THE EXPEDITION

EXPERIENCE REQUIRED - ADVANCED OPEN WATER LEVEL WITH 50 DIVES MIN

This is not just another trip—this is a rare double spawning expedition, combining two of Palau’s most extraordinary natural events into one perfectly timed experience.

Only twice a year—January and February—the lunar cycles align to make this possible. Miss these windows, and the opportunity is gone.

Choose between a land-based expedition or the full immersion of a liveaboard, with a schedule built around early morning dives and optional late-night sessions, ensuring you’re in the water exactly when the action unfolds.

We begin with one of the ocean’s most elegant spectacles—the spawning of the Moorish Idol.

Over several days, you’ll witness what is believed to be one of the largest aggregations of Moorish Idols ever documented, with over a thousand individuals gathering in synchronized motion. What follows is a mesmerizing display—graceful, rhythmic, almost hypnotic—as these iconic fish rise into the water column to spawn.

Then, just as that chapter closes, the pace shifts.

We transition into the high-energy chaos of the Twin Spot Snapper (Lutjanus bohar) aggregation. Here, the numbers surge into the tens of thousands, forming a dense, fast-moving wall of fish that erupts into a full-scale spawning event—often accompanied by reef sharks and larger predators drawn in by the intensity.

Two completely different spectacles.
One perfectly timed expedition.

Once the spawning events have passed, the adventure continues as we explore the very best of Palau—diving manta cleaning stations, shark-filled channels, dramatic caverns, blue holes, swim-throughs, and even the surreal experience of Jellyfish Lake.

Elegant. Explosive. Unrepeatable.

This is one of the most unique dive expeditions you will find anywhere in the world—two rare natural events, perfectly aligned in a single trip.

PALAU

Palau is widely regarded as one of the finest dive destinations on the planet—and for good reason. Its reefs are shaped by dramatic underwater topography, including sheer drop-offs, blue holes, caverns, caves, and fast-moving channels. Visibility is often exceptional, regularly reaching up to 100ft (30m), giving you that true “endless blue” feeling.

Wreck dives closer to Koror offer a different atmosphere, where visibility is typically reduced to around 15–45ft (5–15m)—but what they lack in clarity, they more than make up for in history and character.

Palau can be dived year-round, though the wetter season generally runs from July through October. Water temperatures are consistently warm, ranging between 81–86°F (27–30°C), making a 3mm wetsuit ideal for most conditions. That said, Palau likes to keep things interesting—seasonal thermoclines can drop temperatures into the mid-60s°F (23–26°C), especially on deeper dives.

Most sites are accessed via 45–60 minute speedboat rides from Koror, with the prime diving areas located around Ngemelis Islands and Peleliu—home to some of the most iconic dives in Micronesia. For this reason we choose a liveaboard experience to maximise our time on the ocean, offering four dives a day with early starts and late sunset dives.

Currents are a defining feature of diving in Palau. Driven by the Pacific Ocean, they create the conditions that make this destination so spectacular—but they also demand respect. Many sites are best suited for experienced divers, and a reef hook is essential, particularly on the outer reef walls like the legendary Blue Corner, where you’ll hook in and watch the ocean unfold in front of you.

For those with a passion for history, Palau also delivers. The waters around Koror are scattered with World War II wrecks, from cargo ships and transport vessels to navy destroyers and even Japanese Zero aircraft. Many are remarkably intact and easily accessible, offering a completely different—but equally compelling—side of Palau diving.

MOORISH IDOL AGGREGATION

During the months of January and February, one of the ocean’s most graceful and rarely witnessed events unfolds in the waters of Palau.

Across a handful of key sites, thousands of Moorish Idols (Zanclus cornutus) begin to gather—slowly at first, then building into one of the largest aggregations ever documented anywhere in the world.

What follows is nothing short of mesmerizing.

These iconic fish, known for their striking shape and flowing dorsal streamers, move together in a synchronized display—circling, rising, and interacting in a fluid, almost hypnotic choreography as they prepare to spawn. It’s calm, controlled, and incredibly precise… a complete contrast to the chaos of other spawning events.

But beneath that elegance lies tension.

This gathering does not go unnoticed.

As the aggregation builds, so too does the presence of predators. Hundreds of sharks—including grey reefs, blacktips, and larger pelagic species—move into the area, drawn by the sheer density of life. The result is an extraordinary balance of beauty and intensity: a peaceful ballet of Moorish Idols unfolding in the presence of powerful hunters.

It is, without question, one of the best times of year to experience Palau’s thriving shark population at its peak.

Graceful. Rare. Electrifying.

This is not something you stumble upon.
This is something you plan for… and never forget.

TWIN SPOT SNAPPER SPAWNING

In the days leading up to the full moon, something extraordinary begins to build beneath the surface of Palau. From across the reef, thousands—often tens of thousands—of Twin Spot Snapper (Lutjanus bohar) converge on the outer promontories, drawn together by instinct, timing, and the pull of the lunar cycle.

What starts as scattered groups quickly transforms into a dense, fast-moving mass of fish—layer upon layer stacking in the current as anticipation builds for the main event.

We begin our expedition ahead of the full moon, diving Palau’s iconic current-swept sites to prepare for what’s coming. These are not just warm-up dives—they are part of the story. You’ll feel the energy building in the water, the numbers increasing day by day, until everything is set.

Then comes the moment.

Before first light, we head out. Engines running in the dark, anticipation high. As the sun begins to rise over the Pacific, we drop into the water and descend into the blue.

Out of the depths, they appear.

A towering wall of snapper rises from below, tightening into formation as the current pushes through the reef. Then suddenly—everything erupts. The entire aggregation surges upward in a synchronized explosion of movement, releasing clouds of eggs and milt into the water column.

It’s chaotic. It’s raw. It’s nature at full throttle.

And you’re right in the middle of it.

This intense burst of life doesn’t go unnoticed. The commotion draws in apex predators—bull sharks, oceanic blacktips, and grey reefs—circling the edges of the aggregation, waiting for opportunity. The contrast is electric: a living storm of snapper surrounded by powerful hunters moving effortlessly through the chaos.

There’s no better way to describe it—this is an underwater firework display, a sensory overload of motion, scale, and energy that few divers on the planet ever get to witness.

Miss the timing… and it’s gone……….Get it right… and you’ll never forget it.

PALAU SIREN - LIVEABOARD

LIVEABOARD EXPEDITION

ALL LIVE-ABOARD RATES ARE BASED ON PER PERSON.

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THE RATES

ALL CABINS ARE BASED ON SHARED OCCUPANCY

SPAWNING 10 DAY ITINERARY - 16 Spaces - $6,640

CURRENTLY 2027 RATES

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FULL MOON MOORISH IDOL & RED SNAPPER COMBO EXPEDITIONS