Many small-scale farmers in Malawi keep fish as an aside to crop production amid falling crop yields.
Typically, they usually use recycled fingerlings and seldom use supplementary feed and new innovations to boost production.
This slows the growth of fish farming though up to 25 percent of the country’s land is billed suitable for fish farming.
The favourable sites remain hugely underutilised as the National Fisheries and Aquaculture Policy envisages the country producing 10 000 tonnes of fish per year, up from the current 3 600 tonnes.
This calls for increased research and uptake of high-yielding innovations.
Trials by Mzuzu Aquaculture Centre show that large, deep ponds bring big fish and yields.
For eight months, the researchers monitored the effectiveness of big ponds in the wetlands of the Green City. In December, they yielded 6.6 tonnes from a one-hectare pond.
According to lead researcher David Mbamba, the catch earned K8 million in profit—minus labour and inputs’ costs.
“This makes large-deep ponds one of the strategies that boost fish production within a short period of time,” he states. “If fish farming was done this way, it would revolutionalise the economy and improve our livelihoods in no time,” said the scientist.
The pond of at least 1000 square metres measures three metres deep. The researchers stocked it with six chambo fingerlings of 10 gramme body weight per square metre.
The trial capitalised on natural aquatic productivity as well as high-quality floating feed for increased yield.
Mbamba said the technology requires attention to detail, including water quality, fertilisation, feeding, predation and disease control. This makes it method labour-intensive, he stated.
The researchers invested K7.8 million in labour and farm inputs, but sold the eight-month-old catch at K16.6 million.
The fish, which weighed 250 to 400 grammes each, sold at K2 500 apiece.
“This is amazing,” said Mbamba. “Which crop enterprise can give you such a profit margin from the same piece of land?”
After announcing the results, Moffat Manase, chief fisheries research officer in the Department of Fisheries, said the technology could transform fish farming in the country.
He urged fish farmers to embrace the big pond to enhance their yields.
Manase said the department would accelerate the adoption of the strategy by providing quality fingerlings, extension services and research farmers can use to commercialise aquaculture.
Professor Emmanuel Kaunda, from Lilongwe University of Agriculture and Natural Resources, says fish farming has enormous potential to improve livelihoods and the national economy.
“Malawi’s aquaculture can perform wonders if fish farmers and private sector players embrace it as a commercial venture using modern technologies using improved local strains and quality feed,” he says.
The government has scrapped value-added tax from fish farming inputs, including feed, to transform fish farming into big business.
However, Karonga fisheries officer William Chirwa said despite the high profit margins, the massive ponds demand large portions of land amid rapid population growth and shrinking land size per person.