'This animal spared my life': Biologist bitten in head by shark hopes to meet it again

For Hoyos, what happened to him that day in the waters off Cocos Island is the result of normal animal behaviour when confronted with a perceived threat.

"In this case, this bite was like a dog's," he says.

"Have you ever seen how dogs, when another dog gets too close, throw a quick bite? It doesn't hurt it, but it calms the other dog down."

Hoyos - who along with his colleagues attaches acoustic tags to sharks to help pinpoint their mating and spawning grounds as part of his work - was alerted to the shark's presence in the water by tourists.

It was at a depth of 40m, and Hoyos told the captain of the boat he was on that he would be there "for a maximum of five minutes".

He then entered the water and began his slow descent.

Hoyos recalls encountering the shark: "This giant female, measuring between 3 and 3.5m (11.5ft), swam by and headed toward the bottom, and I positioned myself to tag her at the base of her dorsal fin."

But Hoyos, who has tagged many kinds of sharks in his decades-long career, says this animal reacted differently to others.

"Obviously the tip - the metal tip attached to the cable hanging from the probe - goes in, and unlike the other sharks I've tagged that immediately flee, she turns around and stares at me," he recalls.

"I saw her little eye looking at me, and I saw her very calmly turning around."

After Hoyos reached the surface, a young man pulled him aboard the boat, and when the captain saw his condition, he called the park ranger station to report the incident.

Hoyos explained that he didn't feel the pain of his injuries until much later.

"Obviously, I had adrenaline in my system, but the bite didn't hurt that much. What hurt the most was the impact: when the shark bit me - an animal 3m long and at that speed - it was like being hit by a car. In fact, I ended up with a huge bruise all over my jaw; I thought it was broken."

When they docked, a team of paramedics was ready to provide him with emergency care.

Hoyos was lucky: as well as surviving the attack and the subsequent ascent, none of his wounds became infected, and the healing process took less time than anyone could have imagined.

"The doctors told me it was amazing: the attack happened on 27 [September], I had a 34-hour trip, they performed a surgical debridement [removing damaged tissue], and two days later they were already evaluating whether they could perform reconstructive surgery."

It could have been far worse for Hoyos. According to the doctors, a young man who survived a Galapagos shark attack in the same area in 2017 had to remain in a hyperbaric chamber for almost a month because his wounds weren't healing properly.

"They told me my recovery had been incredible. After the surgery, the doctors confessed how worried they had been about an infection, because being on my face, it was a direct path to the brain."

Smiling broadly, Hoyos adds that he is already planning to get back into the water and has a diving trip booked for 14 November.

And he says that after having survived an attack of this magnitude he has even more respect for the animals he studies.

"Many people think the oceans would be better off without sharks, but they really say that because they don't understand the crucial role sharks play in maintaining their delicate balance."

Pointing to the large scar on his cheek, he says: "This is the proof that this female spared my life; I can't put it any other way. And this will allow me to continue speaking well of sharks and advocating for their conservation in the future."

Meanwhile, the Galapagos shark that had Hoyos in its jaws continues its natural life in the depths, and he hopes to see it again. And since he was able to mark it before it attacked him, that possibility exists.

"In January I'm going to Cocos Island, we have a trip from the 20 to 27. And obviously I'm going to Roca Sucia [where the attack happened], I'm going to dive down there," he says, undeterred.