Goby Lake

Although Jellyfish Lake is the most famous lake with jellyfish in Palau, it is not the only one. In more than 20 marine lakes (small saltwater lakes connected to the sea through limestone fissures) of Palau there is living jellyfish. Five of these lakes have been studied more – the mentioned Jellyfish Lake, Clear Lake, Uet era Ngermeuangel, Uet era Ongael and Goby Lake.

Testing ground for evolution

Each of the marine lakes of Palau has specific set of species occasionaly trapped in lakes by the receding sea 15 – 10 thousand years ago. Some lakes have steeper banks, some are elongated in east-west direction, some in south-north direction. Every such detail leads to different circumstances and consequently – different new species and subspecies of animals.

Some marine lakes of Palau are made even more exotic by the fact that they are meromictic – below the upper layer of marine water there is a layer of "dead", anoxic water separated by a layer of floating microorganisms, including a purple bacteria.

Such unusual monuments of nature serve as excellent "testing ground" for studies of evolution. Thus lately there several scientists have made interesting treatises about these lakes. Lucky them (scientists!) – making science in beautiful Palau…

Jellyfish of president Nakamura

Goby Lake is small (just 2.1 ha) meromictic marine lake with maximum length of some 260 meters and has formed rather recently (in geological terms). Lake is comparatively shallow – only the larger north-eastern part reaches 18 meters depth. Here, in north-eastern parte in 9 – 10 meters depth there is intense layer of purple-sulphur bacteria with anoxic water below.

Lake is rich with small fishes of several species (Acentrogobius janthinopterus, Exyrias puntang, Ophiocara porocephala, Parioglossus sp.) and is named after them.

The most renowned inhabitant of the lake though is an endemic subspecies of jellyfish Mastigias cf. papua nakamurai named after Palauan president Kuniwo Nakamura.

This jellyfish can become quite abundant in the small lake. It reaches 15 cm diameter, is somewhat asymmetrical, avoids the shadow.

Goby Lake is included in tourist routes although it is less popular than Jellyfish Lake.

References

1. Coral Reef Research Foundation, Marine Lakes Research Accessed 08.02.10.
2. Jellyfish swarms, tourists, and the Christ-child, Mike N. Dawson, Laura E. Martin, Lolita K. Penland. Hydrobiologia 451: 131-144, 2001. Accessed 08.02.10.
3. Five new subspecies of Mastigias (Scyphozoa: Rhizostomeae: Mastiigidae) from marine lakes, Palau, Micronesia, Michael N. Dawson. Journal of Marine Biological Association, U.K. 2005., 85., 679-694. Accessed 08.02.10.