The shellfish that
Rhode Islanders call a quahog possesses an impressive variety of names,
and even the word "quahog" (which comes from the Narragansett
Indian name "poquauhock") has an alternate spelling, "quahaug,"
and a number of pronunciations: KO-hog, KWO-hog, and KWA-hog. The quahog's
scientific name, Mercenaria mercenaria, is derived from a Latin
word meaning "wages" and was chosen because Indians used quahog
shells to make beads that were used as money (called wampum). In much
of the United States, quahogs are simply called "hard clams"
or "hard-shell clams."
live buried just below the surface in the bottom sand or mud, with
their two siphons sticking up into the water. Drawing
by Steve Silvia.
other names are based on a quahog's size. Little necks (or "necks")
are the smallest legal size, measuring 1 inch thick at the largest thickness;
chowders are the largest size; and cherrystones are in between.
In Rhode Island, quahogs grow to legal size in 3 to 4 years if conditions
are good. A quahog's age can be determined by counting the growth rings
on its shell. As quahogs get older, they grow more slowly, so the growth
rings get very close together and difficult to count accurately. Researchers
estimate that the largest quahogs (4 inches or more in length) are as
much as 40 years old.
Quahogs - like soft-shell clams, oysters, scallops, and mussels - are
classified as bivalve mollusks because they have hinged shells made up
of two halves, or "valves." Bivalves obtain their food by "filter
feeding." Water is taken in through a siphon and passed over the
gills, which are specially adapted to filter out food (microscopic algae
and other small organic particles). The filtered water is then expelled
via another siphon. A large clam can filter about a gallon of water in
Quahogs prefer salinities between 18 and 26 parts per thousand. This is
less salty than the open ocean (salinity about 35 parts per thousand),
so quahogs are often found in estuaries (like Narragansett Bay) where
the mixing of fresh and salt water provides ideal conditions.
Although quahogs can be found along the North American Atlantic coast
from Canada's Gulf of Saint Lawrence to Florida, they are particularly
abundant between Cape Cod and New Jersey. Farther north, most waters are
too cold for quahogs, restricting them to just a few relatively warm coves;
while to the south, quahogs have more predators, such as blue crabs.
Rhode Island, situated right in the middle of "quahog country,"
has supplied a quarter of the nation's total annual commercial quahog
catch. In 1987, the humble quahog was elevated to the status of Rhode
Island's official state shell.
Today, the quahog is by far the most economically important resource harvested
from Narragansett Bay. At the turn of the century, though, oysters dominated
commercial shellfishing in the bay. But the oyster population gradually
declined after the 1920s, and at the same time the quahog fishery expanded.
By the 1950s, two groups of quahoggers were competing for the resource
in the bay. The dredgers, who used boats to drag metal dredges across
the bottom, could harvest large numbers of clams much faster than could
the handrakers, who used their own muscle power to harvest quahogs with
bullrakes and tongs. The handrakers complained that the dredgers were
wiping out the quahog population, damaging clams, and putting the handrakers
out of work. Eventually the handrakers won out, and today dredging in
Narragansett Bay is severely restricted.
Significantly improved bullrakes, capable of harvesting quahogs from as
far down as 70 feet, appeared in the early 1970s. (Tongs and older bullrakes
could only be used in shallower waters.) Following this development, Rhode
Island quahog harvests increased steadily - from about 1 million pounds
in the early 1970s to about 3.5 million in 1980 - and have remained in
the vicinity of 3.5 to 4 million pounds per year ever since. In 1987,
the catch was 3,349,334 pounds of meats, with a value of $15.6 million
at the dock.
Pollution in Narragansett Bay affects the quahog industry because the
filter-feeding process concentrates not only food particles but also many
pollutants - including disease-causing bacteria and viruses, and toxic
compounds. Thus, even pollutants that are present only in low levels in
the water can accumulate to dangerous levels in filter feeders.
About 1/4 of Narragansett Bay's total area - including the Providence
River and Mount Hope Bay - is permanently closed to shellfishing because
of the danger of sewage contamination. In addition, a portion of the upper
bay is closed after rainfalls because antiquated "combined sewage"
systems in Providence and other towns allow inadequately treated sewage
to enter the bay during rainstorms.
your own quahogs
There is some
risk associated with any meat or seafood that is eaten raw. To reduce
the chance of contracting gastroenteritis, or possibly even more serious
diseases like typhoid or hepatitis, take care to collect quahogs only
from approved areas. Warning signs are posted in areas that are closed
due to pollution, but vandals sometimes remove the signs.
Rhode Island's basic statewide catch limit is 1/2 bushel of quahogs per
person per day. However, many places, classified as special shellfish
management areas, have lower catch limits and, in some cases, specific
opening and closing dates. These include all the coastal ponds, Greenwich
Bay, upper Narragansett Bay, and many other areas. All the special management
areas are listed in the leaflet Rhode Island Marine Fisheries Laws and
Regulations," available in bait shops or town halls.
Out-of-staters need a license, obtainable at town halls and bait shops,
to dig clams in Rhode Island.
For information about special management areas or closures due to pollution,
call DEM at 401-222-6800, or view shellfish closure maps on-line.
In some parts of New England, it is also important to watch for shellfishing
closures due to red tides. Shellfish taken from a red tide area can contain
a toxin that causes paralytic shellfish poisoning. The toxin is not destroyed
by cooking. However, no occurrences of red tide have been recorded in
Quahogs are found in the top 3 inches of sandy or sand-and-mud bottoms,
usually below the low-tide line. It's easier to dig for them at low tide.
Digging your own quahogs
requires little or no equipment. One popular method is "treading":
Simply probe the bottom with your foot until you feel a quahog, then reach
down and pull it up with your hand. Alternatively, you may use a hand
rake (available at hardware stores). A clam rake resembles a garden rake,
but the tines are longer and the handle is shorter. Drag the rake through
the bottom until you feel a scraping, then push the rake in deeper and
pull it toward you and upwards to harvest the quahogs. Be sure to wear
old shoes or sneakers to protect your feet.
Once you get the quahogs home, rinse them in cold water to remove sand
and discard any that have opened (they are either dead or dying). They
will keep up to a week in the refrigerator if they are unopened and laid
on their sides.
quahogs can be frustrating, especially for the novice. Clams "relax"
and become much easier to open if they are chilled, on ice or in the refrigerator,
for several hours. To open a clam, hold it in your left hand (if you are
right-handed) and use your right hand to work a special shucking knife
(available at the housewares departments of most stores, or at many fish
stores) into the space between the shells. As soon as the knife penetrates,
slide it along the inside of one shell to cut the two adductor muscles).
Open the clam and detach the meat by cutting the other side of the adductor
muscle. The quahog is now ready to be served on the half shell, used in
recipes, or frozen for later use. Quahogs make excellent chowder, clam
cakes, stuffed clams, and clam sauce for pasta. However, they are too
tough to make good steamed or fried clams.
Though purists would
object, quahogs that are not going to be eaten raw may be steamed or placed
in a microwave until they begin to open. These procedures make opening
the clams much easier but they also slightly toughen the meats.
FOR FURTHER READING:
Olsen, Stephen, Donald D. Robadue,
Jr and Virginia Lee. 1980. An
Interpretive Atlas of Narragansett Bay. Rhode Island Sea Grant,
1982. Secrets of Shellfishing. Hancock Plouse, Killingworth, CT
to Rhode Island Sea Grant Fact Sheets