While there are many incredible places to dive and snorkel in Palau, one of the most interesting adventures you can undertake involves a short hike and a simple snorkel. Jellyfish Lake is located in a jungle, and was once part of the ocean. Grab your mask and snorkel, and leave your tanks behind – no diving is allowed here!
The Adventure
After taking a quick ride on a speedboat, then hiking for about ¼ mile through a very pretty jungle, you’ll emerge onto a wooden dock, where you can get ready to swim with the jellies. In case you’re wondering why no SCUBA is allowed, it is partially because bubbles from divers were being trapped beneath the jellies, forcing them up against the walls, and up into the mangrove roots, wounding and sometimes killing them.
Geologic Formation
The island was once a coral reef, which has been pushed up and out of the ocean over the millennia. Marine lakes like this one are still connected to the sea, and they are subject to tidal changes. While the bottom of the lake is at about thirty meters, flora and fauna is restricted to the top forty-five feet of the lake, as there is no oxygen below that level. Instead, high levels of hydrogen sulfide permeate the water below that level, preventing any organic life from surviving. The presence of this toxic compound is just one more reason why diving is prohibited. It can enter our bloodstream via our skin, and then bind to hemoglobin molecules, preventing adequate oxygen absorption and eventually leading to death from oxygen deprivation.
The Jellies, and Other Life at Jellyfish Lake
There are more than an estimated five million golden jellyfish living in the lake, which look very much like the jellyfish you will encounter while diving Palau’s reefs. At first light on sunny days, the jellyfish begin a migration from the western basin, heading toward the early morning light that strikes the eastern edge first. As shadows descend on the lake, they reverse course.
Despite a myth that these jellyfish are stingless, they do in fact carry a small amount of venom within their bodies. The amount is so minute, though, that you will not feel it unless you are either allergic to jellyfish, or if you catch a jelly to the face. By swimming slowly and cautiously, you will prevent this from happening, and you will also prevent any injury to the jellyfish.
This daily journey prevents them from coming too close to the predatory Entacmea medusivora anemone, which live along the edges of the lake, and which lie in wait with outstretched tentacles, capturing and consuming any jellies that come too close.
Besides the golden jellyfish and the anemones, there are more than a million moon jellyfish, which spend the day down deeper than the golden jellies, and which are rarely ever seen. Along the edges of the lake, where the mangrove trees extend their roots into the water, you may find cardinal fish and gobies, mussels, and sea squirts.
A trip to Jellyfish Lake is almost a requirement for anyone who travels to Palau on holiday. Charters to the lake book quickly, so be sure to make reservations well in advance, for your chance to enjoy this amazing site.