Devastating Red Alga Discovered Creeping North to Maine

 
Shoals Marine Lab research student Hannah Hume examines a specimen of the invasive red algae Heterosiphonia japonica off Appledore Island, Maine, shgortly after it was first detected in 2011. Researchers at the lab have confirmed the algae has invaded the coastal waters off New Hampshire and Maine. Shoals Lab is operated jointly by Cornell University and the University of New Hampshire.

The shores of Appledore Island, Maine -- just six miles from the New Hampshire coast -- are being invaded by an aggressive red algae that can foul popular tourist beaches and damage vital local fisheries

The seaweed, Heterosiphonia japonica, is a native to Japan and has not been reported elsewhere in Maine to date. The brownish-red stringy plant was first spotted underwater on Appledore in 2011 by undergraduates in the Shoals Marine Lab Underwater Research class. By this summer most of the studied intertidal transects on the island -- permanent sites between the high- and low-tide lines -- contained Heterosiphonia.

The alga grows in the water along the shoreline, then detaches and creates vast, decaying piles in the intertidal zone along the shore. In some locations along the Atlantic coast, Heterosiphonia has covered beaches and threatened tourism with its foul odor. Biologists are also concerned that this seaweed may out-compete native plants, overwhelming local ecosystems and the commercial fisheries they support.

Researchers believe this species was transported to the Atlantic Coast on boat hulls or by shellfish aquaculture. It was first discovered in southern New England on Rhode Island's eastern seaboard in 2009.

So far, experts at the Lab -- which is jointly supported by Cornell University and the University of New Hampshire -- are cautious and say the impact of the red algae this far north has yet to be fully felt.