NEGROS OCCIDENTAL, Philippines — As a boy growing up in Cauayan, Negros Occidental, Reilan Guanzon remembered fishing with his father in waters teeming with life. Clusters of surgeonfish and parrotfish were so abundant that they turned the shallow waters dark.

“But when I dove in the ocean, it was even more beautiful. The corals, big and small with varying shapes, were screaming in color,” Guanzon, 38, said. 

Back then, his fishing area thrived near Danjugan Island Marine Reserve and Sanctuaries, a Marine Protected Area (MPA) home to 572 marine fish species and 244 hard coral species.

Beyond Danjugan, many areas around Negros Occidental were once known for their rich fish populations and vibrant coral reefs. However, this is no longer the case in 2024. 

“Now when you dive in those same areas, there would almost be no fish. We used to have catches that were one meter long, but now, the fishes you would see are very small,” he said.

Guanzon, a fisherman for over 20 years, attributes the decline in fish catch to a combination of climate change and overfishing.

Plight of Cauayan fishers

Reilan Guanzon demonstrates the size of their catches when he was younger. (Rainielle Kyle Guison)

“Overfishing is an issue that many know, but there are fisherfolk who do not realize that the decline in our fish catch is also an outcome of climate change,” said Guanzon.

The Danjugan Island and its MPA, managed by the Philippine Reef and Rainforest Conservation Foundation, Inc. (PRRCFI), is not immune to the impacts of global warming such as typhoons and coral bleaching, or when corals lose their colors and turn white. 

In recent months, Guanzon and his fellow fishermen have noticed patches of ghost-white coral already neglected by the fish that used to take shelter in them.

“The coral reefs here in Danjugan are very important because all the fishes we catch will be gone if the corals are gone. It’s their source of shelter and food, and it’s where they lay their eggs. It’s where all our stocks come from,” he added.

Because coral reefs support 25% of all marine life, a decrease in fish population will inevitably affect the livelihood of local fisherfolk.

Christopher Gamao, a 42-year-old fisherman, echoed Guanzon’s concern that fishing has become increasingly difficult in recent years. At times, they return empty-handed, especially after typhoons.

Gamao recalled the devastation of Super Typhoon Odette (Rai) as the strongest cyclone their town had ever faced. Two months after Odette hit the Philippines in December 2021, Cauayan’s fishing community continued to struggle as destroyed coral reefs hampered fish populations from recovering.

A father of two, Gamao had to find various other jobs when he wasn’t earning enough from fishing.

To support fisherfolk like him, the PRRCFI offers alternative livelihoods  such as farming mud crabs, raising pigs, weaving pandanus palms, and producing banana chips, among others.

According to Gamao, his job as a fisherman and his wife’s side hustles earn them a total of P10,000 per month, which according to him is barely enough for them to live comfortably.

In times of typhoons, these additional streams of income are interrupted, leaving fisherfolk like Gamao and Guanzon to find any job available to feed their families.

 “The weather has become so unpredictable now. We can’t fish when it’s too windy and the waves are big, and we can’t farm when typhoons destroy our coops and gardens. When it’s too hot, there would be nothing to catch. It’s a very difficult situation here for us,” Gamao said.

Climate change: Reefs’ ‘biggest enemy’ 

The Philippines, located in the Coral Triangle, is home to numerous coral reefs that were significantly impacted by the most recent global coral bleaching event. (Map from the Philippine Coral Bleaching Watch.)

Early in 2025, the World Meteorological Organization confirmed the 1.5°C breach of the global average temperature threshold set by the Paris Agreement, an international climate treaty. This officially marks 2024 as the warmest year on record, reaching an average temperature of 1.55°C.

To most people, this signals hotter weather, but to Guanzon and Gamao, this means fewer catches and worsening bleaching events.

The National Oceanic and Atmospheric Administration’s (NOAA) Coral Reef Watch, a key institute studying coral health, announced in April 2024 the fourth and worst global mass coral bleaching event in history.

A reef survey done in Danjugan in June 2024 exhibited that its coral reefs have suffered from bleaching. While the area is abundant in live corals, many of them, especially in the shallow areas, already seem lifeless without their color.

“The most affected corals are the ones closer to the shore. When bleached, corals weaken, and when typhoons come, they are destroyed and turned into rubble,” said Georgivic Cruz, a field biologist of PRRCFI.

“But, going deeper into our reefs, the corals are in a better state. We have seen bleaching in the deeper areas but not quite as much in the shallow areas,” she added.

According to Cruz, shallow waters heat up more quickly under the sun, making temperature increases a significant cause of bleaching in corals near the shore. On the other hand, corals in  deeper areas are in a better state as water temperatures are more stable there.

Since early 2023, mass bleaching events have been confirmed in many countries, which on record amounted to 77% of the world’s reef areas.

Other greatly affected regions include the Great Barrier Reef in Australia and reefs in the Coral Triangle. This marine biodiversity hotspot, home to 75% of all known coral species in the world, includes reefs in the Philippines.

“Apart from being considered the rainforests of the sea as they have a role in getting carbon out of the air, coral reefs also provide shelter, food, and nutrients for marine life. In our town where the economy is mainly dependent on fishing, the coral reefs are very important. With that, you can really say that global warming and all this is affecting us here,” Cruz explained.

Can coral reefs survive climate change?

Dr. Rene Abesamis conducted an inception workshop with the project’s partner LGUs and community members in Negros Occidental. (Rainielle Kyle Guison)

Since the effects of global warming are mostly irreversible, many marine life initiatives focus on protection and conservation.

One such initiative is led by coral reef ecologist Rene Abesmis, who was named one of the six Pew Marine Conservation Fellows for 2024 by The Pew Charitable Trusts. He was awarded $150,000 to conduct a three-year project identifying climate-resilient coral reefs and establishing their protection. 

“Several studies show that there are parts of the ocean where coral reefs seem to decline slower and recover quicker. These areas are called climate refugia, which could possibly have climate-resilient coral reefs,” Abesamis explained.

Local scientists and community members such as Cruz, Guanzon, and Gamao will assist in the project, which began in July last year. Aside from being regular fishermen, Guanzon and Gamao are deputized bantay-dagat, tasked to safeguard marine ecosystems from illegal fishing activities. They were also trained for marine environment conservation and preservation.

“The research should also benefit the communities. Therefore, one way to help ensure this is to try to involve them meaningfully in different parts of the research process: at the beginning when the need for research is explained; during data collection and interpretation; and when the results become available for informing policies or decisions,” said Abesamis.

While these citizen scientists do get additional compensation for being a partner in the project, they see this as a force for good that will eventually benefit them in the future.

Replicating strategies

Danjugan’s divers remove algae from the already bleached coral table. (Philippine Reef and Rainforest Conservation Foundation, Inc.)

The Danjugan Marine Reserve and Sanctuaries has been in conservation for 30 years and its successful development of protected areas has inspired nearby communities to develop their own voluntary fish sanctuaries such as in the town of Elihan in Cauayan.

Abesamis hopes his project will help prescribe better protection and policies for more areas. 

“His project will definitely be helpful in identifying which marine areas need better or more protection and we will know if there are species or families, or coral forms that are more resilient to heat. I think that the information this research will yield will be useful in coral reforestation,” Cruz said.

Some marine scientists in Danjugan previously tried coral replanting in the MPA more than two decades ago. However, this effort failed to work due to coral bleaching, species mismatch, and typhoons.

“At first, it seemed like it worked because we saw some growth, but they eventually died. It’s a trial-and-error process and it was expensive, so the marine science community decided to promote better protection rather than investing in coral rehabilitation,” said Terence Dacles, one of the marine biologists who worked on this project and a founding member of the PRRCFI,

One potential outcome of the Pew project is identifying heat-resilient reefs that could be designated as new MPAs.

In the future, scientists and community members alike hope that this project will be an example of a practice in coral reef management and conservation.

“I don’t see it as a blueprint for global coral protection—that seems too ambitious. At best, maybe an example that we could learn from to inform Philippine policy and one that could be relevant to Southeast Asia,” Abesamis said.

With climate bleaching affecting many parts of the planet, the identification of climate refugia can be an initial step to combat other ocean-related effects of climate change in the future.

“In my experience of being a bantay-dagat for over 10 years, I’ve come to believe that conservation is the most sustainable solution that will keep our seas thriving even in the next decades. It has become my passion and it warms my heart that I get to be part of purposeful initiatives like this,” Guanzon shared.