North Iceland Lake’s “Poop Balls” About to Disappear Skip to content

North Iceland Lake’s “Poop Balls” About to Disappear

The rare phenomenon marimo (a.k.a. lake ball or moss ball), known as kúluskítur (literally: “poop ball”) in Icelandic is about to disappear from Lake Mývatn in northeast Iceland, according to research by Japanese plant physiologist Isamu Wakana.


Marimo. Photo by ESA.

Wakana is currently in Iceland for the sixth time to study the Mývatn marimo, which is believed to be one of only two locations where it exists in the world. The other is Lake Akan in Japan, reports. However, there are reports that it may exist elsewhere too.

Wakana dived in the lake on Thursday with employees of RAMY (the Mývatn Nature Research Center) in attendance to study the marimo’s state.

“We started suspecting two years ago that the marimo had decreased to such an extent that there are hardly any left,” said RAMY’s director Árni Einarsson. “When we first discovered it in 1978 there were […] tens of millions of lake balls in Mývatn, now there only appear to be a few hundred left.”

The remaining balls are scattered over a rather small area and their condition is not good. “They look rather limp, not firm and beautiful as they should be […] and hollow inside,” Árni said in description of their state.

Árni said it isn’t clear what is causing this development and it must be studied in more detail. The lake balls are known to be sensitive towards currents and light conditions, which depend on the amount of sediment in the lake.

A marimo is a rare growth form of filamentous green algae (Chlorophyta) where the algae grow into large green balls with a velvety appearance, as stated on Wikipedia.

Marimos are displayed at Sigurgeir’s Bird Museum on the banks of Lake Mývatn.

Click here to read more about the bird museum.


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