What if Traditional Ecological Mangrove Knowledge Eroded over Decadal Time Scales?

Long-term monitoring of mangrove ecosystem changes and their impact on local communities is challenging due to the need for decades of fieldwork. Gazi Bay, Kenya, has become a model site for studying long-term mangrove dynamics and social-ecological transitions, thanks to ongoing scientific research since the 1980s. This study analyzes mangrove use in the 2000s, 2010s, and 2020s through 262 semi-structured ethnobiological interviews covering mangrove utilization, fisheries, and environmental perceptions. Findings reveal a local ecological taxonomy based on mangrove species traits, with usage patterns evolving over time. While some species remained constant or increased in use for construction and fuelwood, others declined significantly in applications such as construction, medicine, material treatment, and food/fodder (including fisheries). These shifts, along with changing gender roles, signal a loss of Traditional Ecological Knowledge (TEK). Community members reported perceived increases in mangrove cover, attributing them to natural regeneration, planting efforts, cutting bans, and conservation awareness. Continued research is essential to inform sustainable management, understand evolving human–mangrove relationships, and navigate the trade-offs between conservation and TEK erosion.