Poisonous algae that glows in the dark detected in Åland Islands
In the Föglö area of the Åland Islands archipelago, a strange algal bloom has been detected that glows with a bluish light at night.
The algae begin to gleam in different shades of turquoise if the sea water is disturbed. The eerie glow is visible, for example, in the wake of a motorboat, a rowing boat, or even a swimmer.
According to the Finnish Environment Institute (SYKE) researcher Anke Kremp, this particular algae’s mass occurrence in the Finnish territorial waters was first detected in the Föglö area in 2003 and 2004.
This summer the phenomenon has been observed again in the same region.
The bioluminescence phenomenon, also known as “sea fire” is caused by single-cell microalgae, which start to radiate light when the surrounding water is stirred.
Microscopic examination has verified that the bioluminescence is caused by a dinoflagellate called Alexandrium ostenfeldii, which is relatively poorly researched.
The species is known to produce algae toxins. It is found around the globe as a background species among other algae.
The species has previously been detected in Polish and Swedish coastal waters, but recent investigations would seem to indicate that the Åland Islands find is genetically closer to a variety found in the Mediterranean.
This may mean that a new algae population has spread into the Baltic Sea.
Previously in HS International Edition:
Sea areas expected to have more abundant blue-green algae than last year (2.6.2009)
Marine Species Identification Portal
Alexandrium ostenfeldii (Harmful Marine Dinoflagellates)