This article first appeared in Issue 14 of our digital magazineCURIOUS .
Twelve thousand eld ago , modify ocean levels left a pocket of water isolated from the rest period of the sea , trap in its confines a mathematical group of jellyfish . The unique race ca n’t be found anywhere else on Earth , but exist in their jillion in Palau ’s Jellyfish Lake .
Jellyfish sovereignty supreme inside one of 70 saltwater lake on an island off the coast of Koror , Palau , in the westerly Pacific , that ’s uninhabited by human beings . The pee bodies were once get in touch to the ocean but got cut off thousands of years ago , make unique pockets of ecosystem and unusual food chains including a harbour for cnidarian .
The lake is home to millions of jellyfish.Image credit: zaferkizilkaya/Shutterstock.com
It ’s estimated thatJellyfish Lakemay have become isolated from the sea as far back as 12,000 years ago , trapping its inhabitants . This was due to rising ocean levels depositing them in the lake before recede again , leaving them behind .
Its house physician areMastigias papua etpisoni , also known as the golden jellyfish . The unique race is named after former President Ngiratkel Etpison and this marine lake is the species ’ exclusive home .
They survive in partnership with symbiotic algae that live in their tissue paper . Collectively , these dinoflagellate are recognize as zooxanthellae , a terminal figure used to distinguish unmarried - celled microorganism that live inside a range of maritime invertebrates including demosponges , corals , Portuguese man-of-war , and nudibranchs .
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Jellyfish are n’t the only wildlife found in the lake , which is draw at its bound by Rhizophora mangle trees whose tangled roots are bustling with marine invertebrates . It ’s also family to moon jellyfish , but the golden jellyfish are by far the most numerous . During a peak for the lake ’s residents back in 2005 , it ’s figure there were around 30 millionM. papua etpisoniin Jellyfish Lake , but most of the time there are thought to be nearer to 5 million swimming around .
While they can remain easy without the fear of predator , the jellyfish have a job to do . To control their tenant zooxanthellae get the sunlight they necessitate for photosynthesis , they must rotate and drown around the lake ’s surface weewee if they ’re to meet any DOE and nutrient in return .
The lake ’s get together denizen are n’t its only peculiar characteristic , as the weewee column is separate up with all the complexity of a B52 stroke . In total , it ’s around 400 meters ( 1,312 foot ) long and 30 meters ( 98 feet ) deep , but not all of the lake is secure to float in .
At a depth of 13 to 15 metre ( 43 to 49 fundament ) baby-sit a pink layer of bacterium that sparkle can not get through , create a roadblock beyond which no sunlight or oxygen can give . This means the bottom piddle stratum is made up of poisonous dissolved hydrogen sulfide gas , explains theCoral Reef Research Foundation .
So , are you going in ?
How to get there : The good way to visit Jellyfish Lake is as part of a tour as environmental fees and permits are need to swim among the jellies , and they can gather you from Koror .
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