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Barnstable Clean Water Coalition is partnering with Popponesset Water Stewardship Alliance in order to monitor the spread of a new species of red algae called Dasysiphonia japonica (D. japonica).  Our team of interns monitor Barnstable beaches for inundations of algae, taking measurements, collecting samples, and recording weather and water quality data.  By knowing the time and locations of inundations we can start to track trends in its spread.

Around 2010 the Northwest Atlantic started seeing a this new species of red algae, D. japonica, washing up along its shores.  Thought to be brought here by aquaculture, D. japonica originally comes from Japan and the Korean peninsula and is rapidly spreading in the Atlantic.  D. japonica is very sensitive to excess nutrients like nitrogen and carbon and is outcompeting native algae and seagrasses, it also has a long growing season and fragments can clone themselves making the problem even worse.  When D. japonica blooms die off, they decompose and wash up onto local beaches creating a foul smell, as it decomposes it can also be harmful to juvenile fish and shellfish.  D. japonica has also been shown to alter community structure in a way that supports more animals at the bottom of the food chain such as amphipods, rather than larger animals like fish.

Popponesset Water Stewardship Alliance has a map of sightings in the area.

If you want to help monitor, or see an inundation on your local beach, you can click here to fill out a virtual datasheet to help us track this invader.

While D. japonica is probably here to stay, the only way to slow it’s proliferation is to stop putting excess nutrients into our coastal waters through our wastewater.

Click here for more information on Dasysiphonia Spotter Program from Popponesset Water Stewardship Alliance