and encouraging innovative and industrial-scale operators to take up sites could double current production volumes very quickly once farms are established.”
But industrial aquaculture also comes with its challenges, he said, pointing to factors such as the need for good disease control and tailoring fish feed to the species being reared in order to achieve maximum productivity.
The marine environment the fish are reared in is also important, he said. Unlike land-based fish farms, where fish are reared in enclosed tanks, many offshore fish farms keep their fish in netted pens in the sea, which means the fish are exposed to the surrounding environmental conditions.
Prof Jerry said that in Singapore, the carrying capacity of a body of water for aquaculture depends on how the marine environment copes with additional pressure.
Considerations include whether there is enough dissolved oxygen in the water to accommodate more fish, or if the ecosystem can process fish waste or uneaten food in a way that does not cause any imbalance to the water’s nutrient level.
An imbalance in the amount of nutrients such as nitrogen, which is present in fish waste, could cause harmful algae blooms. These blooms have in the past resulted in mass fish deaths in Singapore.