As legend goes, millions of years ago a reef rose up and cut off a small lake on the island of Palau in the western Pacific Ocean. A colony of jellyfish was trapped in this lake and had to learn quickly to adapt to the loss of access to the open ocean. Jellyfish Lake (known to the locals as Ongeim’l Tketau) is a fascinating destination, drawing in tourists from all over the globe every year to make the long trip to the natural phenomenon. Lying in the Pacific Ocean, east of the Philippines, Palau is an archipelago, a chain of over 580 islands and home to 20,000 humans. Nearly 1,500 species of fish roam the waters and 500 species of coral can be found in this diverse pocket of Earth. Ongeim’l Tketau is one of eight known lakes in Palau created as sea levels have changed in the area, creating lonely lakes that hold either golden jellyfish, moon jellyfish, or a number of both. Only Ongeim’l Tketau is open to the public and allows tourists to enter the water. The others deny access to humans under the Koror State Rock Islands Conservation Act (1997) that regulates the tourist activity on the island in an effort to protect the marine life.
To reach this particular jellyfish lake requires a flight to the island that usually lasts more than fifteen hours, a quarter of a mile trek up a steep, roped trail, and finally the destination is reached at a slippery dock. Many visitors have witnessed small, usually harmless snakes and colorful birds in the jungle location, making their way quietly through the under-story of lush, tropical trees. The water is teeming with life other than the infamous jellies, including sea squirts, mussels, gobies, and cardinal fish. Birds that prey on fish wait patiently on the shore, eyes trained on the flat surface of the water. From the dock on the northwest corner of the lake, the jellyfish can be seen floating along in the sunshine-infused water, wandering gracefully like clouds in the sky.
They feed on algae that is in abundance and only have to worry about the sea anemone as a predator, leaving the population to flourish to over five million jellies. These jellyfish include both golden jellyfish (Mastigias sp.) and moon jellyfish (Aurelia aurita), and can be seen bouncing along in the water, pushing themselves from the western basin to the eastern basin as the day progresses, allowing them to remain in the sunlight as long as possible. It has been documented that there is algae that lives within the jellyfish and the sunlight allows it to grow. Once the sun sets, the jellyfish dive deeper where the water is nitrogen-rich and also encourages the growth of algae.
If you are looking for a personal, intimate experience with jellyfish, this is the place to go. Scuba diving in the lake is not permitted because it can injure or even kill the peaceful jellies and the toxic layer of hydrogen sulfide about 40-75 feet below the water’s surface is harmful to humans. However, snorkeling is a common activity in the lake and some people simply jump in for a swim. These jellyfish do, indeed, have stingers that they utilize for capturing prey larger and less cooperative than algae, such as tiny fish, but their sting is so weak that most humans do not even feel it in these waters. Those that have felt the minuscule stingers describe it as no more than a “tingling sensation.” Several videos have gone viral on the internet of tourists swimming with the jellyfish in Palau, encouraging others to see and experience the phenomenon for themselves. The warm, tropical waters envelope tourists who frolic and chase the jellies, entangled in harmless tentacles. As long as we continue to respect the natural environment and the creatures in it, Jellyfish Lake will be around to inspire awe for many more generations after our own.