Aquaculture May Reduce Rural Poverty, Income Inequality

Since 2014, more than half of all fish consumed by humans have been farmed rather than caught in the wild. Aquaculture — which includes the farming of not only fish, but also mollusks, shellfish, algae, seaweed and more — has grown exponentially for decades and has emerged as a major global economic activity. While aquaculture has certainly generated substantial wealth, the distribution of this wealth, particularly in poor and rural areas, remains largely unstudied.

In an article recently published in World Development, authors Ben Belton of Michigan State University and Mateusz Filipski of the University of Georgia attempted to fill the economic data void surrounding rural aquaculture. Through a survey of 1,102 households in a fish-farming region of Myanmar, the researchers gathered information about aqua and agricultural employment, practices, yields and incomes. This data was matched to a digital GIS map of fish ponds identified using satellite images. The researchers delineated an “aquaculture cluster” encompassing roughly 42 percent of Myanmar’s total fish pond surface area. Focusing on these zones, the authors constructed a Local Economy-Wide Impact Evaluation (LEWIE) model to assess the economic effects of aquaculture on both households and communities.

In Myanmar, a majority of farmed fish are raised in inland ponds that are dug out from converted croplands located within broad river deltas. These ponds range from small, family-managed pools to large industrial enterprises. Ponds can be stocked with a variety of fish; native carp are the most common, followed by catfish, tilapia and pacu. Using the LEWIE model, the authors evaluated the labor and income effects of increased fish farming among defined subgroups of households and communities. To do this, the researchers simulated the impact of a crop-to-pond transition within a rural area, conditioning for variables such as pond size and type, labor and technology inputs, and ownership. The model also enabled the authors to examine spillover effects of fish farming—the economic consequences of aquaculture for rural families who don’t operate fish ponds themselves.

The LEWIE model-based analysis showed that land used for aquaculture is more economically productive than land used for farming, yielding 4.7 times the revenue of a farm plot of the same size. The model also revealed that aquaculture creates more demand for labor, requiring an average of 94 days of labor per acre per year, compared with 24 days for cropland. In addition, the researchers found that fish farming generates significant positive spillover effects in rural economies, raising the average incomes of nearby community members who do not own their own ponds.

The authors noted that these spillovers reduced local income inequality in communities where fish ponds tended to be small — an effect they attributed to small-farm owners’ propensity to engage local labor and use local materials. Large industrial ponds, on the other hand, are more likely to use externally sourced inputs, and they were shown to increase local inequality.

Belton and Filipski suggested that aquaculture has significant potential as a tool to reduce global poverty. Still, their research indicates that before promoting the conversion of cropland to ponds, policymakers should consider all possible implications for local income inequality and land distribution.

This conclusion does not take into account environmental externalities—good or bad—associated with aquaculture. On the positive side, aquaculture reduces pressures on wild fish stocks, benefitting natural ecosystems. Moreover, compared with fisheries, farming generates less waste, and it can even yield useful byproducts such as fertilizers. On the negative side, aquaculture contributes to water pollution by introducing large quantities of chemically treated feed and contaminated animal waste to otherwise clean water systems. In addition, species that escape containment can pose serious threats as invasive species in non-native habitats. Aquaculture is also responsible for habitat loss, particularly in coastal mangrove forests; so far, about 35 percent of these forests have been cleared for human activity, including shrimp farming.

For communities in the developing world, aquaculture may only help to relieve poverty temporarily—in the long run, environmental degradation could make things far worse. If the current environmental costs of aquaculture outweigh the benefits (as one study suggests may be the case), then more research would be needed to determine how to establish aquaculture systems that are economically profitable, socially equitable, and environmentally sustainable.

Article source: Belton, Ben and Mateusz Filipski. “Give a Man a Fishpond: Modeling the Impacts of Aquaculture in the Rural Economy.” World Development 110 (2018): 205-23.

Featured photo: cc/(epixx photo ID: 491348038, from iStock by Getty Images)