Islas Marietas
Puerto Vallarta · Mexico
The Islas Marietas are a protected UNESCO-recognised national park 35 km offshore, formed by volcanic collapse. The submerged lava tunnels and arches shelter massive schools of fish and a dense reef community. The surface-famous Hidden Beach is above water — the diving equivalent is the swim-throughs and caverns beneath the waterline, home to white-tipped reef sharks resting on sandy floors. Giant manta rays are regular visitors at the cleaning stations on the exposed northern faces.
Conditions
Depth
5 to 30 m
Open water and up
Current
Usually still
Can pick up on the edge
Visibility
12 to 20 m
Clearest in the calm season
Water
21 to 29°C
3mm wetsuit or shorty
Month by month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Water (°C) | 21 | 21 | 22 | 23 | 25 | 27 | 28 | 28 | 28 | 27 | 24 | 22 |
| Vis (m) | 12 | 12 | 15 | 15 | 15 | 15 | 12 | 10 | 10 | 12 | 12 | 12 |
| Current | Moderate | Moderate | Gentle | Gentle | Still | Still | Still | Still | Gentle | Gentle | Moderate | Moderate |
Your chances of seeing each animal
Cortez Rainbow Wrasse
Last confirmed May 27, 2026 · 51 records
Almost always
Nearly every dive
Schooling Scad (Jack)
Last confirmed May 20, 2026 · 3 records
Likely
About 6 in 10 dives
Pufferfish (Bullseye)
Last confirmed Jan 28, 2025 · 4 records
Likely
About 6 in 10 dives
White-tipped Reef Shark
Expected
Known here, not yet in recent logs
Yellowfin Grouper
Expected
Known here, not yet in recent logs
Green Moray Eel
Expected
Known here, not yet in recent logs
Rosy Lionfish
Expected
Known here, not yet in recent logs
Pacific Reef Octopus
Expected
Known here, not yet in recent logs
Gear