Washed Ashore: Ocean Quahog

Photo of Ocean Quahog

In New England, a roundish black clam shell with a mahogany margin and a light-colored inner surface lacking a pallial sinus is that of an Ocean Quahog* (Arctica islandica).  The black coating -- known as a periostracum -- can flake off of washed ashore shells, resulting in countless unique designs. Ocean Quahogs are typically no more than 5" wide; the clam pictured here is about 3.5". Unlike some clams who can be dug by hand in mudflats, Ocean Quahogs live in deeper, sub-tidal waters. Harvesting is accomplished by dredging (source). Other names for this clam include Black Clam and Mahogany Clam.

Photo of Ocean Quahog inside

In researching these deep water clams, I also discovered a 2013 report which names a 507 year-old Ocean Quahog "the longest-lived non-colonial animal so far reported" (Science Direct).  I had no idea certain clams could live so long!

Photo of Ocean Quahog open

*Note: Ocean Quahogs are distinct from the more frequently eaten Quahogs (Mercenaria mercenaria) who live in shallower waters primarily south of Maine.

2 thoughts on “Washed Ashore: Ocean Quahog”

  1. Josh,
    Years ago, I used to make wholesale chowder stock in 80 gallon vats for a number of local restaurants. We used 5/8″ diced potatoes, Spanish onions, ground Mahogany Clams, and of course salt pork. After that, the individual establishments would add either milk, condensed milk, or cream to make a “New England” based chowder, tomato puree for a Red Chowder, or nothing but recovered clam juice for a more hearty (and truly New England) Yankee Chowder.

    I always favored the latter two because the flavor was better expressed with the more gamy Mahogany Clams, whereas Snow’s and Campbells used to use Surf Clams (Spisula solidissima) because the Midwestern palate didn’t care so much for the gamy flavor of the Mahogany (Artica islandica). By the time you cooked down the Mahogany Clams, you had a nice flavorful stock, made even more flavorful if one saves and filters the shuck water as in the Yankee Chowder. Cooking down the Surf Clams, however, tended to leave the chowder running between bland to sweet.

    As for Manhattan Chowder, that’s more like a can of Progresso Vegetable Soup with a single clam dragged through it. (Those New York people ……)

    I’m still exploring the rest of your site.

    (By the way, our Stuffies Recipe was to die for)

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