Dr. Mauricio Hoyos, a seasoned marine scientist from Mexico, embarked on what he expected to be a routine research dive off Cocos Island, located hundreds of miles southwest of Costa Rica, on a recent Saturday. His mission: to tag sharks for crucial conservation studies.
Mere minutes into his descent to 123 feet, a nine-foot-long Galápagos shark, a majestic migratory species, came into view. With practiced precision, Dr. Hoyos aimed his pole spear, releasing a tag that successfully embedded near the shark’s dorsal fin.
But the day’s predictability ended there. What followed was a sudden, heart-stopping turn of events as Dr. Hoyos, 48, transitioned from observer to target.
From just about a meter away, the shark surged forward with astonishing speed, its massive jaws gaping wide.
“She turned sideways in my direction; it was really fast,” Dr. Hoyos recounted in a later interview. “It was wide open; my whole head was inside of her mouth in less than a second.”
He recalled hearing a distinct cracking sound, which he quickly realized was merely the intense pressure. “But it was just pressure,” he said. “As soon as she felt my skull, she released me. She opened and swam away.”
His mask instantly filled with a mix of blood and water, having been dislodged by the impact. Alarmingly, the shark’s teeth had also sliced through the air hoses of his scuba gear.
Though temporarily blinded, he sensed the shark’s departure by its fading shadow.
“I saw the shadow twice in front of me,” he said, a chill in his voice. “If she wanted, she could have killed me.”
Grappling with blood loss and dwindling air, he began a deliberate, slow ascent to ensure proper decompression, his body flooded with adrenaline. After a series of careful exhalations, he reached the surface, on the verge of collapsing. His team quickly pulled him onto their skiff and rushed him to Cocos Island, where park medics provided initial first aid before his transport to the mainland.
Speaking from a hospital bed in San José, Costa Rica’s capital, Dr. Hoyos shared details of his ordeal. He was awaiting surgery on his jaw after receiving stitches for lacerations on his scalp and punctures on his face. In total, he sustained 27 injuries—a grim count, one for each of the 27 teeth that had apparently pierced his flesh.
Dr. Hoyos was leading a team for Fins Attached Marine Research and Conservation and Pelagios Kakunjá, studying shark migratory patterns along an underwater mountain ridge near Cocos Island, over 400 miles off mainland Costa Rica. This vital research aims to inform conservation efforts against commercial fishing. The expedition had begun on September 20, with the first dives commencing two days later.
His terrifying encounter happened on the sixth day of their research dives.
Dr. Alex Antoniou, director of Fins Attached, highlighted Dr. Hoyos’s unique advantage. “How he responded was probably a lot different from a normal diver,” Dr. Antoniou noted. “He understands shark behavior.”
“It’s the wild,” Dr. Antoniou added, emphasizing nature’s unpredictability.
A veteran with three decades of experience, Dr. Hoyos has tagged countless species, including formidable great white and tiger sharks. He recounted how his Saturday afternoon dive transformed into an extraordinary tale of survival in the deep, a realm where marine scientists navigate with a blend of scientific rigor, defensive instinct, and profound respect for the ocean’s power.
His diving partner, present in the water, could only watch, unable to intervene until the shark had moved away.
“My main concern was I felt like I could not breathe,” Dr. Hoyos said, describing the terrifying sensation of his compromised air supply.
“To be honest it was like in slow motion,” he reflected. “But my mind was very calm. I was thinking the whole time about what to do.”
He had tagged other sharks during the trip, including Hammerheads and whale sharks. Galápagos sharks were usually easier to tag because, as top predators, they are generally not as afraid of humans, he said.
He believes the female shark’s aggressive reaction was a startled defensive response to being tagged.
“She was heading down and never saw me, and then she felt the puncture” of the tag, Dr. Hoyos clarified. “It was a defensive bite. She wanted me to stay away from her personal space.”
Remarkably, it was his first time being bitten in 30 years of marine research.
“She was scared also. It was not her fault,” he concluded, demonstrating a deep understanding and empathy for the animal’s natural instincts.