To improve nutrition, track fish from water to plate

The Majawa family's small portion of fish and tomatoes, needed to feed eight people, sits on a table at their home in the village of Masale during a drought in 2016 in Zomba, Malawi. (Credit: Andrew Renneisen/Getty Images)

A new method captures the true picture of how one of the world’s most-traded commodities—fish—moves from the water to the plate within a country.

The findings in Nature Food about sub-Saharan Africa reveal surprising gaps in the traditional supply-and-demand analysis of fish and opens opportunities to get the right fish to those who need it most.

And the innovations they deployed, the researchers say, can be useful anywhere.

“We know that all fish aren’t created equal in terms of containing the right nutrition for certain people in certain circumstances,” says coauthor Abigail Bennett, assistant professor at Michigan State University. “Effective policy needs new data that that reveals how variation in the supply, price, and form of fish in different places throughout a country shapes who can access that fish, with special attention to people who are poor and vulnerable to malnourishment.”

Existing data on food production indicate food supply, but not whether food reaches those who need it. Meanwhile, consumption data describe who ultimately ends up accessing food, but not where it came from or how it reached them. The group bridged that gap by looking at how fish moves across space through value chains after it is harvested and at household demographics.

They studied in Malawi in sub-Saharan Africa, looking at the trips two freshwater fish—small sardine-like usipa and medium-sized chambo, a variety of tilapia—took to end up at peoples’ tables, which meant understanding why fish ended up at certain markets, and whether people could afford them.

The little usipa is the bigger catch, both in volume and dollar value. It’s affordable, often sun-dried, and eaten whole. Chambo is usually eaten fresh and costs more.

The team, led by coauthor Park Muhonda when he was a postdoctoral researcher at Michigan State, surveyed more than 900 people throughout the fish food journey. He now is at Oregon State University.

The group found that usipa is distributed much more widely than chambo—available in 72 or the 79 markets surveyed across Malawi—while chambo was available in only 16 of those markets, which skewed toward urban areas. Usipa also packs more nutritional punch than chambo, being higher in protein, vitamins, and minerals critical to nursing women and their children.

But the group found that policies were championing the fancier chambo.

“While most fisheries policy in Malawi has previously focused on the larger high-value tilapia species, these results indicate the need for a shift in policy focus towards the small pelagic species to better support food security and nutrition,” says coauthor Edith Gondwe, a Michigan State PhD student in fisheries and wildlife.

“Our work on spatial analysis of fish in Malawi goes beyond Malawi and fish food systems,” says master’s student Emma Rice. “Most countries, including the United States, face food and nutrition security issues in different forms and contexts. This approach of spatial analysis of food systems could be adopted in any context to understand what types of food flow to which populations and through what mechanisms.”

The Michigan State University Alliance for African Partnership funded the work.

Source: Michigan State University