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Clam Heaven
What Summer Brings to the Connecticut Coast
by Tessa S. Getchis
The boats are in the water, the
families are trading their hip boots
for Bermuda shorts, the permits
are flying off the shelf, and my
phone starts ringing. It’s that time
of year again - clamming season.
C
lam digging is a popular pastime along our coast. And
although clamming is open yearround, the high season occurs from
June to September when tourists
and locals vie for the best spots to
dig their dinner.
One of the questions I’m most
frequently asked this time of year
is, “Just what is a clam anyway?”
“Clam” is a common name for a
large group of shellfish called
bivalve mollusks. Like other
bivalves, clams have two symmetrical shells and soft bodies, but differ
in appearance from oysters, mussels
and scallops. Another way to distinguish among these bivalves is to
compare their habitat. Clams burrow, while oysters and mussels
attach to other objects (docks, pilings, boats, etc.). When provoked,
A recreational clam digger works a shellfishing area in Stonington, Connecticut.
scallops become mobile, appearing
to swim in a clapping motion
along the bottom.
What’s in a Name?
Three types of clams are
commonly eaten in Connecticut:
the soft-shell, Mya arenaria; the
razor clam, Ensis directus, and the
hard-shell clam, Mercenaria mercenaria. Soft-shell clams, also known
Ever ponder the difference among quahogs, cherrystones, hard clams,
littlenecks, and round clams? You’re not alone! To the newcomer these
terms are very confusing, but in fact, they represent the same animal,
Mercenaria mercenaria. Quahog, hard clam, and round clam are common names given to this species. In the marketplace, Mercenaria
mercenaria are separated into different size classes, with the smallest
being the most valuable: Littlenecks (width 1-2 inches; ~ 400 per
bushel), topnecks (width 2-3 inches; ~ 200 per bushel), cherrystones
(width 3-3.5 inches; ~ 150 per bushel), and finally chowders (width
3.5+ inches, ~100 per bushel)
as steamers, and razor clams are
popular for digging but less abundant than hard shell clams.
Connecticut’s hard-shell clam,
the northern quahog (pronounced
co-hog) is recognized as the most
important commercial shellfish
species on the East Coast of the
United States. The range of the
quahog includes the intertidal
(between low and high tide marks)
and subtidal waters (below the low
tide mark) along the Atlantic and
Gulf of Mexico, but quahogs are
harvested and cultured primarily
from Massachusetts to Florida.
The term “quahog” comes from
the Narragansett Indian words
meaning “closed” and “shell,” and
is used primarily in New England,
while from Connecticut through
Texas, “hard clam” is used to define
the same shellfish.
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Life as a Clam
Quahogs are found in soft or shell and
gravel-covered bottoms typical of Long
Island Sound. They have a grayish-colored
shell that is very thick, hence the name
“hard clam.” The two shells are hinged
together and held closed by two strong
adductor muscles. The inside margin of the
shell has a distinguishing purple hue. In
fact, it was this brilliant shell marking that
was carved, polished, drilled and turned
into wampum, the early bartering piece
used by Native Americans.
Hard clams are very slow growing. It
takes five to six years for a clam to reach a
harvestable size, and even longer in colder
climates. They are one of the longest-lived
shellfish, and it is not uncommon to find
clams that are 30 years old. The surface of
the shell is marked with concentric growth
rings. Clams have two joined siphons,
often called the “neck”, used for feeding and
respiration. Water is drawn into an inhalant
siphon, which contains a ring of tentacles,
and waste materials ejected out of the exhalant siphon. Quahogs feed on phytoplankton (microscopic plants), zooplankton (microscopic animals) and
decaying matter.
“It’s amazing how much water a clam can filter
through its body,” said Evan Ward, a shellfish physiologist at the University of Connecticut, “an adult can filter
8-10 gallons of water in a single day!” He adds, “this can
There are three types of clams commonly harvested by recreational diggers: the soft shell clam Mya
arenaria; (top), the razor clam,
Ensis directus (middle); and the
northern quahog, Mercenaria mercenaria (bottom).
Wondering what they
mean by “Happy as a
Clam?” Well, the actual
saying is “happy as a
clam in the mud at high
water.” Clams are easiest
to dig at low tide (when
the mud flats are
exposed) or in shallow
water. So if you were a
clam, you would certainly
be happy at high tide
when you were most likely
to escape predators of the
bird and human kind!
amount to as much as 5 to 10% of its dry body weight.”
Individual clams can be either male or female, and
in a few cases may change from male to female, a characteristic that scientists call protandric hermaphroditism.
They spawn from late spring to early fall depending on
temperature, usually mid-summer when the water reaches about 70 degrees Fahrenheit (21ºC) in our latitude.
Egg production peaks when the clam reaches two inches
in length (60mm), with an average female releasing
about two million floating eggs which are then fertilized
by male clams. The eggs develop into floating larvae and
by three weeks begin to settle and form a shell.
Adult clams have a strong muscular foot which they
use to dig, and once they find a proper place to live,
they stay put! Clams will only move up and down in
the sediment in an attempt to avoid predators such as
oyster drills, moon snails, whelks, sea stars, bottomdwelling fishes such as flounder and tautog, and various
crab species including the lady, blue, mud, rock, and
green crab.
Down on the Clam Farm
The inside margin of a hard clam shell shows a striking purple hue.
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Commercial harvesting of hard clams became
popular in Connecticut following a steady decline in
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Clams are suspension feeders. They
use their siphons to
feed on microscopic
organisms.
Inset: siphons
magnified, showing
fringe of tentacles.
oyster harvests during the
mid-19th century. The State’s
commercial industry began in the early 1960’s, with
modest harvests of a few thousand bushels. Today the
industry is comprised of approximately 50 companies.
According to David Carey, Director of the Department
of Agriculture’s Bureau of Aquaculture, “More than
420,000 bushels of hard clams were produced,
contributing greater than sixteen million dollars to the
State’s economy last year.” Connecticut’s production is
surpassed only by Florida and Virginia.
Hard clams are harvested or cultivated on leased or
franchised bottom in Long Island Sound. Mechanicallypowered dredges are the predominant type of gear used
to gather clams. The dredge is lowered from the side or
stern of the boat and dragged on the bottom in a large
elliptical pattern.
Shellfisherman Joe Gilbert explains how the clams
are collected: “Water is pumped through a hose into the
manifold where it is forced through a row of finger-like
jets. The water jets blow into the bottom of the Sound,
A hydraulic dredge uses water to soften the mud which the clams
live in. The shellfish are then scooped into the basket as it is
dragged along the bottom.
similar to putting a garden hose into soil, causing the
clams to be momentarily suspended in the water column. Blow-back jets force the clams into the cage of the
dredge.” When the basket is full, the deckhand hauls
the dredge on board for sorting. Many boats have a
mechanical grader, used to separate the clams into size
classes for market.
The clams are graded into bushel bags by size
including littlenecks (width 1-2 inches; ~400 per
bushel), topnecks (width 2-3 inches; ~200 per bushel),
cherrystones (width 3-3.5 inches; ~ 150 per bushel),
and finally chowders (width 3.5+ inches, ~100 per
bushel) Littlenecks are the most expensive grade of
clams, as they are sold primarily for the half-shell market. Larger clams are tough and meaty and commonly
used in chowders. Most of Connecticut’s clams are sold
to the New York market and are then shipped throughout the United States.
Many Connecticut shellfishermen cultivate clams,
relying on either natural seed production or hatchery
produced seed. Shellfishermen, as traditional farmers,
must prepare the bottom area and remove predators.
Clams may be graded and transplanted a number of
times to more productive growing areas. Under controlled culture conditions where shellfish are continually
monitored and protected from predators, growth and
survival rates can be greatly increased, and time to market size reduced to less than two years.
Run, Forrest, Run!
These ‘seed’ clams are only eight weeks old. They have a fully
formed shell and can bury into the bottom.
“Catching” clams is a tradition along Connecticut’s
coast, and the State supports a large recreational fishery.
Although the recreational harvest of hard clams is
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have openings or spacing between the teeth or prongs
of one inch or greater. You can either dig blindly
across a small area or look for a clam “show” –as clams
begin to burrow, they leave a small opening in the
sand where their siphons are located. Set your rake
about a foot ahead of the clam and pull the rake
towards you. When you hit the clam you’ll hear a
scratching noise. That’s your signal; back the rake up
and dig a little deeper in the location of the clam.
Clamming is a great summer activity for families
and quite a workout. Before digging, familiarize yourself with all the local regulations, obtain a permit and
call your local hotline* about shellfishing conditions
in your area before you dig. You can purchase a rake
and basket at your local bait shop or hardware store.
To measure your shellfish, be sure to carry a shellfish
ring, slot or gauge. And don’t forget your sun block
and bug spray. Nothing ruins a great day on the water
like being sunburned or eaten alive by bugs. Enjoy the
season!
Don’t risk it! Pay attention to closure signs posted by
your local shellfish commission.
insignificant compared to commercial harvest, the sale
of permits, rakes, bags, size gauges, etc. contributes to
the local economy. Each coastal town manages a recreational shellfishing program for their residents, based
largely on the popularity of harvesting hard clams.
Shellfishing regulations are established and enforced
to protect human health and also to preserve the living
marine resources and ecosystem within which they
exist. Each town within the State sets its own regulations including shellfishing species, size restrictions,
harvest limits, and closures. Harvesting is limited to
“Approved” or “Conditionally Approved-Open” areas.
Periodically these shellfishing areas may be closed due
to rainfall or pollution events. The status of these areas
can be obtained by calling the local shellfish information hotline or by checking with status signs, which
are posted at these areas for your convenience. These
classifications have been established by the State to
minimize health risks. Shellfishing during a closure
poses a serious health risk and it is illegal. Don’t risk it!
While some people use their feet to feel around
and pry clams from the bottom, the most popular way
to harvest clams is to use a clam rake. The rake must
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About the Author: Tessa Getchis is an Extension
Educator specializing in aquaculture with the
Connecticut Sea Grant College Program, based at the
University of Connecticut at Avery Point. She also took
the photos in this article.
*To learn more about and obtain shellfishing regulations
in Connecticut, and obtain hotline telephone numbers,
download a copy of “A Guide to Recreational
Shellfishing Along the Coast of Connecticut” from
http://www.seagrant.uconn.edu/shlfsh.pdf