A new framework on climate-induced food-security risk for small-scale fishing communities in Tanzania

Abstract

Food insecurity is a pressing issue facing our world, particularly affecting coastal communities who rely on marine resources. The problem is further compounded by the rapidly changing climate, a deteriorating environment and growing human populations. It is essential to evaluate this issue accurately to reduce risk and improve the situation of coastal communities, especially in countries with less socioeconomic development. To this end, we develop a food security social-ecological risk assessment framework for developing communities in coastal areas of the Western Indian Ocean facing a changing environment. The framework integrates local ecological knowledge, expert scientific opinion, survey data, and satellite sea surface temperature (SST) and chlorophyll-a observation. We conducted a local-scale case study in four regions in Tanzania; Mafia, Pemba, Tanga, and Unguja, revealing that they face moderate to high risk levels of food insecurity. The highest risk was observed in the island communities of Pemba and Unguja, while the communities of Mafia and Tanga had the lowest risk due to lower exposure and sensitivity to climate change. Our results show that recognizing the key differences across risk components is crucial in identifying effective intervention strategies for local practitioners. This study highlights the need for detailed assessments to provide accurate information on local-scale food security dynamics, specifically when assessing impacts induced by environmental and climatic changes.

Supplementary information: The online version contains supplementary material available at 10.1007/s12571-024-01472-x.

Keywords: Climate change; Food security; Risk assessment; Small-scale fisheries; Western Indian Ocean.

Fig. 1

Study region. The four study sites of Mafia, Pemba, Tanga and Unguja are highlighted in dark

Fig. 2

Climate-Induced Food Security Risk Framework (CFSR). The figure illustrates the conceptual framework that was developed and utilized to evaluate the climate-induced food security risk in four coastal communities in Tanzania. The left-hand figure displays the total ecological risk to the resources, which is nested within the overall final CFSR framework on the right-hand side. This ecological risk resource serves as one indicator for “hazard.” To calculate the ecological risk resource, four dimensions are considered: resource hazards (EH1 “Sea surface temperature (SST)” & EH2 “Primary Production – PP”), resource exposure (EE1 & EE2), resource sensitivity (ES1 & ES 2), and resource adaptive capacity (EA1 & EA2). Four dimensions are used to describe the overall CFSR: social hazard (SH1, SH2, SH3), social exposure (SE1 & SE2), social sensitivity (SS1 – SS8). The darker rectangles in the figure enumerate each indicator for every dimension

Fig. 3

The proportion of fish per functional seafood group consumed by communities

Fig. 4

Community directly and indirectly dependence on fishing. Boxplots of two survey questions are presented for each community, which relate to their reliance on fishing. The first question, figure A, concerns the proportion of fish consumed as the primary source of protein in the community. The second question, figure B, pertains to the proportion of income earned from fishing. The figure displays significant differences between the communities, represented by the brackets and p-value

Fig. 5

Education, wastewater disposal, and food security by communities. Each plot displays questionnaire responses concerning three questions regarding the social aspects of the community. Question A represents the education level of the fishers in the community (left plot). Question B pertains to the available wastewater disposal types in the communities (center plot). Question C explores the possibility of families within the community being able to feed themselves without relying on fishing (right plot)

Fig. 6

Overall scores of climate-induced food security risk to the four Tanzanian communities

Fig. 7

Communities risk profiles. Risk profiles depicting the inherent risk components based on scores of vulnerability and exposure. Based on Thiault et al. (2019)