Mangrove forests across the world are increasingly seen as frontline defenders against climate change, coastal erosion and extreme weather. Yet despite growing investments and global pledges, a large number of mangrove restoration projects continue to fail. New evidence from projects spanning Africa, Asia and the Americas shows that success often depends on an overlooked factor strong intermediary organisations that bridge the gap between local communities, science and funding.
Across tropical and subtropical coastlines, mangroves protect shorelines from storm surges, store large amounts of carbon and support fisheries and livelihoods. However, experts estimate that up to 70% of mangrove restoration projects in some regions have low survival rates, with seedlings dying or sites degrading further over time. Scientists say this is rarely due to lack of intent, but rather a lack of long-term planning, technical expertise and sustained resources at the community level.
Many restoration efforts are led by small local groups that have deep knowledge of their environment but limited access to funding, monitoring tools and scientific guidance. According to mangrove ecologists, planting efforts often fail when projects focus on numbers of saplings rather than restoring the right ecological conditions, such as tidal flow, soil salinity and hydrology.
In several regions of Southeast Asia and Latin America, poorly designed restoration has resulted in mangroves being planted in unsuitable zones, leading to mass die-offs. Social factors also play a role. Without stable income, community members may disengage once short-term funding ends, while illegal logging and coastal development continue to threaten restored sites.
Researchers stress that mangrove restoration is as much a social and economic challenge as it is an ecological one. Successful projects must consider land tenure, community dependence on mangroves and alternative livelihoods alongside planting strategies.
The growing role of intermediaries
To address these gaps, a growing number of environmental nonprofits are acting as intermediaries organisations that do not directly run restoration projects, but support local partners by providing funding, scientific expertise, monitoring systems and storytelling capacity.
One such organisation, Seatrees, has supported mangrove restoration efforts in Kenya, Mexico, Indonesia and the United States over the past five years. Rather than leading projects from the outside, the organisation works with local NGOs and community groups, helping them scale up activities while improving technical quality and accountability.
In Kenya, where its work is most advanced, Seatrees and its local partner have supported more than 30 community groups to restore mangroves across more than 750 hectares. Communities have planted over one million seedlings, maintained nurseries, dug trenches to restore natural water flow and patrolled forests to prevent illegal logging. Importantly, participants are paid for this work, helping ensure long-term engagement.
Stipends earned through restoration activities are often pooled by community groups and reinvested into alternative livelihoods such as beekeeping, ecotourism and livestock rearing. These income streams help reduce pressure on mangrove forests once active planting slows down.
Science, monitoring and adaptation
Experts say one of the main advantages intermediaries bring is the ability to support adaptive management. Mangrove ecosystems are dynamic and highly sensitive to changes in water movement and salinity. When conditions shift, restoration plans must also change.
In Kenya, for example, monitoring revealed that some restoration sites suffered from stagnant water and high salinity. In response, additional funding was directed toward trench-digging to improve tidal exchange a step that significantly improved seedling survival.
Across its projects, Seatrees supports monitoring of seedling survival for at least two years after planting. Survival rates typically range between 50% and 80%, depending on site conditions. In the Florida Keys, where restoration is being carried out by a local NGO with volunteer support, survival has exceeded 80% at some sites.
Monitoring extends beyond trees. In advanced projects, partners track changes in biodiversity, fish populations, shoreline stability and community wellbeing. Making this data public, including challenges such as ongoing illegal logging, helps maintain transparency and adjust strategies over time.
More than planting trees
Scientists and conservationists increasingly warn against judging success solely by the number of trees planted. Mangrove restoration requires long-term stewardship, regular maintenance and strong local ownership.
Intermediary organisations are also investing in storytelling through photography and video to communicate why activities like monitoring, forest patrols and community engagement are just as important as planting seedlings. This approach helps attract sustained funding and public support, particularly from donors who may otherwise focus only on visible outcomes.
As climate risks intensify and coastal communities face rising seas and stronger storms, the pressure to restore mangroves will only grow. The emerging evidence suggests that restoration works best when local knowledge, scientific guidance and reliable funding are woven together with intermediaries quietly holding the threads.
The lesson from these projects is clear: saving mangroves is not just about putting trees in the ground, but about building systems that allow them, and the communities around them, to survive and thrive.