SSI x Edges of Earth: Belize FIghts to Save Reefs from SCTLD

March 20, 2025

As our expedition team navigated through Caribbean countries, we could not escape a malicious scourge plaguing every dive site we visited: stony coral tissue loss disease (SCTLD).  Every scientific team we met, every researcher we encountered, and every diver we partnered with had it on their minds. The impact on coral reefs was so devastating that it left some team members in tears after surfacing. It was heartbreaking to imagine what these vibrant underwater ecosystems once looked like before the catastrophic wipeout.

When you journey to these renowned dive spots in the Caribbean, your goal is to witness thriving ecosystems that have been celebrated since scuba diving became popular in the 1950s and 60s. Sadly, in many of these iconic locations, that vision is currently out of reach. Numerous reef systems have suffered greatly due to climate change, human activities, and more recently, the devastating effects of the aforementioned disease. 

SCTLD could best be described as "underwater Covid-19," and is considered the deadliest disease outbreak in coral history. This devastating occurrence began making headlines as the global pandemic was wreaking havoc in 2019/2020, though its first sightings were reported in Florida in 2014. Affecting 20 different species of coral, SCTLD has now spread to 18 countries worldwide, including the beloved dive mecca, Belize.

All Hope is Not Lost – Tackling STCLD in Belize

Flash forward to May 2024, and we were speeding across the water on a boat bound for Turneffe Atoll, the largest atoll in Belize. The journey took us through mangrove channels, with perfectly still, turquoise water surrounding us, and not another boat in sight. Our mission was to meet the team assessing the extent of the damage SCTLD had wrought on these once-healthy reefs; the team that was tirelessly committed to combating this devastation through their research and management work.

After a 1.5-hour boat ride, we arrived on the southeastern side of Turneffe Atoll at Calabash Caye Field Station, 53 kilometers (33 miles) east of mainland Belize. This is where we were living alongside the dedicated team from the University of Belize Environmental Research Institute (UB-ERI)  who use this location as their research base. Despite their best efforts, managing the disease presents a monumental challenge due to its extensive impact and the difficulty in controlling its spread. 

Dive professionals, guides, and scientific teams have been deployed all over the Caribbean to manually administer treatments that can halt the disease. However, the vast expanse of affected reef systems and the intensive manual labor required make it extremely difficult to address the widespread damage in a scalable way. For our upcoming dives off of Calabash, the scientific team we were shadowing was going to show us why this was such a complicated situation based on the treatment plan they had in place.

Leading us was Galento Galvez, a dedicated scientist with a long history with Turneffe. For Galento, the concept of "home" is intrinsically tied to the islands, despite originally hailing from San Ignacio, located inland. Having called the atoll his playground for the past 27 years, Galento’s emotive experiences have deeply influenced his career path. Witnessing significant changes in the marine environment over his lifetime, Galento has seen the once vibrant reefs—thriving with sea cucumbers, conchs, and sea urchins—transform drastically. These vivid childhood memories now stand in stark contrast to the depleted numbers found today, which was clearly a heavy topic for him. 

Galento, other members of the UB-ERI team, and Josh Borland—the Field Station Manager and certified dive instructor—took us out to sea to demonstrate their SCTLD treatment plan. Galento explained that Turneffe Atoll is one of the country’s hardest-hit areas, with severely damaged coral cover. This year, they are conducting a comprehensive survey with partners Turneffe Atoll Sustainability Association (TASA), revisiting sites to quantify the damage and compare it with ten years of data. 

As we navigated some of the more renowned dive sites, Galento told us, "The disease has passed through Turneffe, leaving a lasting impact. Despite our efforts, this treatment is manual, labor-intensive, and unfortunately, not scalable." The team’s 2024 initiative focuses on extensive data collection to grasp the full extent of SCTLD and to devise more effective strategies for coral recovery and conservation.

RELATED: SSI x Edges of Earth: Tackling The Coral Crisis at Roatan Marine Park

Taking our first plunge into the waters of Turneffe, it was initially challenging to identify the impacted coral. To the untrained eye, the signs of disease are not immediately apparent. However, once you understand what to look for, the entire reef’s condition becomes unmistakably clear, revealing the extensive spread of this deadly disease. 

Galento and his scientific partner, Bonnie Young, meticulously selected which corals to treat, constrained by the limited resources they could carry in their bags of syringes. These syringes, filled with antibiotics, deliver a paste-like substance to the lesions on the corals. This treatment helps prevent the ongoing spread, allowing the corals to reproduce, though it should not be mistaken as a cure.

Because SCTLD is affecting reefs across the Caribbean, UB-ERI has the opportunity to collaborate with research teams from other regions, facing similar issues. However, the specific challenges at Turneffe require the dedicated efforts of its people who possess unparalleled knowledge of their local environment. These experts are working alongside diverse teams from science, tourism, conservation, government, and business sectors to address the crisis. Despite local affliction in the Caribbean, the implications are global. 

Reefs are crucial natural structures, producing half the ocean’s oxygen and supporting marine species vital for human survival. Without these ecosystems, the repercussions would be felt worldwide.

UB-ERI and their collaborators are addressing both the immediate impacts of SCTLD and broader initiatives to better understand, manage, and conserve their reef ecosystems. For example, UB-ERI is conducting research into the genetic structures and population dynamics of marine species at Turneffe. This study aims to reveal how marine populations are interconnected across Belize’s waters, providing a clearer picture of species distribution and movement. 

By understanding genetic connectivity, fisheries managers can gain critical insights into migration patterns and breeding behaviors, supporting the development of targeted conservation strategies that promote the long-term health and sustainability of marine ecosystems.

And that is not all. The team is tackling a significant knowledge gap in marine systems by exploring coral spawning and possible restoration initiatives as well. By monitoring coral spawning events and understanding their behavior, UB-ERI plans to lay the groundwork for more effective restoration strategies. By investigating the timing and methods of coral spawning, ERI aims to build a comprehensive understanding of coral ecosystems, which is vital for informing and improving restoration initiatives. 

RELATED: Great Barrier Reef Foundation Brings Hope for World’s Reefs

Then there is the Resilient Reef Initiative, powered by the Great Barrier Reef Foundation, which UB-ERI is actively involved with. This project emphasizes stakeholder engagement in marine conservation, bringing together frontline stakeholders such as fishermen, Divemasters, and resort operators, to provide valuable observations about changes in the marine environment, informing broader conservation strategies beyond just mitigating diseases like SCTLD. While challenging, this has been generating some real excitement for its potential impact in better understanding the ocean landscape at Turneffe.

The aim is to integrate these community members into the conservation process to better tackle the coral crisis. This involves determining whether the training provided will enable stakeholders to apply treatments directly or simply identify, monitor, and notify UB-ERI for further action. This pilot project was launched before SCTLD spread to other parts of the country, aligning with one of RRI’s flagship actions: "Strengthen coral reef resilience through science for adaptive management and stakeholder engagement to respond to long-term threats."

The hope is that the methods developed in Turneffe can be used throughout Belize, promoting a nationwide approach to coral reef resilience.

Amidst the challenges, Galento kept reminding us that all hope is not lost. Some passionate young individuals are now asking the bigger questions about the ocean. At UB-ERI in particular, as well as other NGOs, there is a noticeable increase in interest in marine conservation. 

"It breaks my heart to see this once-vibrant reef in such a state, but we are starting to build the capacity to face these new challenges. This is good news. We have not given up; we have not turned a blind eye. We are tackling it head-on. There is so much more to do and so much more to learn. As a Belizean collective, we are really standing up and owning this. We are going to make progress."

The government has taken significant initiatives in marine conservation, collaborating with numerous organizations driven by the cultural identity of Belize. 

This deep-rooted connection to the ocean has made marine science and conservation a country-wide movement. One that resonates with just about everyone. "Belizeans take immense pride in their culture, including their music, food, and history. Originating from a background of fishermen and farmers, and with a history of slavery, Belizeans have developed a profound bond with nature. One that no coral disease will break," Galento shared as we made our way back to the field station after a hard day of diving. 

This passion and cultural identity have inspired a wide-reaching vision, uniting the community to see the bigger picture and work together towards preserving their natural heritage in the face of the climate crisis. Living at the field station and witnessing first-hand the love for their home, it was not grief for the declining reefs of Turneffe that lingered in our minds as we made our way back to the mainland. 

This is one of the best examples of people of all different skills and backgrounds coming together to tackle something massive head-on.

They are tackling this even though the work is hard, grueling, and at times emotionally painful. Today, the UB-ERI team and the Calabash Caye Field Station do not have all the answers. But what they do have is an unbreakable and distinctly "Belizean" spirit, which means they are destined to get many steps closer to finding scalable solutions.

Feeling inspired? Get involved and help protect our oceans by joining SSI’s new ‘Coral Reef Conservation’ and ‘Invasive Species Management’ specialties. Launched as part of the Blue Oceans initiative, these specialties empower you to contribute to marine conservation.

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Andi Cross is an SSI Ambassador and lead of the Edges of Earth expedition, highlighting stories of positive ocean progress and how to explore the world more consciously. To keep up with the expedition, follow the team on Instagram, LinkedIn, TikTok, YouTube, and their website.