Swimming with a million jellyfish in Palau

First a bit of history, to explain why such a weird and wonderful activity is possible. Limestone is formed on the ocean floor and becomes dry land when geological forces push it up or sea level goes down. Once exposed, rain carves the limestone into caves and hills. That is how the humps of the Chocolate Hills formed. Now imagine that the base of the Chocolate Hills was flooded by a rising sea, leaving each hill a little round island. Actually, you don’t have to imagine it because that is what happened in the Rock Islands, part of the nation of Palau, 500 miles east of the Philippines.

As the sea level goes up and down relative to the hills, sometimes a bit of ocean is enclosed by a ring of hills and becomes a salt-water lake, complete with its original marine wildlife. Most of the wildlife has a hard time adapting to the new environment but the species that can adapt have the new lake all to themselves. In Ongeim’l Tketau lake in Palau, a trapped species of jellyfish adapted by becoming home to an orange algae that produces food for the jellyfish from the sun. The jellyfish no longer needed to hunt so they lost their ability to sting. That brings us to the present where we find ourselves swimming with a million orange jellyfish.


The steep rock walls around the lake mean that the sun only shines in patches on the lake. The jellyfish migrate during the day to follow the sun. The sun was on the opposite side of the lake from where we got in so we swam toward the sunny side for a while before seeing our first jellyfish. Then another, then a few, then more and more until finally there were so many that it was hard to move without bumping into one. The jellyfish swim in every direction and every orientation, making a kaleidoscopic effect that wouldn’t be out of place in a 1970’s movie depiction of an LSD trip. The adult jellyfish are about the size of a grapefruit and feel firm but soft like raw meat. When one unexpectedly swims into your leg, you can’t help but turn around to say “excuse me” since they feel like you are bumping into a person’s leg or arm (and there are usually several other snorkelers in the lake distracted by the jellyfish, so that happens too). Here is a video of what it is like to float among them. And if you want even more, try this one.

Jellyfish Lake is one of the coolest things we’ve seen. Even though we swam there in 2002, we were eager to do it again (and we generally hate repeating ourselves with so much new and exciting stuff to see in the world). We were glad to see that the lake was healthy, as were the beautiful conventional snorkeling sites around the islands such as “Clam City” and “Shark City.”

No zoom lens!
Those blue streaks are all fish

Here is a video showing how dense the sea life can be…with a surprise guest star at the end.

If you look at the images that Google displays when you search for “Palau” you would never know that there is any Human City in the country. Palau is one of the smallest countries in the world with only 20,000 inhabitants but the capital of Koror (where most people live) is a nicely functional town in a beautiful setting. It has several restaurants, a couple department stores (more than downtown Seattle now) and supermarkets overflowing with all the Spam you could ever want.

Spam became a staple all across the Pacific islands during World War II, along with other canned meat products that have largely passed into history back in the US.