Sept 25 – Oct 6, 2025 | Cocos Island Trip Report | Sea Hunter

We set sail from Puntarenas with a full group of divers from the United States and Germany, all eager for the adventure ahead. The crossing was somewhat rough, but spirits stayed high as everyone settled in for the two-day journey. By the time we reached Cocos Island on the morning of the 28th, the excitement on board was palpable… and the diving did not disappoint!!

Our first day underwater was full of surprises. Even the check-out dive in Chatham Bay brought unexpected hammerhead activity, followed by eagle rays gliding gracefully through Manuelita Channel. At Manuelita Outside, several schools of hammerheads passed over the cleaning stations, and a manta ray made a brief appearance. What a promising start to the week!

The morning dives at Dirty Rock this week were particularly active, with both cleaning stations buzzing with life. Large groups of hammerheads circled in full view of the divers and there were schools of jacks blanketing the reef. In the afternoon, we explored Punta María and Pájara, where we encountered marble rays, whitetip reef sharks, and a few of Cocos’ endemic reef fish among the rhodoliths.

Day three brought us to the legendary Alcyone. The moment we reached the seamount, the action was nonstop — a massive school of over 200 hammerheads drifted in formation while Galapagos and blacktip sharks patrolled the cleaning station. Visibility was low and the water cool, but the energy was electric. Later that day, a giant manta cruised above the group at Manuelita Outside, and Viking Rock offered a slower-paced dive full of small creatures — pipefish, lobsters, and moray eels — with a few hammerheads passing in the blue to keep things interesting.

The fourth day delivered one of the epic highlights of the trip. At Dos Amigos Pequeño, we simply settled on the bottom and watched the show unfold: Galapagos, blacktip, silvertip, and hammerhead sharks continuously swept past the cleaning station in an unforgettable 45-minute display. The next dive at Dirty Rock was just as thrilling; despite limited visibility, groups of hammerheads entered the cleaning stations repeatedly, surrounded by clouds of jacks shimmering in the current. By the time we surfaced, no one could quite believe the spectacle we had just witnessed.

On day five, Alcyone was on fire again. An enormous school of more than 100 hammerheads encircled the group for nearly the entire dive while Galapagos sharks and a sleek tiger shark joined the mix near the cleaning station. Later at Porites we had encounters with several silvertips and a tiger shark passing directly in front of our divers (the perfect finale to an incredible day!).

Day six continued the streak of exceptional diving. We descended at Dirty Rock into a breathtaking scene: hundreds of hammerheads — perhaps 200 to 300 individuals — surrounded us for more than half an hour, often passing just meters away. A graceful manta ray and several Galapagos sharks added to the show. At Manuelita Outside, we found more synchronized hammerhead schools cruising near the sandy bottom, a colorful frogfish, and marble rays scattered across the reef. Our afternoon dive at Dirty Rock again delivered big action with Galapagos sharks, hammerheads, and immense schools of jacks filling the water column.

Our final day at the island brought a few final encounters with hammerheads and silvertips before we began our maneuver and set course back to Puntarenas around 15:00. The return crossing started out choppy but soon smoothed into calm seas. This was a fitting close to a week that reminded us why Cocos Island remains one of the world’s truly magical dive destinations.