The Big Drop Off - Rock Islands
The Big Drop Off is exactly that, a wall that just keeps going, down to an almost ridiculous 285 metres. We love it because it delivers on both the macro and the pelagic, right from the first fin kick. Drop in and you’re immediately enveloped by the shallows, a flurry of fusiliers and parrotfish darting through the soft corals. Our favourite part has to be the overhangs, look closely and you’ll spot Twinspot Hawkfish perched like tiny sentinels, or the shy Longface Emperor peeking out. As you drift down, the wall itself becomes the star, a tapestry of massive sponges and plate corals, each crevice home to something new – maybe a Fluted Clam, or a Bicolor Angelfish flashing its electric hues. Keep one eye on the blue, though. Blacktip sharks often cruise by, and we’ve even been lucky enough to spot a Chambered Nautilus making its slow, deliberate journey. It’s a site that rewards patience and a keen eye, perfect for divers who appreciate both the grandeur of a deep wall and the intricate beauty of the reef’s smaller residents.
- Location
- Rock Islands, Palau, Central & South Pacific
- Coordinates
- 7.101426, 134.249650
- Type
- wall
Marine Protected Area: Ngemelis Island Complex
Best Time to Dive in Rock Islands
The warmest water temperatures in Rock Islands occur in October, averaging 30.0°C. The coolest conditions are in February at 28.4°C.
Monthly Water Temperatures
- January: 28.8°C
- February: 28.4°C
- March: 28.8°C
- April: 29.3°C
- May: 29.8°C
- June: 29.9°C
- July: 29.8°C
- August: 29.7°C
- September: 29.9°C
- October: 30.0°C
- November: 29.9°C
- December: 29.6°C
Nearby Dive Sites in Rock Islands
- Big Drop Off - 20-40m (wall)
- Blue Corner
- Blue Corner (and Blue Holes)
- Blue Holes
- Chandelier Cave (cave)
- Chandelier Caves - 34m to 98m
- Chuyo Maru (wreck)
- German Channel - 21m (drift)
- Helmet Wreck - 34m to 98m (wreck)
- Iro - 16-131ft (5-40m) (wreck)
- Iro Maru Wreck Palau - 27m (wreck)
- Jake SeaPlane (wreck)
- Jellyfish Lake - Ongeim’l Tketau - 12m
- Lighthouse Channel (drift)
- Mandarinfish Lake - 16-131ft (5-40m)
Nearest Dive Centres to The Big Drop Off
Marine Life in Rock Islands
Home to 198 recorded species including 171 reef fish, 15 sea cucumbers, 4 clams & mussels, 4 sea snails & nudibranchs, 2 starfish, 1 sea urchins.
Notable Species
- Boring Clam (Tridacna crocea) - Clams & Mussels
- Small giant clam (Tridacna maxima) - Clams & Mussels
- Black sea cucumber (Holothuria atra) - Sea Cucumbers
- Orange-lined Triggerfish (Balistapus undulatus) - Reef Fish
- Pinkfish (Holothuria edulis) - Sea Cucumbers
- Saddleback Butterflyfish (Chaetodon ephippium) - Reef Fish
- Greenfish (Stichopus chloronotus) - Sea Cucumbers
- Bristle-toothed Surgeonfish (Ctenochaetus striatus) - Reef Fish
- Burrowing urchin (Echinometra mathaei) - Sea Urchins
- Bullethead Parrotfish (Chlorurus sordidus) - Reef Fish
- Tigerfish (Bohadschia argus) - Sea Cucumbers
- Threadfin (Chaetodon auriga) - Reef Fish
- Telescopefish (Epibulus insidiator) - Reef Fish
- Banded Goatfish (Parupeneus multifasciatus) - Reef Fish
- Kihikihi (Zanclus cornutus) - Reef Fish
- Banded maori wrasse (Cheilinus fasciatus) - Reef Fish
- Sunburst Butterflyfish (Chaetodon kleinii) - Reef Fish
- Curryfish (Stichopus vastus) - Sea Cucumbers
- Butterfly fish (Chaetodon vagabundus) - Reef Fish
- Honeycomb Grouper (Epinephelus merra) - Reef Fish
Recommended Packing List for The Big Drop Off
Based on average water temperature of 29.5°C, currents 13 cm/s.
- Shorty or Rashguard - warm 30°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