Pioneering Scuba Diving Survey of Uson Marine Sanctuary, Caibiran, Biliran

On March 29, 2025, just a day after my mother's birthday celebration in our hometown of Biliran, we set out on a mission that combined both passion and purpose—an exploratory dive into the oldest marine sanctuary in Biliran, located in the municipality of Caibiran.

I had informed Melo, the owner of the only dive shop in Biliran, that we will be going home on the last weekend of March. Despite originally setting his sights on Dalutan Island, Melo changed course with contagious excitement—he wanted to bring us to Uson Marine Sanctuary, which was established over two decades ago but was long forgotten and rarely visited.

Early Morning Preparations

We met Melo at Agta at exactly 7:00 AM. While waiting for his nanny to arrive so he could leave, our dive team (composed of Sugbudiver members - Vard and Ikuo, along with dive instructor Melo and dive guide Marvel) ensured all tanks and gear were ready and loaded into Melo’s van. I did a final check of our regulators—everything was good to go.

At 7:27 AM sharp, our van departed, winding through 42 kilometers of Biliran’s rolling hills and quiet towns until we reached Canaan Hill Farms in Caibiran at 8:47 AM. The sky turned from overcast to rain as we arrived, raising concerns about visibility underwater.

Meet & Greet with Local Stakeholders

Upon arrival, we were warmly greeted by the Espinazo family, the owners of Canaan Hill Farms, a representative from the Department of Tourism in Caibiran, and some local officials. They expressed their hope that our dive would provide insights into the current condition of their sanctuary. From there, we made our way to Barangay Uson, logged in at the barangay hall, and proceeded to the shoreline to board our boat.

To our surprise, two locals from the Barangay, Jemmel Espinazo and Jansen in full gear were already on site and announced they would be joining us. Melo told us they were uncertified and had only bought gears from his friend. That alone raised red flags—but we stayed open and cautious.

First Dive – A Silty Introduction

Dive 1: 9:51 AM

• Max Depth: 19.7 meters

• Average Depth: 12.9 meters

• Dive Time: 42.54 minutes

• Visibility: Less than 3 meters

We began with a prayer lead by Priscilla Espinazo, asking for safety and clarity on this cloudy day. As we descended, it became clear that the sanctuary had seen better days. The bottom was mostly silty, with scattered patches of hard coral—many of them covered by layers of sediment. Coral species like barrel, brain, and table corals were present but heavily stressed.

Fish life was sparse—just a few angel fish, rabbitfish, and anemonefish. Still, a moment of magic came when a large green sea turtle, around two feet in length, glided out from the coral. I approached to photograph it, but it swiftly swam away the moment it noticed all five of us converging around it—a reminder that even the gentlest giants know when to make a quick exit.

Just when we were getting into the groove, our dive was cut short. The Jemmel's tank was nearly empty, and given that he lacked basic buoyancy control and didn’t even know how to inflate his BCD, we made the collective decision to end the dive early and ascend with him.

Back on land, the locals where wondering why the dive ended so soon. We explained that safety must always come first. During our surface interval, we had coffee and biscuits at the barangay hall—the only source of hot water nearby.

Second Dive – Into the Abyss

Dive 2: 11:59 AM

• Max Depth: 29.4 meters

• Average Depth: 18.3 meters

• Dive Time: 27 minutes

For our second dive, the local fishermen guided us to a deeper part of the sanctuary. They mentioned seeing a barracuda and even a shark in the area. Following a descent line, we dropped into darkness—so much so that even at noon, dive lights were essential.

At 27 meters, I finally spotted the sandy bottom. Huge Spanish mackerels (tanguigue) swam curiously close. With our No Deco time quickly ticking down, I took a few top-down photos to minimize nitrogen build-up and began our slow ascent.

The Jemmel and Jansen struggled with buoyancy — bouncing in the water column, burning through their air quickly. We cut the dive short at just 27 minutes when they had only 50 bars left. While surfacing, we had to physically control their ascent to prevent a dangerous rapid rise that could’ve led to decompression sickness (DCS), something they had never even heard of.

Post-Dive Realizations

Lunch was hosted at Canaan Hill Farms, featuring organic dishes of potato, sheep, and native chicken, among others — simple yet incredibly nourishing. Over lunch, I spoke with Jemmel and Jansen. It turns out they were self-taught, with Jansen only on his second actual dive. Jemmel used to dive as a “hookah” diver—breathing surface-supplied air via compressor hoses. He shared stories of labored breathing during deep dives, unaware of the physics and physiology at play.

We discussed decompression sickness, lung overexpansion, nitrogen absorption, and basic dive safety principles. They thanked us sincerely for keeping an eye on them during the dives, even if they didn’t understand our interventions at the time.

Survey Summary: Uson Marine Sanctuary, Caibiran, Biliran

📍 Coordinates: 11.5503300, 124.6117780
🗓️ Date: March 29, 2025

👥 Dive Team:

• Melo Sabitsana – Dive Instructor

• Ikuo Jane Limbaga – Dive Instructor

• Vard Keem Atuel – Dive Master

• Marvel Martinez – Dive Guide

Dive Conditions

• Water Temp: 28°C

• Visibility: 3 meters

• Current: Strong (Dive 1), Mild (Dive 2)

• Weather: Rainy

Key Observations

Coral Health:

• Coral cover: 20–30%, most covered in silt

• Types: Barrel, brain, tube, table, cabbage, soft corals

• Signs of erosion and damage observed

Marine Life:

• Sparse reef fish population

• Notable species: green sea turtle, mackerel, porcelain crab

• Few anemones with Nemo eggs, one lacked guarding female

Human Impact:

• Ghost nets near shore

• Less than 10 plastic items observed underwater

Recommendations

• Reef Restoration: Install artificial reefs at around 10 meters

• Tourism: Currently not suitable for recreational diving

• Education: Urgent need to certify and train local divers

• Monitoring: Annual survey of broader sanctuary area

Final Thoughts

This dive was not just about documentation—it was about reconnection. Reconnection with Biliran’s underwater heritage, with the locals eager to protect it, and with the responsibility we carry as trained divers to guide and educate others. The sanctuary may be buried in silt and forgotten in tourism maps, but it still breathes—still teeming with stories waiting to resurface.

If there's one takeaway from this dive, it’s that conservation doesn't end with discovery. It begins when communities, divers, and nature lovers join hands—not just to explore, but to preserve what remains.

Until the next dive, stay safe, stay curious, and dive with purpose.