Can cage aquaculture save Malawi’s fisheries?

According to a 2022 assessment conducted by UNESCO on the impact of climate change on inland fisheries,” which focused on Lake Malawi, income from fishing activities in the region has declined over the past years, forcing fishers to travel long distances to find fish.

The report notes that to cope with climate and environmental shocks, locals have had to abandon the fishing industry for a more dependable income, such as farming.

Tricilla Tembo, 28, from Khuyu-Chilongola village in the Island district of Likoma in Malawi, has always depended on fish as a source of income for her livelihood.

However, she tells FairPlanet that fish capture has been a challenge in past years, affecting her business and survival.

“We thought it was just a bad year, but no. Fish catch has declined and remains scarce, with prices still going up. A 10-kilogram tin of small fish costs more than 20 USD, up from around 8 USD, and this is unaffordable to us,” said Tembo.

In Malawi, fish is the primary income resource for most local communities. It constitutes 7.2 per cent of the country’s GDP and employs 79,668 fishers with over 700,000 fish farmers.

Lake Malawi is one of the second deepest lakes in Africa and the ninth in the world.

The Lake has over a hundred fish species, with the famous Chambo fish (Oreochromis shiranus) dominating as the best in Africa and the World.

According to research by Carolyne Chinguo Munthali, climate change and overfishing practices have lowered the industry's performance compared to previous years.

Cage aquaculture

In response to this rapidly dwindling economy, youths in Likoma have found solace in a cage aquaculture initiative that has begun rejuvenating the island’s fishing industry.

Cage aquaculture is the growing of fish in existing water bodies enclosed in a floating net cage, which allows free flow of water. 

The Likoma Agri-Enterprise, a cooperative of 29 people, mostly women, is using cage aquaculture to restore fish availability and improve livelihoods. This shows how climate-smart solutions can be community-driven.

Likoma Project Manager Richard Banda said the project has stocked a floating cage (392.5m3) with 30,000 fingerlings (a juvenile fish about the size of a finger) and achieved some early success harvesting over 3 tonnes.

Banda believes the project is financially viable.

He told FairPlanet that after investing MK30 million (Over 17,000USD) in costs as a pilot, about MK43.7 million (250,000USD) will be realised in profit revenue within a cycle of 6 months, which will be in January 2026.

The Project Manager said the harvest will attract a price of 6.88USD per kilogram and is likely to offer more job avenues for the youths on the island.

Banda added that the initiative is the first high-capacity fish cage ever installed on Likoma Island. It was fabricated by Malawi-based aquaculture equipment manufacturer AquaLink Services, with support from the National Commission for Science and Technology (NCST) and Mzuzu University.

“This is a strategic response to overcome the threat of climate change and promote resilience, counter overfishing, and empower the local community. Traditional fishing is vulnerable to erratic weather patterns, rising temperatures, and changing lake ecosystems. Cage is a controlled environment, reducing dependence on wild stocks affected by climate-induced migration.

“Lake Malawi has seen a sharp decline in fish populations like Oreochromis spp. (Chambo), largely due to overfishing. By cultivating fish in cages, communities can reduce pressure on wild stocks while meeting nutritional and economic needs,” said Banda.

Scaling the solution

Banda said the initiative can also boost food security because Malawi relies heavily on fish as a protein source. Expanding cage aquaculture could help meet growing demand, especially in areas where traditional fishing is no longer viable.

“The initiative is environmentally adaptable, unlike pond aquaculture, which requires land and water sources; cage systems can be deployed in lakes across the country, making them ideal for Malawi’s geography,” said Banda.

A youth-led inititiative

Asante Mankhokwe, chairperson of Likoma Agri-enterprise, a group of 29 youths aged 18 to 35 (15 women and 14 men) running the initiative, said the initiative is a big boost considering how fast the fish resource is depleting.

“We have been living in an environment where we depend so much on capture fisheries, which keep depleting. However, with this initiative, we have a steady source because the fish we stock are the same that we are going to harvest, unlike in the capture fishery, which is very inconsistent.

 “The initiative is very profitable because we are likely to harvest more, and maybe 600 times more than the capture fishery, according to our stocking density of 10 fish per cubic volume, which we have used. If this started way back, it would have already transformed our lives and even the economy of Malawi,” said Mankhokwe.

He said the community has welcomed the initiative so far, and the group is building on sustainability plans because they are looking forward to having over 15 cages to improve the supply chain for exports.

What are the experts saying?

Senior Deputy Director of Fisheries in the Department of Fisheries in Malawi, Jacqueline Kazembe, said Cage aquaculture offers a promising alternative to address declining fish catches caused by overfishing and climate change.

“This is a system of rearing fish in floating cages placed in natural water bodies such as lakes. This reduces costs linked to land acquisition and water management compared to pond aquaculture. Cage systems achieve much higher yields per unit volume, enabling more efficient fish production.

“Secondly, this system is also less vulnerable to climate-related challenges such as prolonged dry spells, which often disrupt pond-based aquaculture. When well-managed, cage aquaculture can provide a sustainable supply of fish to supplement dwindling wild stocks and help restore balance between capture fisheries and aquaculture,” said Kazembe.

She said, however, there is a need to scale up the initiative by strengthening infrastructure such as access roads, cold storage and processing facilities to link producers to markets.

“There is a need to expand research and innovation in feed production, breeding, and disease management, build capacity through training of farmers, extension workers, and local communities and to create a supportive policy and regulatory environment that attracts private sector investment and public–private partnerships.

“With these measures, cage aquaculture can expand beyond a few pilot sites and become a large-scale contributor to food security, employment creation, and export earnings,” she said.

Potential risks of cage aquaculture

Despite its promise, cage aquaculture also carries ecological and social risks.

One ecological downside, Kazembe said, is that the nutrient build-up from excess feed and fish waste may degrade water quality. At the same time, poorly sited cages can disrupt ecosystems or compete with other water users.

Secondly, she said strong winds and storms may damage cages, releasing farmed fish into the wild and causing genetic mixing or competition with native species.

“On social aspects, theft and vandalism are common challenges, often leading to conflicts with local communities. Cage aquaculture can also exclude other users of the lake, such as artisanal fishers, if not properly coordinated.

“To manage these risks, environmental and social impact assessments (ESIAs) must be conducted before establishing cage sites. Continuous monitoring, strict biosecurity measures, and community engagement are essential to ensure that aquaculture development is inclusive, safe, and environmentally sustainable,” said Kazembe. 

Image by Leonard Masauli.