On the beach last weekend, it wasn’t a purse snatcher that had me worried. It was a robber of another sort, a beach bandit that makes off with more than just money and jewels. It steals habitat, health and shellfish wealth.
Codium fragile is dastardly seaweed. It is ubiquitous on the beach and in our near shore waters. I know that you have seen this invasive green demon. It is one of the few green things this time of year and can be found rotting and stinking up seaside beaches here, there and everywhere.
Its physical characteristics are described by some of its many names. Green fleece or dead man’s fingers portray an accurate picture, since this algae has thick, dark to bright green rope-like strands that are not as fragile as its name might imply, and are attached to a holdfast which does just that: holds fast to any solid object. Herein lies one of the problems.
In the sea, there are only so many solid structures. Rocks come to mind, and codium does attach itself to them. Unfortunately, there are other creatures that present hard surfaces for this seaweedto grasp.
Shellfish are the losers in the war between weed and mollusk. Another of codium’s names, oyster thief, describes what happens when the codium attaches itself to an oyster, clam, slipper snail or any other live shellfish. The movable macro algae floats the shellfish away from its bed, drags it onshore, and can also suffocate it by interfering with its filtering ability.
Meadows of codium are formed when their fan-like array of appendages reach upward and outward and crowd out other algae, including the kelp that is necessary for the protection of juvenile fish. Codium can grow to two feet in height and spread out horizontally, pushing out everything in its path.
Although it’s now a problem, it did not always lead a life of crime. Codium was a solid citizen in its native homeland. It hails from Japan and the Pacific Ocean and found its way here sinisterly. Until 1957, no codium had ever been seen in these parts. Reported first in Long Island, N.Y., it travelled north until it came to Cape Cod in 1961 and is now seen all the way to Nova Scotia. Talk about a pervasive invasive! It has also been called Sputnik weed because its appearance coincided with the launch of the Russian satellite, and it seems pretty intent on winning the space race here in our shoreline habitats.
It arrived as a hitchhiker, either in ship’s ballast water or on fishing equipment, or perhaps from Pacific oysters dumped in eastern waters. It has easily spread by way of ocean currents and has very effective reproduction methods. Alas, it almost always beats the competition. There are very few options for successfully dealing with this invasive pest; I will share my favorite, though.
If you can’t beat it, eat it! Chef Jamie Oliver offers a tempting recipe for Soupy Rice with Codium, Goose Barnacles, and Lobster. Yum!
“Opportunity makes a thief,” FrancisBacon oncesaid. And this thief has opportunity in abundance in our rocky and shellfish-populated shores. Therefore, this insidious ball and chain will continue its felonious behavior — bullying the locals, suffocating the neighbors and harassing habitats indiscriminately. And the authorities are helpless. Since the police can’t handcuff the dead man’s fingers or put a stop to this habitat thief, we must find another way to arrest that seaweed!
Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.