Phytoplankton causes 'tropical' blue water in Morro Bay

Phytoplankton is reportedly the source of a beautiful bright blue color in Morro Bay.

According to a report by KSBY , "it's the result of bioluminescence from marine microbes called phytoplankton that emit bluish light when agitated, in this case by the waves."

Photographer Luke Tyree captured photos of the bring blue bay.

He tells KTVU, "It looked almost identical to the naked eye, very bright and vibrant - we could see it from the parking lot 100 yards away." He said long exposures helped emphasize it in the photographs.

The photos were taken last week. It's unclear if the water is still bright blue.