Bumphead parrotfish aggregate off a reef before spawning

Palau is an underwater paradise, with more than 700 coral species and 1,500 fish species. Three converging, nutrient-rich ocean currents fuel Palau’s rich biodiversity and create some of the most diverse dive experiences on the planet. Located just two hours by plane southwest of Guam, the tiny island nation is within easy reach of the USA.

Palau’s shark-filled drift dives, up-close manta encounters, and unique jellyfish snorkel are world-famous. You may also experience blackwater diving and – if you’re lucky – swim with whales, dugongs or crocodiles. I travel to Palau to photograph the colorful reef fish, fish larvae and the spawning aggregations. Thousands of fish gathering to reproduce in one place is one of the most exciting events you will ever witness.

Bohar Snapper Spawning
Every month, 5-6 days leading up to the full moon, thousands of bohar snapper (Lutjanus bohar) aggregate early in the morning to spawn at several deep reef sites in Palau. After gathering near the reef, the massive school forms a tight ball and swims out into the blue water. As the school rises into the water column, tornados of rubbing fish bodies erupt toward the surface, producing white clouds of gametes everywhere you look.

Twin-spot red Snapper (Lutjanus bohar) spawning aggregation.
Twin-spot red snapper (Lutjanus bohar) spawning aggregation.

The fish swim back to the reef, then back out into the blue – spawning again. They repeat this pattern many times.  The chaotic spectacle goes on for almost an hour. Spawning occurs over several days and climaxes around the full moon.

Bumphead Parrotfish Spawning
Bumphead parrotfish (Bolbomeotpon muricatum) aggregate to spawn around the time of the new moon in certain reef passages in Palau. These large aggregations consist of hundreds of fish, mostly smaller adults. Multiple males (have pale forehead) will spawn with a single female. Spawning takes place in the early morning. The spectacle lasts for about one hour, before the fish separate.

Bumphead parrotfish (Scarus perrico) spawning in the blue water off a deep reef in Palau.
Bumphead parrotfish (Bolbometopon muricatum)  spawning in the blue water off a deep reef in Palau.

Camouflage Grouper Spawning
Camouflage groupers (Epinephelus polyphekadion) aggregate in specific reef passages for several days around the new moon during the summer months. Males compete for and pair with females during the daylight hours. Spawning takes place late in the evening with currents ripping out to sea. The action starts with two fish racing up several meters into the water column. In a flash they turn, release milt and eggs, and bolt back down to the safety of the reef. A few seconds later a second pair races up in unison. Then a third and a forth. Within minutes, the reef erupts like a firework display.  Sharks race in to hunt on the distracted fish.  In less than half an hour, hundreds of groupers have reproduced.

A pair of camouflage groupers (Epinephelus polyphekadion) spawning at night in Palau. Females can easily be distinguished from males by their massively swollen belly filled with hydrated eggs.
A pair of camouflage groupers (Epinephelus polyphekadion) spawning at night in Palau. Females can easily be distinguished from males by their massively swollen belly filled with hydrated eggs.

Interested in seeing these incredible spawning events underwater? Join my friends at Unique Dive Expeditions in Palau. Here are my favorite images about Palau’s Marine Life: