Mission: Dasysiphonia

Kathy Ann Miller, Permitted Use

Research Question

How quickly is Dasysiphonia japonica (formerly Heterosiphonia) moving up the coast?

You’re Invited

Matt Bracken from Northeastern, Carol Thronber from University of Rhode Island, and Kathy Ann Miller and Robin Hadlock-Seeley from Cornell University’s Shoals Marine Lab want your help determining how quickly D. japonica is spreading up the New England coast. Be on the lookout for this species washing up on a beach or rocky shore near you.


Mission Steps

    1. Print the dasysiphonia ID card.

    2. Print the coastal species survey datasheet.

    3. Head to your favorite beach or rocky coastal spot. Look for feathery red algae. In some places dasysiphonia may form large mats washed up on shore. Your nose will help you! When these mats decay, they smell like rotten eggs.

    4. If you find red algae and you have access to a microscope, use it to capture photos of the cell structure of your sample. It is hard to tell dasysiphonia apart from other red algae species without a microscope. If you don't have a microscope, carefully store a sample in a sealed plastic bag and keep it safe in a cool place. We might ask you to send your sample in for a closer look.

    5. Post your “Found” or “Not Found” observation to your “My Vital Signs” page.

Red Riots, CC-BY

Why this mission matters

Dasysiphonia japonica (formerly Heterosiphonia) is native to Japan. It is believed to have made its way to the Atlantic Coast in the ballast water that is used to fill boat hulls. It was first discovered in Rhode Island in 2009 and most recently in Maine in 2011.

D. japonica has the potential to negatively impact local intertidal communities. It grows along the shoreline twice as fast as native algae, impacting eel grass and kelp beds that are really important nursery grounds for fish and crustacean species like lobsters. It also detaches during storms and creates large, decaying mats that deposit in the intertidal zone. As those mats rot they smell like rotten eggs, potentially impacting tourism at Maine beaches.

Red Riots, CC-BY

Want to know more?

Check out the species news page to see the latest news stories and learn about South Portland High students who were the first to report finding this species on shore in Maine.

You can also learn more at the New England Heterosiphonia Project.

Here are two scientific articles on H. japonica:

    Newton et al. 2013
    Savoie and Saunders 2013


This past week there's been lots of filamentous red algae washed up where I live in Rye, NH. I took samples of what I suspect are Heterosiphonia, along with the dominant local, I think, stuff. The alleged H. is very fine and when dry it drapes the cobbles above the tide as a pinkish red flat mat.
Here is a 40X photo of both. I think 100X would show cells more clearly.