CLAMS
A large number of bivalved mollusks, which are
sought as food or bait. Clams are an important item in
the restaurant trade and are collected in great quantities
by people along both coasts of the United States. Nearly
all clams are delicious to eat, although the meats of some
species are bitter. Depending on the environment, clams
can be toxic or deadly to humans, depending on either
(1) the occurrence of noxious plankton blooms (see Red
Tide) or (2) the presence of pollution (which see) from
untreated sewage. It is advisable to check with local
health authorities in all areas where these bivalves are
taken as food. Some forms of hepatitis may originate
from eating raw clams. Commercial stocks must pass
rigid inspection.
In the United States one of the best known clams is the
softshell clam Mya arenaria. Along the Atlantic coast it
occurs from the Arctic Ocean to Cape Hatteras, and it
has been introduced into western Florida where it has
done exceptionally well. It has also been introduced into
Europe, although it is not especially sought there as food.
It also occurs in central California. Found on mud flats
and under stones, generally in the intertidal zone, it is
avidly sought by gourmets and beachcombers. The hardshell
clam, Mercenaria mercenaria or quahog (pronounced
co hog) is equally delicious and is avidly sought, being
eaten more often cooked and in chowder than the softshell,
which is considered a delicacy raw as well as cooked.
Usually found from 1-6 fathoms deep, hardshells can be
obtained commercially by clam rakes operated by hand or
using hydraulic dredge boats, which utilize high-pressure
jets of water that unearth the clams from their burrows.
These are then picked up with large rakes or dredged;
such operations usually being carried out from mediumsized
boats. A related form, the surf or skimmer clam,
Polynyma solidissima, is also highly esteemed for use in
chowder. It is found in water deeper than the soft or
hardshell cams. Along the Pacific coast of the United
States, the geoduck (pronounced gooey-duck), Panomya
generosa has a large, delicious siphon, which may be up
to six or seven times as long, when protruded, as the
shell, which grows to about 7 inches. Other delicious
clams are the bean clam (Donax spp.), a small, colorful
clam found in the intertidal zone, and which is delicious
in soup; and the cockles, which are especially prized in
Europe, both as fresh food and in stews and chowders.
One large clam, the granddaddy clam, Tridacna gigas,
occurs throughout Oceania and is especially sought as a
souvenir. Its shell is white with pink, orange, or blue
tints, and is delicately sculptured. Large individuals
reach 500 pounds. Although it is alleged that native divers
have been trapped in the powerful jaws, there is no record
to authenticate this report.
FRESHWATER CLAMS
Several species of freshwater bivalves are called
"clams," but these are really mussels which belong to the
family Unionidae. They are important in the pearl button industry and for making essence of pearl.
-D.DS. from McClane's New Standard Fishing Encyclopedia