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

Shanjida Khan Shorna, Project Associate- Communication, Documentation and Reporting, LDD4IG, UNDP Bangladesh.

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

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

For nearly two decades, not a single sea turtle hatchling survived on the beaches of Saint Martin’s Island – Bangladesh’s only coral island. Once a thriving nursery for baby turtles, this tiny island saw its nesting populations plummet to zero amid coastal erosion, predators, unregulated tourism, and climate stress. Today, in a remarkable turn of events, over 3,000 baby turtles have safely scampered into the Bay of Bengal from Saint Martin’s shores, signaling a comeback for these gentle ocean wanderers. Behind this conservation triumph is a collaborative effort uniting the Department of Environment, the UNDP Accelerator Lab, and the island community itself – My Saint Martin’s. It’s a story of science and local stewardship coming together to restore a lost generation of sea turtles – and with them, new hope for the island’s marine ecosystem.

Background: Saint Martin’s Island and Its Marine Significance

Saint Martin's Island, Bangladesh's only coral-bearing island and an Ecologically Critical Area (ECA), is a small (\~8 km²), biodiverse marine hotspot south of Teknaf. Its clear waters host 66 coral species, 153 seaweeds, 240 fish, and 187 mollusks, with over 120 bird species, 29 reptiles, and 29 mammals documented. Crucially, the island's sandy beaches are a vital nesting site (November–March) for three globally threatened sea turtles: the Endangered Green Turtle (Chelonia mydas), Critically Endangered Hawksbill Turtle (Eretmochelys imbricata), and Vulnerable Olive Ridley (Lepidochelys olivacea). It is recognized as an "irreplaceable paradise" for coastal biodiversity.

Why Every Hatchling Counts: Sea Turtles and Ecosystem Health

Sea turtles are keystone species crucial for marine ecosystem health. Their ecological roles include:

1. Controlling jellyfish: Certain turtles eat jellyfish, preventing blooms that harm fish stocks, thus sustaining healthier fish stocks.
2. Grazing underwater vegetation: Green turtles graze seagrass, keeping meadows healthy as fish nurseries and aiding carbon storage. Hawksbill turtles clear sponges and algae from corals, supporting coral reef health.
3. Nutrient cycling: Nesting mothers bring ocean nutrients to the coast. Unhatched eggs and shells act as natural fertilizer for coastal vegetation, stabilizing shorelines. Turtles connect marine and terrestrial ecosystems.
4. “Cleaning crew”: Species like Loggerheads scavenge and break down matter (e.g., crustaceans), recycling nutrients on the ocean bottom and keeping the sea floor balanced.

With high hatchling mortality (perhaps 1 in 1,000 survive), every individual matters. Losing turtles would cause ripple effects, increased jellyfish, degraded reefs/seagrass, and broken nutrient cycles. Saving them is vital for protecting the entire marine ecosystem that supports countless species, including humans.

Troubled Shores: Threats to Turtles on Saint Martin’s

Despite its ecological importance, Saint Martin’s Island has been a challenging place for sea turtles to survive in recent decades. Multiple human-induced threats and environmental pressures had pushed the island’s turtle population to the brink:

Unplanned coastal development and heavy tourism, particularly due to resort lights and beach activity, are destroying prime sea turtle nesting sites on Saint Martin's Island. Lights disorient both nesting females and hatchlings, with observers noting "fewer mother turtles come ashore now" leading to failed nesting attempts.

The surge in stray dogs is devastating, with packs digging up eggs and attacking females. Local officers lament that "Turtles that come to lay eggs are dying every day after being attacked by dogs." Other predators like crows and jackals also raid nests.

Offshore, illegal monofilament gill nets ("current nets") are an invisible death trap, causing turtles to drown. Frustrated fishers often "intentionally cut turtle flippers or necks to protect their fishing nets" or beat entangled turtles to death, viewing them as a nuisance due to the lack of compensation for net damage. Hundreds of dead turtles wash ashore annually.

Plastic pollution, exacerbated by the island receiving "eight times more tourists than its capacity," is a major threat. Turtles mistake plastic bags for food, leading to gut blockage and starvation, and become entangled in "ghost nets."

Climate change presents new threats: hotter sands are skewing the sex ratio by producing more females (due to temperature-dependent sex determination), and stronger cyclones and sea level rise are washing away or flooding nests, killing embryos.

These combined challenges caused nesting activity to fall by "over 80%" in a decade, from 50–60 turtles annually to just 10–12 by 2022. Experts warned that Bangladesh was close to "losing its native sea turtle populations entirely," making conservation an urgent priority.

A Revival After Two Decades: Community Hatcheries Bring Back Hope

Facing a crisis, a 2021 initiative by the Department of Environment (DoE), with support from the UNDP Accelerator Lab funding, launched a community-based sea turtle conservation project on Saint Martin's Island. Implemented by Local Community with the technical support from AccLab and Environment Department and local youth, the strategy was to protect turtle nests and increase hatching success by relocating eggs to a safe hatchery, then releasing the hatchlings back to the wild.

Nightly patrols by DoE staff and trained local volunteers now secure nests from poachers, dogs, and tourists. The eggs are carefully excavated and reburied in a protected hatchery, a fenced and guarded plot managed by DoE and local community. This hatchery eliminates threats like predators and flooding by maintaining optimal conditions.

After 60–70 days of incubation, hatchlings emerge. They are briefly checked, then released in celebratory “hatchling release” events organized for the community. Under the supervision of DoE wildlife officers, the hatchlings are released on a quiet beach and allowed to scurry into the ocean, imprinting on their natal beach and offering a renewed hope for the species. As Ali Haider, Coordinator of the Amar Saint Martin initiative, noted, "It’s like sending our babies off to the ocean – we feel proud and hopeful."

Figure 1: Saint Martin’s Island, Bangladesh’s only coral island, provides vital nesting habitat for endangered sea turtles and supports rich marine biodiversity within its fragile coastal ecosystems.

The community-run sea turtle hatchery on Saint Martin's Island achieved major success in the 2024–25 nesting season, building on the previous year's efforts.

Hatchling releases began in February 2025. The season's first, 111 baby Olive Ridley turtles, were released on 28 February 2025, followed by several hundred more in early March, marking the first natural-born turtles on Saint Martin’s Island in roughly two decades. By mid-April 2025, 3,106 hatchlings had been successfully released into the Bay of Bengal, with the total over 3,000 by early April, a major conservation milestone.

This was the second consecutive successful year. In the 2023–24 season, the DoE and UNDP-supported team incubated about 3,184 eggs, releasing 1,246 baby turtles. The project showed that protected nests can achieve a hatchling rate of over 50%. Encouraged by this, the 2024–25 effort expanded, leading to thousands of releases.

Sea Turtles: Guardians of a Healthy Ocean

Sea turtles are vital for marine balance and have roamed oceans for over 100 million years, filling specific ecological niches.

On Saint Martin's Island:

• Olive Ridley turtles are omnivores, acting as "clean up" agents by eating invertebrates, which prevents prey species from overpopulating.

• Green turtles are herbivores, grazing on seagrass and seaweed. Their foraging maintains healthy seagrass beds, which are crucial nursery areas for fish and shrimp.

• Hawksbill turtles are spongivores that protect coral reefs by curbing sponges, which otherwise would smother the coral. This promotes reef health, shoreline protection, and tourism.

Turtles are also "ecosystem engineers" and "nutrient transporters." Nesting females bring marine nutrients (mineral-rich sand, protein-packed eggs) onto the beaches, feeding coastal ecology. Hatchlings feed other wildlife, and survivors continue the nutrient cycle elsewhere, connecting life from “plankton to predator” and securing a healthier ocean.

Beyond ecology, sea turtles hold cultural and ecotourism value as charismatic megafauna. Saint Martin's is developing a nascent eco-tourism interest around supervised hatchling releases and nesting tours. If managed carefully, this turtle-based tourism could provide sustainable income and educational opportunities for locals, with UNDP and partners developing the island as a turtle sanctuary.

Figure 2: Local youth volunteers on Saint Martin’s Island release Olive Ridley hatchlings from a community-managed hatchery.

People and Partnerships: The Power Behind Conservation

The Saint Martin's Island sea turtle revival is a success story built on the collaborative action of local people, government, and partner organizations, proving that protecting nature is everyone’s business.

The Department of Environment (DoE) provided the regulatory framework, declaring the island an Ecologically Critical Area and operating the hatchery with trained personnel. The United Nations Development Programme (UNDP), through its Accelerator Lab funding, offered resources and technical support. They helped design the community-based model, facilitated training for local youth, and provided essential equipment.

Crucially, community members have been a game-changer. The volunteer group “Amar Saint Martin” (My Saint Martin) comprises dozens of local youths who patrol beaches, guard nests, and rescue turtles, fostering a sense of ownership. Community awareness has increased, leading to more fishermen releasing turtles and understanding their ecological value. Islanders also successfully advocated for the enforcement of “low light zones” on nesting beaches.

However, the community stressed that compensation mechanisms or alternative livelihood support are needed to secure long-term fisher cooperation, a suggestion project partners are now exploring (e.g., net replacement support).

Employing local youth in conservation roles weaves conservation into the social fabric, creating ambassadors for the cause. This partnership model—involving the DoE, UNDP Accelerator Lab and local government—demonstrates that complex environmental problems can be solved when everyone works together. This community-led effort aligns with Bangladesh's commitment to UN Sustainable Development Goals like SDG 14: Life Below Water and SDG 13: Climate Action.

A Blue Future: From Saint Martin’s to the Bay of Bengal

The Saint Martin’s Island project offers a powerful message of hope for Bangladesh's sea turtles, which were recently nearing local extinction due to halted nesting and high mortality. This community-led effort proves that nature can recover with collective will, reawakening dormant beaches.

The return of thousands of hatchlings, a sight absent for a generation, highlights that the "ecologically critical area" status works when enforced and that conservation is vital for sustaining community natural resources. Each surviving turtle is a long-term investment, potentially returning to nest after decades, restoring the population, and securing the island's future as a vibrant ecosystem.

Challenges remain, requiring continued seasonal patrols, vigilance against threats like climate change necessitating sand temperature monitoring, and policy support like expanding marine protected areas and enforcing the use of Turtle Excluder Devices (TEDs). Success here is already inspiring replication across other coastal sites.

Saint Martin’s is a beacon on the Bay of Bengal, demonstrating that community-led conservation yields major results in terms of Behavioral Insights. As one local conservationist noted, "The story of Saint Martin’s is one of resilience — a reminder that nature heals when people care.” The waves carrying the hatchlings bear a powerful lesson: when science, policy, and community unite, endangered species are given a fighting chance, moving Bangladesh toward a bluer, more sustainable future.

📍 Saint Martin’s Island at a Glance: Location: Southernmost Bangladesh (Cox’s Bazar), 9 km south of Teknaf. Known for: Coral reefs, nesting sea turtles, rich marine life. Conservation Partners: Department of Environment (DoE), UNDP Bangladesh Accelerator Lab, local youth groups and communities. Total Eggs Protected (2024–25): 4,157. Total Hatchlings Released: 3,106 (and counting). Global Significance: One of the last turtle nesting grounds in Bangladesh, vital for Olive Ridley, Green, and Hawksbill turtles.