Aquaculture – the farming of fish, shellfish, and other aquatic organisms – is one of the most crucial sectors in global food production. However, in recent years, it has been struggling to meet the growing demand for seafood and has faced environmental challenges.
Professor Sunil Kadri of Charles Darwin University in Australia (CDU) shares some of his insights on the subject matter.
“Fisheries and aquaculture have been carried out for thousands of years, with fisheries having dominated supply historically, as it is a form of hunting, which has grown to an industrial scale,” he explains.
“However, despite the growth, fisheries have not been able to meet demand sustainably, so aquaculture has had to grow to fill the gap.”
The largest and fastest-growing producer of cultured fish is China, where freshwater fish dominate growth and volume. Other major producers are also growing their production, and they are often dominated by marine fish/crustaceans, such as Japan, Thailand, Vietnam, India, Norway, Ecuador, Indonesia, and Chile.
Several industry challenges include environmental impact, disease and parasite management, feed sustainability, genetic pollution, limited resources, trade barriers, and climate change.
Environmental impact
Aquaculture can lead to habitat destruction, water pollution, and disruption of local ecosystems.
Sustainable practices like Integrated Multi-Trophic Aquaculture (IMTA) can mitigate environmental impacts. IMTA combines different species that can benefit each other and reduce waste.
Additionally, Recirculating Aquaculture Systems (RAS) recycle water and minimise discharge, promoting a cleaner and more sustainable approach to aquaculture.
Disease and parasite management
High-density farming conditions make fish and shellfish susceptible to diseases and parasites, which can spread rapidly. Improving biosecurity measures is key to preventing disease outbreaks.
Regular health monitoring, vaccination programs, and selective breeding for disease-resistant species can help maintain the health of aquaculture stocks. Ensuring optimal water quality also plays a critical role in disease prevention.
Feed sustainability
Traditional fish feed relies heavily on wild fish stocks, leading to sustainability concerns. Developing alternative feed sources is essential.
Plant-based proteins, insect meals, and by-products from agriculture and food industries can reduce reliance on wild fish stocks.
Escapes and genetic pollution
Farmed fish escaping into the wild can lead to genetic pollution and competition with native species. Enhancing containment systems and farm infrastructure is crucial to preventing escapes.
Using sterile or triploid fish can minimise the risk of genetic impact on wild populations.
Resource use and efficiency
Aquaculture requires significant water, energy, and feed inputs, which can strain local resources.
Optimising resource use through efficient farming techniques and technologies is vital. Water recycling and waste management systems can significantly reduce resource consumption and environmental footprint.
Market access and trade barriers
Due to regulations and consumer preferences, aquaculture products may face trade barriers and limited market access. Compliance with international standards and certifications for sustainable and responsible aquaculture is essential.
Climate change
Climate change impacts, such as rising temperatures, ocean acidification, and extreme weather events, pose risks to aquaculture operations.
Developing adaptive strategies is key to mitigating climate change impacts. Selecting resilient species, adjusting farming locations, and implementing climate-smart practices can help aquaculture operations adapt.
Silver linings
On the brighter side, the UN Food and Agriculture Agency (FAO) said that for the first time, farmed aquatic production has exceeded the catch from traditionally captured fisheries, underscoring hopes that aquaculture can meet the growing global demand for seafood.
FAO said aquaculture production hit an unprecedented 130.9 million tonnes in 2022, of which 94.4 million tonnes were aquatic animals – 51 per cent of the total aquatic animal production.
“These numbers demonstrate the potential for aquaculture to feed the growing world population,” said Manuel Barange, assistant director general of the FAO.
“It’s been the fastest growing food production system (in the world) for the last five decades.”
However, the report also pointed out that the bulk of aquaculture production is concentrated in just 10 countries – China, Indonesia, India, Vietnam, Bangladesh, the Philippines, South Korea, Norway, Egypt and Chile – urging the need to develop the industry in other regions, particularly in Africa.
While some critics have raised concerns about the environmental impact and risks of disease and invasive species associated with aquafarming, FAO emphasises that proper regulation and monitoring can mitigate these challenges.
Global per capita annual consumption of aquatic animal foods – a key source of protein for millions worldwide – totalled 20.7 kg in 2022, up from 9.1 kg in 1961 and was set to rise further in the years ahead.
Barange added, however, that many larger commercial fisheries were being well managed, including tuna stocks, which are now approaching 90 per cent sustainability.
“This is a remarkable improvement over the last decade,” he concluded.
