LIFE AT THE EDGE OF THE SEA
Everyone likes to be a beachcomber! And each passing tide exposes the
secrets of the sea to those interested enough to take a closer look.
Suppose that we examine this world which is revealed to us twice daily.
“WEEDS” OF THE SEA
The sea holds many strange plants that have taken on fantastic sizes and
shapes because of their underwater environment. In spite of their size,
these plants are usually among the most primitive—a simple sheet of
cells. Such plants are called _algae_ and are subdivided according to
their colors.
_The Brown Algae_
[Illustration: Common Rockweed]
Common Rockweed
(_Fucus_, several species)
Brown, flattened body
Central midrib
Stem has air bladders
The bladders are filled with air, and children like to squeeze them to
hear their pop. These bladders cause the plant to float upright, thus
keeping all its sides in contact with water.
[Illustration: Nodose Rockweed]
Nodose Rockweed
(_Ascophyllum nodosum_)
Thin, round stem
No central midrib
When dried by the sun, this plant makes an interesting and lasting
souvenir, for it turns a lustrous black.
[Illustration: Common Kelp]
Common Kelp
(_Laminaria agardhii_)
Broad, flat blade
Several feet in length
The kelps of the Pacific grow several hundred feet in length, making
them the largest of the algae and among the very largest plants.
[Illustration: Fingered Kelp]
Fingered Kelp
(_Laminaria digitata_)
Many blades, extending like fingers on a hand
All kelps have a rootlike structure called a “holdfast” to serve as an
anchor. Often tiny sea creatures dwell in among the holdfast. Why not
take a look?
[Illustration: Perforated Kelp]
Perforated Kelp
(_Agarum cribrosum_)
Central midrib
Broad blade punctured with hundreds of holes
In Asia this kelp is farmed for food called agar. An extract of the
plant, agar-agar, is used in the laboratory as a culture medium for
bacteria and other disease-producing organisms.
_The Green Algae_
[Illustration: Sea Lettuce]
Sea Lettuce
(_Ulva species_)
A sheet of green
This is a very simple seaweed that reproduces itself by fragmentation,
each fragment growing into a new plant. Two common kinds are found at
Crane’s Beach:
_Ulva lactuca_, which is the broad green “leaf”; _Ulva lanceolata_,
which is in thinner, more ribbon-like strips.
_The Red Algae_
[Illustration: Irish Moss]
Irish Moss
(_Chondrus crispus_)
Flattened, branching fronds
Purple in life, white when sun-bleached
Here is a very common tidal plant that has commercial value. It is
called “Dulse” on the Boston markets, and a very delicious pudding is
prepared from it (seamoss farine). Why not take some home and try it?
[Illustration: Polysiphonia]
Polysiphonia
(_Polysiphonia_, several species)
Pink or red color
Branching, lace-like appearance
Sometimes called “Mermaid’s Hair,” these tiny plants are very common on
the beach. There are many kinds of Polysiphonias, but a microscopic
study is usually necessary to tell them apart.
[Illustration: Coralline Algae]
Coralline Algae
(_Coralline_, several species)
White or pink limy covering
Appear jointed
These plants have the amazing ability of concentrating lime from the sea
water and depositing it on their fronds, thus acquiring a stony,
coral-like appearance.
ANIMALS OF THE SEA
[Illustration: Dolphin]
Animals, in a kaleidoscope of unbelievable sizes, shapes, and colors,
abound here at the margin of the sea. Specializations range from the
single-celled body of the zooplankton to the multicellular body of the
Seals and the occasional Porpoise.
_The Sponges_
[Illustration: Finger Sponge]
Finger Sponge
(_Chalina oculata_)
Brown or tan color
In colonies of fingerlike projections
The most common sponge on Crane’s Beach is the Finger Sponge. Even a
small piece may be identified by the holes on its surface, through which
the animal filtered water. The strange appearance of this sponge has
given it the repulsive name of “Dead Men’s Fingers.”
[Illustration: Crumb-of-Bread Sponge]
Crumb-of-Bread Sponge
(_Halichondria panicea_)
Pale green in life
Light tan or white when dried on beach
Crumbles easily
Only the most searching eye will discover this sponge, because it so
closely resembles a dull uninteresting rock or pile of bread crumbs.
When it has been freshly broken, it has a vile odor—a good clue to
identification.
_The Jelly-like Animals_
[Illustration: White Jellyfish]
White Jellyfish
(_Aurelia aurita_)
Flattened body
Under 10″ in diameter
The tentacles dangling down from the underside of this jellyfish are
covered with tiny stinging cells, which in this species do not penetrate
human skin.
[Illustration: Pink or Red Jellyfish]
Pink or Red Jellyfish
(_Cyanea capillata_)
More than 10″ in diameter
Reddish center, yellowish sides
This jellyfish occasionally grows up to eight feet in diameter, with
tentacles a hundred or more feet long. The stinging cells can painfully
wound a swimmer, but you may examine a small jellyfish safely by placing
your hand on the smooth dorsal surface and turning it over.
[Illustration: Sea Anemone]
Sea Anemone
(_Metridium dianthus_)
Cylindrical, soft body
Tentacles at top give flower-like appearance
Generally very colorful
The “petals” of the Sea Anemone’s flower-like head are actually
tentacles covered with stinging cells and used to stun its food.
Generally found in the water at tide level, the Sea Anemone moves by
walking on its single, base-like foot.
_The Worms_
[Illustration: Clam Worm]
Clam Worm
(_Nereis virens_)
Jointed
One pair of paddle-like feet per segment
Two “tails”
Pinchers on the head (watch out!)
This is the best-known worm on the beach because of its desirability as
fish bait. During the day it lives in its burrow in the sand, wandering
forth at night and swimming about in the water, where it becomes easy
prey for gulls and fishes. The skin is brilliantly iridescent in the
sunlight.
_The Crustaceans_
[Illustration: Common Barnacle]
Common Barnacle
(_Balanus balanolides_)
Common on rocks and shellfish
White, volcano-shaped shell
Two “barn doors” at top
This animal goes through life standing on its head and kicking food into
its mouth with its feet! When it is submerged in sea water you can see
its shell doors open and its feather-like feet sweep the water for
microscopic food organisms. The limy shell first suggests a relationship
with the clam, but body structure shows it to be a closer relative of
the crab.
[Illustration: Shrimps]
Shrimps
(_Crago septemspinosus_, the Sand Shrimp, and _Palaemonetes vulgaris_,
the Prawn)
Hard, transparent shell
Long antennae
Paddle-like tail
These tiny tide-pool creatures look for all the world like the larger
edible shrimp served in local restaurants. Actually, these miniature
two-inch-long shrimps are edible also, and quite enjoyable if you have
the time and patience to collect enough for a meal.
[Illustration: American Lobster]
American Lobster
(_Homarus americanus_)
Bits and pieces of Lobster are frequently found on the beach, but seldom
the entire animal. The Lobster inhabits deeper water and finds its way
to shore only after losing a battle with one of its enemies. A favorable
dining size is one or two pounds; however, Lobsters do attain weights up
to forty pounds.
[Illustration: True Crabs]
True Crabs
(Cancridae and Portunidae)
Football-shaped in cross section
Two large claws
Eyes mounted on stalks
The three very common True Crabs of Crane’s Beach may be found in one
search of the tidal pools. They are:
Rock Crab (_Cancer irroratus_): A brick-red shell, somewhat
granulated, with a black and yellowish undersurface.
Jonah Crab (_Cancer borealis_): Similar in color to the above, but its
shell has a more sculptured surface.
Green Crab (_Carcinides maenas_): A greenish-colored shell. The last
pair of legs end in sharp points, rather than being flattened like
paddles.
[Illustration: Horseshoe Crab]
Horseshoe Crab
(_Limulus polyphemus_)
Shell with horseshoe-shaped outline
Long, sharply pointed tail
Two immovable compound eyes
The Horseshoe is not a Crab at all, but is more closely related to the
spiders, mites, and scorpions. In spite of its relations, the Horseshoe
is a harmless creature whose only protection is its hard shell.
Therefore it may be examined freely—a strange “living fossil” that has
survived 400,000,000 years of evolution with very little change.
_The Mollusks_
[Illustration: Oyster]
Oyster
(_Ostrea virginica_)
Mottled, unattractive shell
Gray splotches on inside surface
Even without pearls, our Oyster is worth many thousands of dollars a
year to shellfish dealers because of its delicious flesh. Its tropical
relatives are the pearl producers.
[Illustration: Mussels]
Mussels
(_Mytilidae_)
Blue-colored shells
Shells covered with black, horny skin
Living mussels are always found attached to rocks or pieces of wood by
tiny threads of their own making. Two common mussels are:
Edible Mussel (_Mytilus edulis_): Smooth, velvety-blue shell
identifies it. The animal within is edible and quite delicious. It is
commonly utilized as food in Europe but less so here, where we have,
and seem to prefer, the Oyster.
Ribbed Mussel (_Modiolus demissus plicatulus_): Similar to the above
but with many distinct ribs radiating on the surface. The Ribbed
Mussel is not considered edible. While not poisonous, it is most
unpalatable.
[Illustration: Hardshell Clam]
Hardshell Clam
(_Venus mercenaria_)
Thick, round shell
Purple blotches on inside surface
Also called “Quahog,” “Little Neck,” “Round Clam,” or “Cherrystone,” the
Hardshell Clam is another highly prized seafood.
[Illustration: Edible Clam]
Edible Clam
(_Mya arenaria_)
Fragile shell with egg-shaped outline
Wing extending out from inside top of left half of shell
These clams are found just a foot or so under the sand, and their empty
shells are common on the beaches. This is the Softshell Clam, which we
enjoy steamed, baked, or fried, as well as in New England’s famous
clambakes and clam chowders.
[Illustration: Surf Clam]
Surf Clam
(_Spisula solidissima_)
Very large shell
Spoon-shaped trough at inside top of shell
This is the largest clam on the Atlantic seaboard, growing up to about
seven inches in length. It is edible, and just one or two make a large
chowder. The shell makes a fine ashtray and an unusual and useful
souvenir.
[Illustration: Razor Clam]
Razor Clam
(_Ensis directus_)
Elongated brown shell
The Razor has a very large foot, with which it can often dig faster than
the hand trying to discover it. Although delicious, the Razor Clam is
seldom seen on the markets because it is so difficult to capture.
[Illustration: Snails]
Snails
(Littorinidae, Thiasidae, and Naticidae)
Clams in a coiled shell
Several species are found at Crane’s Beach:
Periwinkles (_Littorina_): These have a wrinkled shell about the size
of a thumbnail. Because they are able to withstand long periods
without water, Periwinkles are often found high on a beach.
Rock Purple (_Thais lapillus_): Has a rough, white shell coming to a
point at the top. This snail secretes a purplish dye that was used by
the American Indians and the ancient Phoenicians to produce their
“royal purple” dyes.
Moon Snail (_Polinices heros_): Large white shell with almost round
shape. The Moon Snail lays its eggs in a sand “collar,” which is
frequently discovered on the beach in its dry state.
[Illustration: Slipper Shell]
Slipper Shell
(_Crepidula fornicata_)
Shell is boat-shaped
Tiny “seat” inside shell
This animal protects its bare underside by attaching itself to a handy
rock with its suction-cup foot. Often there are enough of them to give
the rock a warted appearance.
_The Spiny-skinned Animals_ (_Echinoderms_)
[Illustration: Starfishes]
Starfishes
(_Asterias vulgaris_, and others)
Five-armed body
The Starfish seems to like Oysters as well as we do, and it opens them
by sheer strength. Oystermen used to tear Starfish apart to destroy
them, until they discovered that each arm has the ability to regenerate
and become a whole starfish!
[Illustration: Sea Urchin]
Sea Urchin
(_Strongylocentrotus droehbachiensis_)
Round body
Covered with spines
Here is a creature with a scientific name much too long for its size.
Indeed, the name is said to be the longest in animal nomenclature. The
Sea Urchin is a living fossil with four times as many extinct cousins as
living ones.
[Illustration: Sand Dollar]
Sand Dollar
(_Echinarachnius parma_)
Silver-dollar size and shape
Raised, star-shaped pattern on back
This is an animal of deeper water and so the bather seldom sees a live,
heavily spined specimen. We find the dry, spineless shells on the beach.
Wrap them carefully if you wish to take them home, because they are most
fragile.
_The Fishes_
The waters off Crane’s Beach abound with many dramatic fishes such as
Cod, Mackerel, Flounder, and Sand Sharks; but we are concerned only with
the common tidal fishes that are regularly washed onto the shore.
[Illustration: Pipefish]
Pipefish
(_Syngnathus fuscus_)
Lead-pencil size and shape
Hard, bony plates cover body
One look at a Pipefish will convince you that it must be related to the
Seahorse. It spawns late in the spring, the female laying her eggs in
the pouch on the stomach of the male. The male carries these eggs
kangaroo-fashion, until they hatch during the summer.
[Illustration: Silverside]
Silverside
(_Menidia menidia_)
Silver stripe running down a light side
These fish are also an important food item for the Gulls and Terns.
Silversides run in schools of a hundred or more, which can be located by
the flocks of birds gathered round overhead.
[Illustration: Skates]
Skates
(_Raja_, several species)
Strange bat shape
Long ratlike tail
These are harmless fish resembling the dangerous Rays of the tropics,
except for their habits. The egg cases of the Skate are rectangular,
black, horny envelopes. They are commonly found on the beach, where they
are called “mermaids’ purses.” If you find a fresh one and open it, you
may discover a miniature Skate inside.
[Illustration: Killifish]
Killifish
(_Fundulus heteroclitus_)
Stout, olive-green fish
Rounded tail
The “Chub,” well known to fishermen, can live for a day covered only
with a layer of damp seaweed. It does us a real service by feeding on
the mosquito larvae in brackish water.
[Illustration: Sticklebacks]
Sticklebacks
(_Gasterosteus_ and _Apeltes_ species)
Spines on the back
Very narrow base to tail
During the early summer months, the Stickleback builds a barrel-shaped
nest, held together with gelatinous threads. After the eggs have been
deposited, the male guards the nest with amazing vigor, considering his
size.
[Illustration: Sand Lance]
Sand Lance
(_Ammodytes americanus_)
Knife-shaped body
Long dorsal fin (fin on back)
Protruding lower jaw
Thriving abundantly off the beach, the Sand Lance is an important item
in the diet of shore birds.
FOR MORE INFORMED BEACHCOMBING
Thus begins our day of beachcombing. Every animal and plant of the sea
has a tale to tell and some of the most exciting of all are found in
this ribbon-like strip of water in the tidal wash.
For your further investigation, here is a list of reference books:
Charles M. Breder, Jr., _Field Book of Marine Fishes of the Atlantic
Coast_. Rev. ed. New York: Putnam’s, 1948. $5.00
Ralph M. Buchsbaum, _Animals without Backbones_. Rev. ed. Chicago:
University of Chicago Press, 1948. $8.00, text ed. $6.00
Rachel L. Carson, _The Edge of the Sea_. Boston: Houghton Mifflin,
1955. $3.95
Roy Waldo Miner, _Field Book of Seashore Life_. New York: Putnam’s,
1950. $7.00
Percy A. Morris, _A Field Guide to the Shells of Our Atlantic and Gulf
Coasts_. Rev. ed. Boston: Houghton Mifflin, 1951. $3.95
Herbert S. Zim and Lester Ingle, _Seashores: A Guide to Animals and
Plants along the Beaches_. New York: Golden Press, 1955. Cloth
$2.50, paper $1.00