Technology and Community Restore Koh Phangan’s Marine Ecosystem

A new fight for Koh Phangan’s waters

Koh Phangan is famous for bright beaches and easy island life, yet its waters tell a tougher story. Years of drifting plastic and ghost fishing gear have scarred coral reefs and trapped marine animals that once flourished in the Gulf of Thailand. That toll drew scientist Tania Kanchanarak back to her birthplace. She co-founded the Aerial Recon and Recovery Initiative, known locally as ARRI, to remove hazardous ghost nets and debris using drones, artificial intelligence and a growing network of local volunteers.

Her team scans the sea surface from above, pinpoints likely debris in near real time, and plans retrieval dives when conditions are safe. The approach is precise and fast. After months of trial runs and model tuning, the group reports accurate mapping of debris fields, a key step that reduces wasted effort and improves safety for divers. In the past four months alone, ARRI and volunteers, many of them young islanders, have hauled more than three tonnes of waste from the Gulf. The work connects technology with community, and it gives those who depend on tourism and fishing a direct role in protecting the waters that support local livelihoods.

ARRI is part of a wider push to restore reefs and reduce waste across Thailand’s gulf islands. Koh Phangan’s neighbors, Koh Tao and Koh Samui, are developing coral nurseries, artificial reef projects, and citizen science programs. Government agencies and private partners are experimenting with large engineered reefs and deeper collaboration with coastal communities. Together, these efforts show how data, science, funding and grassroots energy can reinforce each other to heal damaged seas.

How the tech works

ARRI’s workflow combines drones, machine learning and ocean modeling to track and remove ghost gear. Drones fly low and slow over predefined grid patterns. High resolution cameras capture surface signatures and near surface shadows that may indicate nets, lines or plastic rafts. Back on shore, an AI model trained on thousands of labeled images flags likely debris and distinguishes it from seaweed lines, wave patterns and marine life. The system then projects likely drift paths using simulation models of wind and currents, which are influenced by tides and seasonal monsoon patterns in the Gulf of Thailand.

Drones and AI mapping

Artificial intelligence in this setting is a classification tool. It spots patterns and anomalies faster than manual review, and it does not tire. The model ingests visual cues, shape edges and color contrast to mark potential debris. The team validates those marks with targeted spot checks and updates the training set with correct labels, which steadily improves accuracy. This tight loop between fieldwork and data helps the system adapt to changing light and water conditions.

From map to recovery

Once debris hotspots are verified, ARRI organizes retrieval missions with trained divers and boat crews. Divers cut nets away from coral heads with care to avoid further damage. Rope sections are bundled and lifted to boats in stages to prevent sudden surges that can harm reefs. Safety protocols consider surge, visibility and entanglement risk. The recovered material is sorted on land for recycling or repurposing. Each removal is recorded, so the team can study repeat hotspots and refine current models for future patrols.

Ghost gear, a silent threat

Ghost gear refers to nets, lines and traps that are lost or discarded at sea. These materials can drift for years. They entangle fish, sea turtles and dolphins, smother coral, and break fragile reef structures. As fibers degrade, they shed microplastics that enter the food web. In tourist areas like Koh Phangan, ghost gear also threatens the draw that keeps local businesses alive. Removing it reduces direct harm to wildlife and eases pressure on reefs already stressed by warmer seas and coastal development.

ARRI and its partners focus on ghost gear because rapid retrieval prevents repeated damage from a single net. The group’s six month collaboration with a major seafood producer covers a 12 square kilometer survey zone around Koh Phangan. The aim is to collect and sort debris, recycle usable material and route it into a circular economy, with a target of more than 3.2 tonnes removed in the campaign window. Tactical mapping means teams can plan the safest, most efficient route to pull nets before they drift into deeper or more delicate habitats.

Ghost gear removal complements other reef care activities. Divers in the Gulf of Thailand run regular underwater cleanups, remove invasive algae that overgrow stressed coral, and stabilize broken reef structures. Where branching corals have snapped in storms, conservation teams use fragments of opportunity, small pieces that can be regrown in nurseries and then replanted. These measures are not a cure, but they can speed local recovery when water quality and temperature are within safe ranges.

Funding and partnerships

The ARRI project gained speed with new backing from Thai Union Group. The partnership supports equipment, boat time and local hires, and it integrates debris recovery with recycling pilots so waste is kept in the value chain rather than sent to landfill. The sponsor describes the approach as a practical model to tackle marine pollution at source while creating local jobs in surveying, safe retrieval and materials processing.

Private support is part of a broader pattern in Thailand. Conservation groups often rely on a mix of government oversight, tourism revenue and corporate funding to operate at scale. That mix helps small teams test new tools like AI mapping while keeping their focus on hands-on work at sea. The combination of technical know-how, logistics, and community trust is essential in places where fishing, tourism and conservation must align to succeed.

Turning waste into value

On Koh Samui, a volunteer network known as E2C works with ARRI to give non recyclable debris a second life in construction. Engineers and builders there have shown that mixing chopped net fibers into concrete can increase tensile strength and flex tolerance. The result is a tougher brick that resists cracking, especially useful in coastal settings where salt and humidity stress materials.

The team produces about one hundred bricks a day, using more than seven hundred and twenty kilograms of recovered nets and plastic so far. Each mold is a teaching tool for students and residents who see that waste can be a resource. Schools and local shops display the bricks and explain the process to visitors. The message is simple. Pull the nets from the water, keep plastics out of the landfill stream, and make useful products that serve the community.

Building a recycling backbone

In Krabi, the Second Life initiative led by Wongpanit Krabi Co Ltd is building a more complete system for waste collection and processing. The program, which works with more than twenty thousand families, teaches sorting at the household level, sets up reliable collection and routes low value plastic to facilities that can process it. The effort reduces the need to ship waste to Bangkok, cuts disposal costs and keeps plastic out of waterways where it can drift toward sensitive reefs.

The system has certification under an international standard known as VERA. It also emphasizes prevention. Reducing non decomposable materials like PVC at the source shrinks the stream of waste that might reach the sea. When households and businesses are part of that solution, clean seas become a shared outcome, not a burden placed solely on divers and conservation groups.

Artificial reefs and science in the Gulf

Beyond cleanups and recycling, Thailand is trialing large engineered reef structures. Near Koh Phangan, the Department of Marine and Coastal Resources worked with partners to relocate seven retired offshore platform jackets to a protected site. The project, completed in 2020, created a field of steel frames placed at depths of about thirty eight to forty meters with at least fifteen meters of clearance below the surface for navigation safety. The artificial reef area covers four square kilometers, with the jackets themselves covering a much smaller footprint.

These structures provide vertical relief and hard surfaces for corals and invertebrates to settle. Early studies on jacket structures in the Gulf of Thailand suggest they can host diverse fish communities and relieve pressure on natural reefs by drawing divers to deep water sites. Agencies continue to monitor the site to understand how currents, sediment and species interactions shape growth over time.

Artificial reefs are a tool, not a replacement for natural systems. Research on restoration points to both promise and limits. Techniques like coral microfragmentation, nursery growth and mineral accretion can boost local cover, yet survival depends on local conditions. Heat stress, sedimentation and poor water quality can overwhelm even well designed projects. That is why many Thai programs combine artificial structures, careful transplantation and water quality measures with enforcement of protected zones.

Lessons from Koh Tao’s conservation surge

Koh Tao, just north of Koh Phangan, offers a high energy case study in community driven conservation. Dive schools there have built programs that train visitors to conduct reef surveys, remove debris and restore corals. Conservation certifications are rising among divers as reef bleaching events expand worldwide. Citizen scientists now identify coral types, record color changes that indicate stress and log fish populations that respond to reef health. Data feeds into global projects and informs local management.

Local groups maintain artificial reef sites and coral nurseries and run regular cleanups. One technology used on Koh Tao is often called mineral accretion. It sends a low voltage current through steel frames underwater. The current encourages minerals in seawater to crystallize on the frame, creating a more favorable surface for coral fragments to attach and grow. Results vary by site and conditions, yet in some locations this method supports faster early growth, especially for branching species used in many restoration programs.

Policy and finance have also evolved. Koh Tao introduced a small tourist user charge of twenty baht per visitor with legal backing to ensure funds flow to waste management, conservation and public services. Community groups and businesses promote reef safe sunscreen and support rules that limit boat traffic over shallow coral. Recycling ventures on the island turn plastic waste into useful products, which helps keep beaches and dive sites clean during busy seasons. These steps show how tourism and conservation can coexist when rules are clear and revenue supports the commons.

Can AI speed up reef recovery

Artificial intelligence is moving from lab to waterline in reef science. One recent study trained deep learning models to classify reef condition across more than twenty thousand underwater images from the Indo Pacific. An ensemble of advanced architectures outperformed single models, reaching a strong micro F1 score while labeling signs like disease, predation, competition and rubble. Automated classification helps teams process image backlogs faster and track changes with more consistency than manual reviews alone.

On the islands, AI shows up in several forms. ARRI uses it to detect likely ghost gear from drone imagery. Citizen scientists train algorithms to identify fish in survey videos so biologists can measure reef health without hours of manual review. Managers can then direct divers to the most threatened sites or identify recovery zones where protection is working. The technology does not replace field skills, it supports them. That pairing is visible every time volunteers turn model output into a safe, efficient recovery mission on the water.

What visitors and residents can do now

Practical steps matter. Visitors can choose dive operators that support reef monitoring and debris removal, follow buoyancy and finning guidance to avoid contact with coral, and use reef safe sunscreen. Respect no boat zones and temporary closures that give stressed reefs a chance to recover. Avoid feeding fish and keep plastics out of the sea by carrying a refillable bottle and reusable bag.

Residents and businesses can strengthen sorting at the source, support local recycling partners and join monthly cleanups. Fishers can report nets lost at sea and mark locations for retrieval crews. Schools can teach students how reefs support coastal protection and food security. Each action supports the larger network of projects that are beginning to show results across the gulf islands.

What to Know

• ARRI on Koh Phangan uses drones, AI and current models to locate ghost gear and plan safe retrieval dives.
• Volunteers and staff have removed more than three tonnes of marine waste in recent months across the Gulf of Thailand.
• A six month partnership supports a 12 square kilometer survey zone and targets removal of more than 3.2 tonnes of debris.
• On Koh Samui, recovered nets are mixed into concrete to produce stronger bricks, with about one hundred bricks made daily.
• In Krabi, a certified recycling program works with over twenty thousand families and focuses on prevention and sorting at the source.
• Thailand’s first rigs to reefs project near Koh Phangan placed seven retired platform jackets as protected artificial reefs at depths near forty meters.
• Koh Tao trains divers in citizen science, runs coral nurseries and promotes reef safe sunscreen, supported by a small tourist user charge.
• AI tools now help classify reef condition at scale and speed up monitoring, allowing faster response to stress and damage.