Evaluating biodiversity and socio‐economic impacts of community‐led mangrove restoration: a case study from Kenya
Julius Sila, Orion McCarthy, Anthony Mbatha, Kisilu Mary, Johnson Nzai, Erastus Kithi, Leah Hays, Michael Stewart, Kevin Whilden, William Crosse, Henry Komu, Stanley Nadir, Edward MwamuyeAbstract
Introduction
Ongoing mangrove degradation has prompted restoration efforts to recover ecosystem services that support local livelihoods. Continued evaluation and learning are essential for adaptive management, yet studies rarely assess the combined biodiversity and social outcomes of restoration by integrating ecological monitoring with household‐level livelihood and perception data.
Objectives
We present insights from community‐led mangrove restoration in Kenya, evaluating biodiversity impacts of tree planting and community perceptions of mangroves and restoration.
Methods
We monitored 12 ecological metrics across a degradation gradient and conducted a survey of 383 local households.
Results
Vegetation metrics (canopy cover, aboveground biomass [AGB], diameter at breast height [DBH], tree density) showed clear trends across this degradation gradient, while invertebrate diversity and abundance did not. Previously restored sites were more similar to degraded than pristine sites, given the short time frame since planting (median 1.84 years, max 9 years). However, AGB, DBH, and tree density were significantly higher at older restoration sites, demonstrating the impact of restoration over time. Our household survey demonstrated community reliance on mangroves, with over half of respondents deriving greater than 25% of their income from mangrove‐dependent livelihoods (primarily fisheries). Over 90% of respondents reported improved quality of life from restoration, with 35 and 34% of restoration income used for education and food, respectively. Community members provided substantive recommendations, including forest patrols to prevent illegal logging, continued tree planting, and community education.
Conclusions
Our results reveal a temporal mismatch between biodiversity improvements and social benefits, highlighting the need for sustained investment in communities to maintain social benefits until ecosystem service gains from restoration become evident.