(P02-017-23) Heterogeneous Demand for Biodiverse Types of Fish and Seafood in Ghana

Objectives: Previous studies of food demand in Africa conceive of fish and seafood as one broad group, yet consumer preferences can vary across types. Biodiversity is one way to distinguish fish and seafood by ecological role, production source, and nutrient composition. The objectives of this study were to assess household demand for biodiverse types of fish and seafood and estimate demand responses to income and price changes.

Methods: The study uses nationally representative cross-sectional data collected from 13,922 households as part of the seventh round of the Ghana Living Standards Survey (2016-17). In this analysis, we used a multistage budgeting framework to specify Quadratic Almost Ideal Demand System (QUAIDS) models that consider biodiverse types of fish and seafood and account for sociodemographic and environmental factors. The first stage of the analysis estimated household demand for food versus nonfood; the second stage used those estimates to assess demand for general food groups, such as cereals and grains, fruits, and high protein foods. In the third stage, we specified a high protein food QUAIDS model that examined fish and seafood against red meat, poultry, eggs, and pulses and nuts. Then, we disaggregated fish and seafood into biodiverse types that reflect ecosystem origin (marine or freshwater) or genera/species (mackerel or herring) and repeated the third stage high protein food model.

Results: We found that households spent half of their high protein food expenditure on marine fish, followed by freshwater fish (12.8%) and red meat (12.5%). Elasticities of demand varied across biodiverse types of fish and seafood. Mackerel, herring, and sardines had lower income elasticities than shellfish, indicating consumer preferences for oily marine fish. Regarding own price changes, demand was generally rigid for fish and seafood, but especially for mackerel, sardines, tilapia, shrimp, and crab. Price increases for mackerel, herring, and sardines were not associated with demand increases for other types of fish or seafood; i.e., no other type was a substitute. Sardines were substitutes for eggs and shellfish for pulses and nuts.

Conclusions: By incorporating biodiversity into demand system models, we can assess heterogeneous household demand for different types of fish and seafood in Ghana.

Funding Sources: University of Michigan Dow Sustainability Fellowship