Category Archives: Shellfish

Washed Ashore: Soft-shelled Clam

Photo of Soft-shelled Clam

Soft-shelled Clams (Mya arenaria) are among the best known marine mollusks harvested from mud flats throughout New England. Also known as Long-necked or Steamer Clams, these shellfish are food for many species, including Atlantic Moon Snails, Green Crabs, various gulls and diving ducks, certain fish, Northern Raccoons, and, of course, humans.

The two halves of this bivalve's shell are similarly shaped, with the exception of the hinge area. The left valve has a spoon-like shelf, and the right valve has a corresponding groove to accommodate it.

To view the following images in full-size, click here.

Low Tide Life: Northern Moon Snail

Photo of Northern Moon Snail

Back in August, while wading in knee-deep water at a local beach, I noticed dozens if not hundreds of Northern Moon Snails (Euspira heros) slowly plowing through the sand. Having been familiar with their shells (empty, washed-ashore ones, that is) for years, I was thrilled to find some occupied dwellings.

The almost transparent bodies of Northern Moon Snails appear much too big for their shells, but as I experienced first hand, when picked up, individuals push water out of their shells and bodies and manage to squeeze into their nearly round homes without much trouble. A perfectly sized, flat operculum serves as the snug door a snail shuts to complete this marine magic trick.

These mollusks live in intertidal and, more commonly, subtidal waters along the New England coastline (and elsewhere) where they seek out meals in the form of Atlantic Surf Clams and other shellfish.

Bonus quiz: Find and identify the other mollusk in one of the following photos.

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Low Tide Life: Smooth Periwinkle

Photo of Smooth Periwinkle

Smooth Periwinkle (Littorina obtusata) is a small mollusk of the New England coastline who lives in association with Knotted Wrack, Bladder Wrack, and other types of marine algae. Smooth Periwinkle's nearly flat spire is distinctive among local periwinkles. Most of the individuals I've noticed have been yellow (another common name for this species is Northern Yellow Periwinkle), but shell color is variable, and may instead be red, brown, green, or multi-colored. To learn more about this mollusk, check out this species ID card offered by the Gulf of Maine Research Institute.

To view the following images in full-size, click here.

Low Tide Life: Atlantic Dogwinkle

Photo of Atlantic Dogwinkles

In addition to Common Periwinkles, I've eaten another local saltwater snail this year, the Atlantic Dogwinkle (Nucella lapillus). Also known as Dogwhelks, these native, pointy-shelled mollusks live in rocky, intertidal zones, alongside the non-native and often more numerous Common Periwinkles. Atlantic Dogwinkles come in a variety of colors (often white), have pointed spires (unlike the blunt spires of Common Periwinkles), and have a groove at the base of the shell opening.

Photo of Common Periwinkle vs. Atlantic Dogwinkle

Scouting out a low-tide Biddeford location, I was able to find areas with more Dogwinkles than Periwinkles, enough for me to feel comfortable harvesting a dozen to eat. After boiling them for a minute or two in saltwater, extracting them with a pin, and removing each operculum (the thin cover on their shell-opening), I enjoyed them as an oceany appetizer.

The top photo shows both snails -- Atlantic Dogwinkles (with white, pink, yellow and black shells) and Common Periwinkles (a light-tan one on left and a smaller, darker one on right). To view the following images in full-size, click here.

Low Tide Life: Blue Mussel

Photo of Blue Mussels

Blue Mussels (Mytilus edulis) live along the New England coast in intertidal and subtidal waters. They anchor themselves by attaching their byssus filaments to a substrate, and in turn sometimes serve as anchors for seaweed. These bivalves are preyed upon by fish, other shellfish, humans, and birds, including Herring Gulls and Common Eiders.

Two inedible mussel species also live in coastal New England waters. Ribbed Mussels (Geukensia demissa) prefer salt marshes and mud flats, and have radially ribbed shell surfaces, while Horse Mussels are typically larger than Blue Mussels, and have a double-bump at the narrow end of each shell.

Mainers can collect two bushels of Blue Mussels per day for personal consumption without a license, though, according to a 2015 article, these marine bivalves have become scarce in places where they were formerly abundant. Wild harvested or cultured Blue Mussels are available at fish markets and grocery stores near me for $2-3 per pound. (To view the following images in full-size, click here.)