Kakaban

Kakabanisland is part of theDerawan Islands,East Kalimantan,Indonesia.

The island has an area of 774.2 hectares (1,913 acres) and is quite steep. Its limestone cliffs are covered with densejungleright down to the water's edge. The wall drops to 180 metres (590 ft), and currents can be strong with upwelling, downcurrent and reversing directions.

The most distinctive feature is the huge brackish water lake in the middle of the island, in the local dialect Kakaban means "hug" as the island hugs the lake from the surrounding seawater.

Jellyfish Lake

One of the harmless-to-humans jellyfish of Kakaban

In the middle of this island is amangrove-fringed lake, slightly above sea level, where thousands of jellyfish live, making it interesting for diving. The jellyfish consist of four different species which do not have the ability to harm humans with their stinging cells. They areAurelia auritawith a transparent body,Tripedalia cystophorawhich is fingertip size,Mastigias papuais like a green-brown bulb, andCassiopea ornatawhich is an upside-down jellyfish with uprighttentacles.Although they cannot sting humans, they still have poison and can sting their prey. Similar lakes exist in thePhilippines(Siargao), and inPalau,withJellyfish Lakebeing the best known.

The lake has warm brackish water and the bottom is covered withmarinegreen algae.There are other animals, includingsea cucumbers,gobies,sea anemones,tunicates,crustaceans,nudibranchs,orange purple clamsandyellow clamson the branches, andsnakes.

The lake is at most 17 metres (56 ft) deep with poor visibility and is 10 minutes walk from the beach. Kakaban was probably uplifted during theHoloceneera and seawater was trapped, forming a landlocked marine lake. The water is now a mixture of saltwater and fresh water from rain.

Barracuda Point

This is a steep wall, where the current brings largepelagicslikewhitetip sharks,leopard sharks,jack,tuna,snapperandbarracuda.Drift divingcan be done with the help of a grab line permanently secured 24 metres (79 ft) across a relatively flat area on the upcurrent side of the point. Currents can be fierce with down currents.

Blue Light Cave

Thecavestarts at a crack at 2 metres (6 ft 7 in) deep and descends through a narrowchimney.At about 21 metres (69 ft) the chimney opens into a large cavern that extends for about 120 metres (390 ft). The exit is a long vertical crack in the wall at 44 metres (144 ft). The name of the cave comes from the blue light of the sea which is seen from the cavern.