By Ramiz Uddin, PhD; Head of Experimentation, UNDP Accelerator Lab Bangladesh

Osama Bin Tahir, Applied Statistics and Data Science, University of Dhaka

Mejanur Rahman, Applied Statistics and Data Science, University of Dhaka

Saint Martin’s Island, Bangladesh’s only coral island, sits at the nation’s southernmost tip – a small (8 km²) but biodiverse community confronting the frontlines of climate change. Buffeted by rising seas, cyclonic storm surges, and erosion, the island has historically relied on natural green barriers for protection. Chief among these are the dense thickets of Keya (screwpine) that once ringed the island’s beaches, anchoring sand dunes and deflecting waves. Over the past decade, however, this natural defense has been decimated by unplanned development, shrinking from roughly 20 km of the Keya forest to only 8 km by 2023. Hotels and resorts have cleared vast swathes of Keya for construction, leaving the coast exposed; locals report that tidal surges now penetrate farther inland, damaging trees and homes more than ever before. Environmental experts warn that the island’s ecology faces severe damage if the remaining Keya forests are lost, as these hardy shrubs serve as critical buffers during cyclones and high tides.

In response to these threats, UNDP Accelerator Lab and its partners have championed an integrated, community-centered approach to bolster coastal resilience on Saint Martin’s. A cornerstone of this effort has been coastal tree plantation – the establishment of protective greenbelts of Keya and other species along vulnerable shorelines. This blog outlines how, over 2023–2025, UNDP’s Accelerator Lab, together with the Government of Bangladesh and local stakeholders, implemented extensive tree planting initiatives on the island, and highlights the community feedback, challenges, and lessons that emerged. It draws on focus group discussions with residents and local leaders, as well as on-the-ground project data and broader best practices in coastal ecosystem management.

A Community Embraces Coastal Tree Planting

Figure 1: Community members, youth, and local stakeholders participate in coastal tree plantation activities on Saint Martin’s Island, strengthening natural defenses and promoting community-led climate resilience.

From fishermen and boatmen to shopkeepers and elders, community members universally praised the new tree plantations during focus group discussions in 2024–2025. To islanders, the value of planting Keya and other coastal trees was not abstract – it was tangible and even existential. Residents repeatedly referred to the trees as “protective infrastructure” vital to the island’s survival. “These trees were planted to protect the island. They are saving us, and planting more would be even better,” said one small business owner, capturing a common sentiment. Another community elder explained that coastal trees shield important local sites – “The Keya trees are very good for the island. They help our graveyard area and the coast.” Indeed, the islanders view tree planting not just as an environmental activity but as an investment in the long-term safety of homes, roads, and cultural landmarks along the shore.

This strong local buy-in reflects a keen awareness of the island’s fragility and the protective value of nature. Scientific studies affirm what Saint Martin’s residents intuitively know: healthy coastal vegetation can significantly dissipate wave energy and reduce storm surge heights before they reach communities. Pandanus (Keya) shrubs, in particular, have evolved to thrive in harsh maritime conditions – their stilt-like roots lock into sandy soil, and thick bushy growth breaks the force of onrushing water. It is therefore heartening that local people see these plantations as “essential to the island’s survival,” not merely as greenery. Community members across all nine villages expressed a strong desire for more trees, especially along exposed beaches where wave erosion is eating away at land. As one bike driver put it, “Planting more [trees] would be even better.” Such community enthusiasm is a critical asset – it signals grassroots legitimacy for nature-based solutions and creates a social foundation on which future climate resilience efforts can build.

Scaling Up Greenbelts: From Pilot to Island-Wide Coverage

What began in mid-2023 as a pilot Tree Plantation Inauguration Programme has since expanded into a broader island-wide greening effort. The inaugural campaign – organized by UNDP Accelerator Lab in partnership with the Ministry of Environment, Forest and Climate Change, Department of Environment (DoE), Department of Forest (DoF), Tour Operators Association of Bangladesh (TOAB), Tour Operator Owners Association of Cox's Bazar (TOAC), Bangladesh Tourism Board, and local authorities – was a one-day high-visibility event designed to galvanize public support. On July 5, 2023 (tentative), over 100 participants, including students, youth leaders, fishermen, tourist guides, and local officials, joined a rally from Gabibar Shop to Winter Spring Beach Resort, converging to plant the first 100 Keya saplings near the shoreline. This symbolic planting was accompanied by an awareness discussion at the cyclone shelter, underscoring the importance of coastal forests for the island’s future. The event’s chief guest from the Ministry of Environment and the Teknaf Upazila Administration lauded the youth-led initiative, while community leaders pledged their cooperation in nurturing the seedlings. (This kick-off was part of “Plan A” for the programme, which also envisioned a human chain at Jetty Ghat for tourist awareness, pending logistical feasibility.)

Following the inauguration, the project rapidly scaled up planting across multiple sites. By early 2024, roughly 37,000 Keora (Keya) seedlings had been planted along the island’s most erosion-prone coasts, including the Marine Park on the west, the north and south sides of Jetty Ghat, beach strips near resorts (Prasad Paradise, Fantasy, Blue Marine), and both the eastern and western shores of Kona Para. An additional 2,150 mangrove saplings (of species like Keora and Golpata) were planted along an inner tidal creek from Fakirapul to Kona Para, aimed at restoring a fringe of mangroves that historically existed decades ago. “We are trying to cover from the jetty to Coral View, all vulnerable spots,” noted a Department of Forest official involved. UNDP Accelerator Lab and the Saint Martin’s Union Parishad jointly identified 14 priority locations, with a long-term vision of planting up to 200,000 seedlings (including Keya, Nishinda, Sagarlata vines, and coconut palms) by the end of 2023. While not all of these were achieved within the year, the groundwork has been laid – literally – for an island-wide green shield. Each planting site was selected in consultation with locals, ensuring that species chosen (e.g., Keya and salt-tolerant shrubs) were well-adapted and welcomed by the community.

Multi-stakeholder partnerships have been key to this scale-up. The project actively involved agencies like the Department of Forests, the Ministry of Civil Aviation and Tourism, Cox’s Bazar District Administration, and NGOs, alongside UNDP Accelerator Lab. 

Early Results: High Survival but Maintenance Gaps

One year after implementation, community feedback suggests that the coastal tree plantation on Saint Martin’s Island has achieved encouraging early results, alongside emerging challenges. Focus group participants estimated that around 80 per cent of the saplings planted in 2024 remain alive, reflecting appropriate species selection, sound site choice, and favorable growing conditions. In several areas, young Keya plants have already reached waist height, forming new green belts along previously bare beaches. Local residents expressed pride in these visible changes, noting that the trees are already helping to reduce the impacts of waves, storms, and erosion.