Overfishing, marine ecosystem degradation and fisheries sustainability in Zanzibar: Evidence from fishers’ perceptions of coral reef and mangrove decline

Abstract

This study investigated the perceptions of small-scale fishers in North Coastal Zanzibar regarding overfishing and marine ecosystem degradation, which threaten their livelihoods dependent on fish and healthy marine habitats. Conducted through a cross-sectional quantitative design, the research surveyed 150 fishers across five districts. Key findings reveal significant perceptions of changes in fish abundance (χ²(1) = 8.64, p = .003, φ = .24) and a very strong awareness of fish migration and distribution changes (χ²(1) = 106.29, p < .001, φ = .85). Fishers reported a notable increase in their numbers (χ²(1) = 138.24, p < .001, φ = .96), primarily attributed to unemployment in other sectors (χ²(1) = 86.86, p < .001, φ = .77). Interestingly, population growth did not significantly contribute to overfishing perceptions (χ²(1) = 0.24, p = .624, φ = .04). While coral and mangrove deterioration were not dominantly reported, drag-net fishing was identified as a major cause of coral degradation (χ²(1) = 17.86, p < .001, φ = .71). The reduction of fish due to habitat degradation was overwhelmingly acknowledged (χ²(1) = 109.30, p < .001, φ = .95). The study concludes that the sustainability challenge in fisheries is driven by increased fishing pressure and destructive practices rather than solely by population growth. Recommendations include sustainable fisheries governance, alternative employment, enforcement of regulations, and habitat protection to support fishing communities.