Yap Caverns - Yap

Yap Caverns is one of those spots where you just settle in and let the reef show you its rhythm. We love it because it’s not about ticking off big pelagics, though we often see grey reef sharks cruising just outside the mouth. Here, it’s about the feeling of being inside the reef itself. You drop onto the top of the reef, around 10 meters, and then you’re weaving through archways and tunnels. Sunlight shafts filter in, turning the water an incredible iridescent blue-green, especially on a sunny afternoon. Keep an eye on the ceiling for sleeping white-tip reef sharks. We’ve found our best sightings are often tucked into a sandy nook. The walls themselves are alive with little critters – peppered squirrelfish darting into crevices, camouflaged groupers blending so perfectly you almost miss them, and those bizarre variable strombs inching along the rock. It’s an advanced dive, not because of depth, but because you need good buoyancy control to navigate the tight spots without kicking up silt. The currents can pick up, particularly around the exits, so be prepared for a bit of a push. Our favourite moment is always that last tunnel, opening out onto the deep blue where jacks often school, and the reef sharks make their final pass.

Location: Yap, Micronesia, Central & South Pacific
Coordinates: 9.470000, 138.060000
Type: cave
Maximum Depth: 10-30m
Difficulty: Advanced

Best Time to Dive in Yap

The warmest water temperatures in Yap occur in January, averaging 29.0°C. The coolest conditions are in December at 29.0°C.

Monthly Water Temperatures

January: 29.0°C (air: 27.5°C)
February: 29.0°C (air: 27.5°C)
March: 29.0°C (air: 27.5°C)
April: 29.0°C (air: 27.7°C)
May: 29.0°C (air: 28.0°C)
June: 29.0°C (air: 27.6°C)
July: 29.0°C (air: 27.6°C)
August: 29.0°C (air: 27.7°C)
September: 29.0°C (air: 27.9°C)
October: 29.0°C (air: 27.9°C)
November: 29.0°C (air: 28.0°C)
December: 29.0°C (air: 28.0°C)

Nearest Dive Centres to Yap Caverns

Manta Ray Bay Resort & Yap Divers
Yap Divers - Manta Ray Bay Hotel - ["PADI"]

Marine Life in Yap

Home to 316 recorded species including 253 reef fish, 20 hard corals, 17 sea cucumbers, 13 sea snails & nudibranchs, 3 clams & mussels, 3 sharks & rays.

Notable Species

Bristle-toothed Surgeonfish (Ctenochaetus striatus) - Reef Fish
Blue Parrotfish (Scarus oviceps) - Reef Fish
Clown Tang (Naso lituratus) - Reef Fish
Blunt-head Parrotfish (Chlorurus microrhinos) - Reef Fish
Blackfin Soldierfish (Myripristis adusta) - Reef Fish
Black sea cucumber (Holothuria atra) - Sea Cucumbers
Bluefish (Kyphosus vaigiensis) - Reef Fish
Long-nosed Parrotfish (Hipposcarus longiceps) - Reef Fish
Sea chub (Kyphosus cinerascens) - Reef Fish
Threadfin (Chaetodon auriga) - Reef Fish
Greenfish (Stichopus chloronotus) - Sea Cucumbers
Maori Wrasse (Cheilinus undulatus) - Reef Fish
Black-barred Surgeonfish (Acanthurus nigricauda) - Reef Fish
Bullethead Parrotfish (Chlorurus sordidus) - Reef Fish
Small giant clam (Tridacna maxima) - Clams & Mussels
Argus Grouper (Cephalopholis argus) - Reef Fish
Schlegel's Parrotfish (Scarus schlegeli) - Reef Fish
Stony coral (Porites cylindrica) - Hard Corals
Pinkfish (Holothuria edulis) - Sea Cucumbers
Banded Goatfish (Parupeneus multifasciatus) - Reef Fish

Recommended Packing List for Yap Caverns

Based on average water temperature of 29.0°C.

Shorty or Rashguard - warm 29°C water needs minimal exposure protection
Mask - essential for every dive
Fins
BCD - buoyancy compensator
Regulator - your most safety-critical piece of gear
Dive Computer - tracks depth, time, and NDL
Surface Marker Buoy (SMB) - essential for boat pickups
Dive Torch - useful for crevices and colour at depth
Underwater Camera - capture your diving memories