Caño Island sits about 20 kilometres off the Osa Peninsula, and getting there already feels like an expedition. Day boats depart from Drake Bay and Sierpe, typically running 45 minutes to an hour depending on conditions. There are no liveaboards operating here — it's strictly a day-trip destination, which suits most travellers well enough given the island's biological reserve status means visitor numbers are managed by SINAC permits.
Visibility is genuinely impressive when the Pacific cooperates, often stretching 15 to 25 metres, though upwellings from July through September can cloud things up considerably. Depths across the main sites — Bajo del Diablo, Punta Arenas, and Paraiso — range from a comfortable 5 metres for snorkellers down to around 30 metres for divers.
Currents vary from gentle to surprisingly pushy depending on tidal cycles, so your dive guide's local knowledge matters more than usual here. I'd call this intermediate territory rather than beginner-friendly.
The marine life is what draws people, and it delivers. Whitetip reef sharks rest on the sandy bottom in loose groups, occasionally in surprisingly large numbers. Bull sharks appear with more regularity than most operators advertise, particularly at depth during the green season. Nurse sharks tuck under ledges, sea turtles drift through mid-water, and enormous schools of jacks and snappers fill the blue.
Hard coral coverage is reasonable by Pacific standards, though bleaching events have taken a toll in warmer El Niño years and full recovery remains patchy in places.
Local operators based in Drake Bay — outfits like Drake Divers and Cocalito Lodge — are competent and well-equipped, with bilingual guides who know these sites thoroughly.
December through April offers the calmest seas and best visibility; open-water certification minimum, though Advanced is strongly recommended.