Ulong Channel, One of Palau's Best Dive Sites

Grey reef and white tip sharks, school of barracudas, jacks, snappers, groupers, spotted eagle rays... Is there a dive site, which has it all? Yes, absolutely!
Let me accompany you to my favorite dive site here in Palau - the Ulong Channel. Starting from the mouth of the channel we will enjoy the first highlight: patrolling grey reef and white tip sharks. With some luck, we can even see a school of baby grey reef sharks. From there we are going to drift into the channel. The channel itself has a sandy bottom, surrounded by a breathtaking coral garden. 

Don't miss out on the grouper mating season, where hundreds of big groupers are inside the channel. We must watch out for our friend the titan triggerfish though. The sandy channel is perfect for their nests and they're getting pretty protective about it. Towards the end of the dive, we will pass some massive lettuce corals. Snappers chose them to be their home. Ulong Channel is an absolute must-do if you're in Palau! (Anja Bittner, PADI Instructor - connect on FB)

Amongst the many fantastic dive sites in Palau, there are three which are a must for every scuba diver. Blue Corner Palau is one of the single best dives in the world and famous for its sharks and described in our blog The magic of diving Blue Corner Palau - German Channel Palau known for manta madness and last but not least Ulong Channel Palau known for sharks, grouper mating and its beautiful corals.

When you dive Ulong Channel, you’ll have it all. Dropping at the mouth of the channel you’ll observe sometimes hundreds of reef sharks amongst other schooling fish. Drifting into the channel is as exciting - fantastic soft and hard corals, beautiful sea fans, and, depending on season and moon phase, mating groupers, sharks, or triggers.

Diving Ulong Channel Palau

General Information

This channel is sometimes referred to as Ngerumekaol Pass. Due to the close proximity of Ulong Island, it is commonly known as Ulong Channel. Ulong Island is a great place for a picnic because of its beautiful beaches and its historical significance. Ancient Palauans painted a series of petroglyphs on the high cliffs of the island. Be sure to have your Dive Guide point out the petroglyphs as you pass the western side of Ulong Island.

Diving the famous Ulong Channel Palau

The dive usually starts along the reef at the northern side of the channel by dropping down to 60 feet (20 m). Keep the reef on your left side. About 10 minutes into the dive you will approach a sandy run-off, this is the entrance to the channel. Grey Reef and White Tip Sharks are always on patrol here and the current is usually strong. Hook on to one of the rocks and watch the action. Once you leave this area be prepared for one of the most exciting drift dives in Palau. Let the current carry you into the channel. One of the most impressive sights the diver will see is an enormous section of lettuce coral that has grown from the bottom of the channel to a height of 15-20 feet (5 to 7 m). The eastern end of the channel is deeper and the bottom is mostly sand.

Ulong Island Palau - Location of the dive site

The dive site is located on the West side of Ulong Island

Baby Sharks at Ulong Channel Palau

Reef Formation

Ulong Channel runs west to east and cuts only partially through the western barrier reef. The barrier reef runs perpendicular to the channel. The sandy bottom of the channel is 10 to 40 feet (3 to 13 meters) deep and is decorated with numerous coral heads and coral formations. The sides of the channel start just below the surface and gradually slope toward the sandy bottom.

The Rich Marine Life at Ulong Channel Palau

Gray Reef Sharks, stingrays, schools of jacks, snappers, barracuda, and batfish are frequently seen at the entrance. When the moon is full, during the months of April, May, June, and July, thousands of groupers gather here to spawn. Groupers are usually solitary fish, but during this time they have been seen to school. Titan Triggerfish also use this area to nest. When Titan Triggerfish are nesting they become extremely territorial and protective of their nest sites. Titan Triggerfish will dig out large depressions in the sandy bottom to lay their eggs. To avoid being attacked and bitten by jealous triggerfish, divers should keep their distance.

Shark mating at Ulong Channel Palau

Fascinating Facts about Ulong Channel

Titan Triggerfish nests may have as many as 430,000 eggs clustered together in a fist-sized ball. When Triggerfish are nesting they can become quite nasty. Keep your distance!