SOMESVILLE — The recently greenish waters of Somes Sound have inspired many questions and an occasional joke amongst visitors and residents on Mount Desert Island.
And no, someone did not try to make a giant tequila sunrise. It’s also not dye either.
According to Kevin Lachapelle, a Maine Department of Marine Resources specialist based in Lamoine, the agency has been receiving reports of oddly colored water in the sound and has taken water samples. He believes there is a likely culprit for the odd-looking water.
Microbiologist Brianna King and Lachapelle, he said, “have taken a look under the microscope for phytoplankton and she thinks we may have seen evidence of a bloom of coccolithophores along with unsurprising amounts of some of our usual suspects (pseudonitzschia, scripsiella, dinophysis).”
This particular sort of phytoplankton is one-celled and exists together on the top layers of ocean water. They mass in large groups. Part of what makes them different is that they “surround themselves with a microscopic plating,” according to NASA. That plating is made from limestone.
The limestone scales are called coccoliths. They are hubcap-shaped. Each is just three one-thousandths of a millimeter in diameter.
According to an article on NASA’s “Earth Observatory,” “A bloom is essentially an abundance of phytoplankton — tiny, plant-like organisms that often float near the ocean surface. Phytoplankton fuel the ocean by feeding other plankton, fish, and ultimately bigger creatures. They are also important carbon cyclers and oxygen producers.”
These blooms are common offshore, but not as common in places like Somes Sound. They are also usually found in nutrient-poor, subpolar regions.
Lachapelle said, “A coccolithophore bloom would explain the color we are seeing, and some physical characteristics of Somes Sound might make it more susceptible to a bloom.”
“One of the main results of a coccolithophore bloom is that a lot of calcium is released when they die, which acts as a natural marine pH buffer,” Lachapelle said. “Brianna pointed out that the white cliffs of Dover are white because of calcium deposits from ancient coccolithophore blooms!”
These types of blooms are not known to have any negative effects on animal health, he said, but he and King will continue to monitor the situation. Dr. Jane Disney of MDI Biological Laboratory also has a student heading out to Somes Sound on Thursday to get samples.
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